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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Restoration of a starter

Decided to start a new thread in this topic as it is distinct from Michael's Hi-torque starter one.
I am checking and hoping to restore my starter to good health. It runs on no load, but just spins up with no realkick as I would expect. I think it should do better. I have dismantled it and cleaned most of the residue of copper impregnated grease from inside. The brushes are still intact, but fairly worn so a set are on order. In the meantime I have been checking with my meter. This is what I have:

1. I get a fairly low resistance between the end of the power feed terminal and the casing. I don't think this can be right?
2. I levered the brushes off the commutator and removed the end plate. Now the meter shows no continuity between the exposed power feed pin and the casing, which I think is better.
3. The power terminal is one end of a thick 3mm X 5mm flattened wire that winds its way around 4 coils in series, ending at a connection, crimped onto the braided copper tails for 2 of the brushes.
4. Meter shows* 00.4 between brushes and the power terminal. So the 4 coils in series have negligable resistance.I presume this is right, and that they need to be isolated from the casing Am I right?
(*presumably this means 0.4 ohms? Meter is on lowest setting marked 200 ?? Am I reading it right?)

Inside the casing, and around these field coils is all a bit of a mess. There are bits of very thin tape of some sort flapping away in numerous places and clearly not doing anything useful. The smart thing would be to remove all of these parts from the casing, clean down and if necessary rebind wires with insulation tape, if only to keep everything in place. But none of the 4 large cross-head screw is moving, despite attacking with a heavy hammer and impact driver.
Despite the mess in there, I get a good resistance reading between the coils and the casing, so should I leave all that alone?
The sheathing on the braided brush tails is damaged and that may be where it was shorting when assembled. I can replace that when I renew them.
The other suspect place is where there is a very thin and worn insulated collar on the connecting bolt as it passes through the end plate. I think I can improve on that arrangement, drilling the hole oversized and fitting a new insulating sleeve.

This is a learning process whilst I wait for the new brushes. I could just buy a new starter but for now I want to see if this is fixable as that is the best way to learn!
GuyW

Hi Guy,

I’ve not stripped down a starter myself, but below is a link to the Lucas fault finding and service manual which may be of some help

https://www.gomog.com/allmorgan/LucasFault.pdf

218 & 246 of the University Motors youtube videos are about the starter motor.


Simon
S Holt

Hi Guy,

I’ve not stripped down a starter myself, but below is a link to the Lucas fault finding and service manual which may be of some help

https://www.gomog.com/allmorgan/LucasFault.pdf

Simon
S Holt

What about the JT vids?

246 MG T type / MGA / midget M35G Starter Motor Repair - https://www.youtube.com/watch?v=kmh2qZgfv1Q

and the famous safety video! -
218 MG M35G Starter MGTD MGTD mgtf MGA MG Midget 1950-1979 - https://www.youtube.com/watch?v=R6CR_8efA88
Nigel Atkins

Thanks Simon (X2!) I've downloaded that pdf. Could be useful though my little digital meter won't be up to doing those voltage drop tests.

Thanks Nigel. Not come across those videos, but will take a look
GuyW

If you've not seen them you'll love 218! :)
Nigel Atkins

Yep, I edited the post to include mention of the videos then ended up sending the original as well!
S Holt

Thanks Nigel. 218 is a pretty dire way of removing a Bendix! I thought this JT bloke was supposed to be some sort of expert! That is not how I do it!

The other video looks better to me. I will look at it properly later but fast forwarding through the first 2 or 3 minutes of waffle and it looks like it might become useful after that.
GuyW

Your low resistance measurement is correct. The motor is "series wound" meaning the field is in series with the armature - this produces a high (necessary) starting torque. Also, to produce the required starting torque the motor draws a very large current, 100A or more, so is bound to be low resistance (R=V/I) as measured with a meter, both for field and armature.

Removing the brushes would give zero continuity as you found because you've broken the crcuit. The 0.4 ohms is ok, it's probably lower actually as digital meters don't seem very accurate below a few ohms.
Bill Bretherton

Simon, take no notice of me pulling your leg I often cock up posts even with the 15 mins edit.
Nigel Atkins

Guy,
JT also uses a screwdriver across a live starter solenoid!



Sorry, just couldn't resist. :D




Nigel Atkins

Thanks Bill.
So if I consider the electricity as flowing, it comes in from the solenoid to the brass terminal on the endplate, which should be isolated from the body of the motor.

This terminal is a direct connection to one end of the first of the 4 coils. The flow then goes around each of the four coils in turn and exits at a crimped connection to two of the 4 brushes.

Those two brushes then feed into opposite sides of the commutator so that at any one instance there are two of the armature coils energised (or maybe they are slightly out of step to even out the flow?)
Having whizzed around the armature windings the flow exits via the two other brushes, which presumably then both need to be connected to the body of the starter to complete the circuit to earth (Neg)

A short length of woven sheathing on one of the two tails from the field coils is damaged and I think has been shorting onto one of the long screws that hold the whole thing together. If this is the case, then presumably only half of the armature windings are getting power, which would explain its less than enthusiastic operation.
GuyW

<<JT also uses a screwdriver across a live starter solenoid!>>
Nothing wrong with that Nigel.
Doesn't make his efforts with the Bendix any safer though!

I know JT is quite popular and he does cover a good range of stuff. Its just that I find his videos pedantically slow and dislike his style in that silly Dutch cap of his!
GuyW

Your reasoning makes sense Guy. It would be good if you could repair it!
Bill Bretherton

Update on my starter repair.
At the moment I am grinding to a halt with this little project. Brushes arrived, and I successfuly welded the two earthing brushes that connect to the motor end plate terminals. But I am having difficulty with the other two that both connect to the free wire end of the series of 4 field coils. I cannot get the solder to take.

I am using an old 140Watt ex GPO electric soldering iron with a large copper tip. It heats to the point that the solder fully melts but it is just turning into globules and running off. The coil is made of a grey flat cable which doesn't want to take the solder. I am advised by someone who knows about this sort of thing, that it is possibly aluminium or an alloy of aluminium. So the question is, what to try next?

Plan Z, BTW is to buy a replacement starter. Plan Y is to take it to a local auto-electrician and plead to him to just attach the brush tails. But for now I would prefer to learn how to do this repair myself.
GuyW

Could you scrape the end of the coils to ascertain what the material is? Then, if copper, sounds like more heat is needed. I'm guessing the thick wire is taking the heat. In a sense, you've nothing to lose trying more heat as the motor doesn't work properly anyway. Could you use the iron that you heat up with a flame?
Bill Bretherton

The metal isn't copper Bill. Its a dull, pale grey. But bright if scratched. Pretty sure it's aluminium. I am getting it pretty hot. Holding my large electric iron against the underside of the "wire" it conducts heat through to the upper side where my solder melts and dances around as a ball, but just runs off and won't stick. It's clean and flux is not helping.

There is a product called Durafix which is a low temperature aluminium welding product which might work.
https://www.durafixonline.com/gb/7-aluminium-welding-rods

One slight difficulty is working within the body of the starter, so access is a bit restricted, and working in there with a flame is awkward.

GuyW

You'll likely be better with suitable wire and flux. CUP alloys do a couple of possibilities Alusol wire in this list https://www.cupalloys.co.uk/soft-solders/ and flux in this list Stay-clean aluminium flux https://www.cupalloys.co.uk/soft-solder-fluxes/ . They're quite helpful and should be able to advise but whether they're still open or not this close to Christmas I couldn't say. How were the wires originally fixed to the field coils?
David Billington

David, they appeared to be soldered on originally. At least when I removed the old braided copper wires I did this by melting the "solder" (if that's what it was) with my smaller 50W electric iron.
In retrospect, I should have clipped the wires, leaving enough of a stub of the copper braiding to solder the new tails to.

One issue is I think, that even with my 150W iron, the heat is dissipated down the fat coil wire very quickly.

I will take a look at that CUP alloy site.
GuyW

If you undid the original wires with a 50W iron then it should just be solder, but what sort? Aluminium melts at about 640C. Is any of that original solder still in place that you might be able to fix to, maybe trying a pre-tinned copper lead against it. What flux are you using? I wonder if Lucas added some form of plating to the aluminium, if it is, to allow for easy use of a soft solder on an otherwise difficult to solder material.
David Billington

I'm surprised the wire is aluminium. Perhaps a later starter?
Bill Bretherton

Bill, starter is dated 1969 (Lucas date code) It's on my Sprite, build date may 5th, 1971

David, thinking that it would be important to be soldering to a clean surface, I did try to clean the wire fairly thoroughly so have probably removed any plating or remnant solder.

Somebody must surely have replaced brushes on these 25079 starters! Or does nobody fix stuff these days.
GuyW

Guy
Can you try tinning the aluminium first,
Flux and heat and try scratching the surface below the flux before adding a tin: lead solder.
There are special fluxes for Ali, I find some of the modern plumbing fluxes are not as good for general work as the old Fry Fluxite types.

Can you try reattaching the old wires if they have the old solder in them ?

R.
richard b

Richard,

Never particularly liked the Fry's Baker's fluid flux as it tended to run off in my experience but is basically what I used in a metal smithing class for soldering modern pewter (Britannia metal) it being basically a saturated solution of zinc chloride in water which the teacher made up. I do use an acid paste flux which is grease like for some soft soldering and stays in place better. I find a better flux for pewter and it seems to work just as well for other non ferrous metals such as brass, copper, and similar is 285g glycerine + 5ml 36% HCl (hydrochloric acid), both readily available, or were a few years ago when I bought the HCl off ebay, glycerine available in Boots and elsewhere, those measures being for making up about 250ml quantities, activeness can be adjusted by altering the HCl quantity. Metering out the HCL was easy with the burettes I bought for head chamber volume measuring.
David Billington

It hadn't really occurred to me that there were different fluxes, I just thought they were different brands. Almost all of my soldering experience has been electrical and plumbing, plus some model making with copper, brass and steel. I do also have a flux paste I use for lead loading which I could try. I may get back to this job for another attempt later today.
GuyW

Hi Guy,

I had an issue with a starter earlier this year and ended up in the same situation as you - trying to solder to the aluminium.

I failed and bought another starter!

Sorry - not helpful, but I sympathise with how difficult it is.

Good luck.

Malc.
Malcolm

Ahh, well Malcolm, if a proper engineer failed, that doesn't bode well for my attempts!
GuyW

I've never soldered aluminium wire as I know it's very difficult - again, not much help Guy.
Bill Bretherton

Keep at it Guy and let me know how it's done! It's not my area of expertise and I didn't try all that hard.

I tried 50W iron, a blow torch, plumbers flux and solid solder and flux cored (electronics type 60/40 blend) solder and combinations thereof. None of it stuck!

Malc.
Malcolm

Just an additional ponderation... When welding aluminium, you need to remove the oxide layer immediately before you weld. Aluminium, being so reactive, forms an oxide layer in ten minutes or less.

I would imagine it is the same soldering. You need to clean it up to bright, shiny alu' with some new, clean wet and dry paper would probably do. Then try soldering, and then you probably only get one shot before you have to clean it up again.
Malcolm

This might help.

https://superiorflux.com/techniques-for-soldering-aluminum/
anamnesis

Is this the item in question?

Interestingly, John Twist refers in the video, to the field being alluminium.

But, in the text from the Lucas starter motor manual, it says copper, due to the current being between 200 and 300 amps.





anamnesis

Yes, that's it. Original Lucas 1969. Very definitely not copper strip for the windings, unless someone has invented copper that is aluminium coloured even when scratched!
GuyW

Here's my take, which may be wrong. The field tails are tinned copper.

The field is still in the heavy metal casing (you weren't able to remove the field), which is a huge heat sink.

Although the field tail, is hot enough from the tip of the iron, to melt the solder (lower melting point), the tinned field tail, is still too 'cold' to accept the solder, so it rolls off. (This also happens when you try to tin the tip of an iron, when it has not reached a hot enough temperature from cold).

Or, it is ally, in which case all the above is nonsense.
anamnesis

Yes, that's pretty well the conclusion I had come to when I first tried. I haven't got back to it yet to test some of the other ideas thrown around here.

It could be tinned copper, perhaps I just hadn't scratched deep enough to expose the underlying core.

As for not getting hot enough, that is why I explained that I used the iron tip on the underside of the cable, and then melted the solder onto the upper surface. It quickly melted fully, not just to a lumpy paste so surely it must have been receiving heat conducted from the coil cable, not direct from the iron?

If this is correct, it suggests I can get it hot enough, despite the large heat sink. And if I can then get back to a copper surface I should be able to get a decent joint.
GuyW

Yep, the field tail gets hot enough to melt the solder, but not hot enough for the molten solder to 'fuse' to the surface of the field tail.

The solder tip, when warming up, can reach a temperature sufficient to melt the solder too, but it needs to be a little hotter before you can tin the tip. When it's still too 'cool', the molten solder just 'pools' on the surface.

But if you have scratched deep enough, and it's still grey, it does sound like ally.

1969.
When was the copper crisis? When did it start? Ally was used a lot in this period, due to the shortage and cost of copper. Lucas may have switched to ally for a while during this time.



anamnesis

I cut a notch in the end, and it's all grey. Your reference that you sent was the first I had seen mentioning they were made of copper. Aluminium is far more often mentioned

You are probably right about the temperature, though the solder wasn't just molten, it was bouncing as a hot ball on the surface of the coil end for at least 2 minutes + after I removed the heat source.

I guess the point is it's not the temperature of the solder that's critical, so long as it is molten. Copper or brass only needs to be a little hotter than the molten solder for it to 'take'. Probably only another 10 or 20 degrees at most. But the aluminium likely has to be at a higher temperature than those metals need to be, for the solder to 'take' to it.

There will be some figures somewhere, though without any means of measuring the temperature on these parts they won't help much.
GuyW

The article that Anam posted a link to or at least the PDF file linked within does mention the need for a special solder with elements in it that can form intermetallic compounds to form to bond to the aluminium, ordinary tin/lead solder won't do it as neither of those elements form compounds with aluminium.

A quick search for replacing these brushes did turn up mention of the windings being aluminium and to not remove all the original tail so the new brush could be soldered to the original copper tail.
David Billington

Yes, mentioned earlier that I belatedly realised I should have left a remnant copper wire tail on there! Too late for me now, but might help someone else later!

Those Durafix rods I linked to say they are self fluxing for aluminium. Presumably the equivalent of flux cored solder?

I realised I do have a means of measuring surface temperatures, though I doubt the accuracy. It's one of those red spot infrared guns. My electric iron tops out at around 180 C, but solder melts on it at just 100C which is surely measuring low! So not to be trusted.
GuyW

Infrared guns, David's gonna mention that word again I keep forgetting to do with the readings you get but what is it(?).

Nigel Atkins

Twas a gift. I only use it for comparative, not absolute temperatures. We saw one used to pinpoint a missing cylinder on a V8 tvr at the Dreadnought garage, Callandar. Impressively quick spot by a young lass there. Anyone who knows the place will know who I mean.
GuyW

David will explain, it's possibly not the gun at fault but the way it's used.

Learning by yourself and your mistakes is one way to go but not always the quickest or best.

Was there an instruction / information leaflet /booklet with the gun.

If the starter is a M35G I could send you some info but I don't know if they went up to 1969.


Nigel Atkins

Definitely ally then.

Very useful thread to download and keep. I've got an old starter that I've wanted to renovate for years. This is a master class, or will be when finished.

You have to finish it now, if only for the satisfaction of not being beaten by it. Or at least I would, even though at this stage I'd be tempted to get a new one. lol.
anamnesis

Emissivity

I did see one discussion where like Guy the person removed the whole lead and found he couldn't solder it so tapped the winding and made an eye on the end of the lead. this thread 4BA mentioned near the bottom https://www.minicooper.org/mk2-coopers/post-4997/ .

Guy it's quite possible your infra red thermometer won't work well on a small item like a soldering iron tip as it'll be picking up the surroundings as well. While mine has a laser pointer the operating instructions show the pick-up cone which is effected by the distance to the object.
David Billington

David, I had considered drilling and bolting the tails on but thought the electrical conductivity might not be good enough for the high current required. But maybe that's plan D then.

The instructions for this infra red thermometer do show the cone effect, but as I am using it at close range that didn't seem relevant. The copper tip on this iron is about 2" X 1" X 5/8" and its easy to pin point exactly where I am pointing it, and hold it so that the beam is pretty close to perpendiculatr to the surface of the iron. I still doubt the readings!
GuyW

Guy if you know the solder alloy you can look up the melting point. Your temperature reading sounds well low.
David Billington

Would it be possible to draw out the end of the field wires and crimp onto them? That would take the current especially if the crimp was filled with solder.
Bill Bretherton

Yes Nigel, I already said the measured temperature for this iron for melting the solder was clearly wrong. The iron gets way hotter than the point at which the solder melts. That should be around 320C, suggesting that this iron will potentially get to maybe 500C - 600C.

Unfortunately Bill, there's not enough free length on the coil tail to get it clear of the starter casing so there's no way of getting crimping pliers on there
GuyW

Whoops, pressed edit but it was delete, have this tip (at about 2:30) about the solder running up the braids instead - which you probably already know but in case not (video frozen for a while but audio carried on).
- https://www.youtube.com/watch?v=-nMLhl2q4s8

(I have to post to test the hyperlink works, then I notice the typos to edit.)
Nigel Atkins

I did the short earthed ones by holding with long nozed pliers which seemed to do the trick.

(You will note I also responded to the message you deleted, so I could claim to read your mind as well, but I would rather not!)
GuyW

You can't even read my posts!

That remark is on two, no, three levels, let me spell them out . . .


. . . oh, he went away. :(
Nigel Atkins

Nigel,

Interesting video, I can't think why he would remove the old tail from the crimp then fill with solder and solder the new lead on top, I would have thought putting the new tail back in the crimp and soldering that would be better.
David Billington

David, yes, agreed. Far better surely. That 100A/150A/200A needs all the help it can get or it will be reduced and the junction will get hot!
Bill Bretherton

I'm assuming this would also be a problem or at least a limitation with the idea of bolting the brush tails to the coil ribbon with a 4BA nut & bolt
GuyW

David, yes, agreed. Far better surely. That 100A/150A/200A needs all the help it can get!
Bill Bretherton

David,
I'm all for a crimp as opposed to solder every time where possible/appropriate, it was just the tip about not letting the solder run up the braiding.

I'm guessing bending the grip loop out and back must fatigue it or the chap is for solder over crimp as many seem to be, bear in mind the debates here for crimp or solder, I'm in the crimp camp (your crimper jaws with symbols come to mind now).
Nigel Atkins

Those joints in the YouTube video were soldered originally, though the base tag was bent around the cable end as well, though not really crimped to it.
I didn't watch the video when you first posted it Nigel because the link started playing adverts which alarmed me so I cancelled out. I have since gone back and its good information.

Purely by chance I had used long nosed pliers when soldering the two brushes to the end plate carriers (the easy ones!)to hold the tails in place without burning my fingers. They stopped the solder from running into the braids just as in the video but that was just luck, not planned. I do just sometimes get good fortune, though it's payback time now due with these other brushes!
GuyW

Guy,
don't worry about the ads, though they seem to increase now, remember Google isn't free, it can't take over the world without massive income.
Nigel Atkins

Update, and to summarise, lest someone else treads the same path.
I was replacing brushes on my Lucas starter motor. My big mistake was to clean all remnants of the old twisted copper wire tails from their connection to the field coil, before discvering that the coil wire is aluminium and poses reall problems for making the new connection.

The solution would have been to leave short stubs of teh copper wires still atached, and then soldered the new brush tails to those.

Too late for me. The aluminium won't take solder. But there is a product called Durafix sold on eBay for "low temperature aluminium welding". It melts at a lower temperature than aluminium, but higher than normal solder and apparently includes flux compounds in the wire to combat the rapid oxidation of aluminium which is what makes it hard to solder to.

Then folowed a lot of trial and error. Cutting out the many fail attempts, this is what worked. I used the Durafix to connect a tag of copper (a bit of copper pipe) to the end of the aluminium coil wire, and then soldered the brush tails to the copper tag. The solder works at a lower temperature than the Durafix so the copper tag didn't fall off the end of the coil wire.

All back together now, bench tests Ok and has now had a fresh coat of BMC green paint
GuyW

Well done Guy! Good to know you found a solution to the problem.
Bill Bretherton

Well done.
Nigel Atkins

Thanks for those comments.
But the real solution was NOT to clean off the old connections completely. NOS brushes from Lucas included a paper slip with instructions including this advice. Unfortunately I didn't have NOS brushes. Mine were new stock items that I had bought. Although well made, they did not include any such instructions. A major ommission as it turned out.
GuyW

Good recovery.

One more thread to save on my laptop archive. 🙂
anamnesis

Just stumbled on this. MALLOY, for ally and 'mazak' welding/soldering.

ZAMAC melts at 400°C, and doesn’t change its color when heated. Therefore it is very difficult to avoid destroying the piece during its repair.

For these troubles in Aluminum and ZAMAC welding, most workshops in the past have recommended to replace broken parts with expensive new ones, rather than repairing them.

BUT FORTUNATELY TIME HAVE CHANGED! NOW IT IS NO LONGER NECESSARY TO THROW AWAY BROKEN PARTS because MALLOY has developed a range of technologically advanced products to easily and quickly repair any aluminum or ZAMAC parts.

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MALLOY 52
MALLOY 54
MALLOY 56
MALLOY 57
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MALLOY 550
With these MALLOY special products you can easily and quickly repair any piece of aluminum or zamak, without having to replace it with a new one.

This means SAVE TIME AND MONEY!

https://www.malloy.it/en/catalog/aluminum-and-zamac-welding/

https://www.malloy.it/en/catalog/products-for-aluminum-and-zamac/
anamnesis

learnt many years ago never cut the brush leads too short always leave enough on the field coils so you can solder on the new brushes. Ran a Lucas/CAV repair shop for 4 years.
Mike
M J Pearson

Anam, Mike, I have an old M35G starter with a broken terminal connection - I mean where the tail of the start of the aluminium field winding connects to the rear of the brass external screw terminal stud. It looks like the tail was soldered or brazed to a slot in the terminal. I tried drilling a small hole and clamping with a screw and nut but the ally just tears where its drilled. So maybe this malloy stuff would work. Not much room for a torch though and you'd have to be very careful.
Bill Bretherton

Resurrection.

Bill, did you fix your m35G? Does it look like this M35J?

Does anyone have a decode of the nunbers 35/45, and the letters G and J?




anamnesis

Some of it at least will be in the Archives.

I remember 35 = 3.5" diameter, and G goes back to the 1950s.

See the start of this of this vid, while I look in the Archives - https://www.youtube.com/watch?v=kmh2qZgfv1Q
Nigel Atkins

Yeap it looks like I was right to direct you to the start of that vid -
Dave O'Neill 2, West Midlands, United Kingdom - Posted 08 March 2016 at 22:25:42 UK time

"Make sure it is an M35J, not an M35G.

The brushes are quite different."

Now for the 45.



Nigel Atkins

Ah, so the 3.5 refers to the diameter of the body, not the bolt widths. Makes sense now.

And the g and j are the different brush types and placement. G on the sides and J on the ends?

Thanks Nigel.

anamnesis

M45 looks to be for bigger and/or old vehicles than Spridgets. For an exact match up you probably need the 5 digit number that starts with 2.

Just one example of a few - https://www.heritagerotating.co.uk/product-category/starter-motors/lucas-m45-family/

I can't remember what the G or J mean other than perhaps ascending alphabet sequence, was there an 'H'?
Nigel Atkins

25147 F or E.




anamnesis

This might go back too far, I saw Healy Sprite but not MG Midget, but my sight left me on the re-run. You'd be able to memorize the model numbers if not all the part numbers. - http://www.classicvehicledata.com/wp-content/uploads/2013/01/lucasstarters46to60.pdf

Or see attached PDF.

Nigel Atkins

Anam, mine was a M35G, with side positioned brushes like those in your photo.

I also have a pre-engaged type starter, though I forget what that came off. It is a M35J. Same diameter body but brushes bear end-on, onto a radial rather than an axial, commutator, so I assume that is what the , signifies.
GuyW

Yep that list does seem to be to early.

Good description at the start though, about the part numbers vs the model number. Says later ones were 5 digit with letter suffix, denotes internal changes. Which explains something I was wondering about the way it is wired.

My picture is off a Ford btw, supposed to be the same as a spitfire motor, so maybe the same as a 1500 midget.

Anyway looks like I have to renew the brushes, and was reading back over this thread for tips on confirming resistance measurements.
anamnesis

Looks to be too young for that list I cross-posted. ETA: doh! too late again.

I can't tell from the photo if it's an E or F, more likely an F as that turns up for Spitfires on a Google search (not saying that's correct though).

- ETA - Ford came up on search of E or F I forget which. -

If you turn the body to get the flash to light up that part of the part number and take a higher res photo (than appears here at least) then you can zoom in and confirm.

The site takes onboard higher-res images now than it used to.

I used to have a catalogue of Lucas service parts on a PDF but I've lost it (or MS for me) at some point.

Just one example of parts from one supplier - https://as-pl.com/en/u/25147
Nigel Atkins

Anam, Those brushes don't look too bad to me. Mine were a lot more worn than that. Do take note of the method of NOT removing the remnants of the copper tails! The original replacement brushes supplied by Lucas came with an instruction slip advising this. Unlike the Moss supplied kits which contain no such instructions. A significant omission with the result that the uninitiated can very quickly render their old starter pretty much unrepairable.
GuyW

25147E seems to come up as well, usual spread of applications.

How about this for newness - AUSTIN MINI 998 A SERIES BRAND NEW INERTIA STARTER MOTOR ARMATURE 1967-84 - https://www.ebay.co.uk/itm/224053078817

"Hi..
This is a brand new Armature and bendix (as pictured) to suit Austin Mini 998 etc never been used, 9 teeth bendix.

Stator windings and Brush gear housing were used to rebuild an old obsolete A47 Devon Van starter

Item location Catfield ( Norfolk) will post or you can collect (business hours)

Any questions please ask.."
Nigel Atkins

From MGA Guru so perhaps too early for your starter (which may be mid-70s?, or not). The code seems to relate to starter body rather than type of starter.

M = starter motor

35 = 3.5”

325 = 3.25”

418 = 4 and 1/8”

45 = 4.5”

G = Die-cast communicator end bracket or frame.



Nigel Atkins

Got brain fade - and missed edit - 1500 starters are M35J, I remembered to look in the factory 1976 Parts Catalogue, it also has "13H 559 STARTER ASSEMBLY (25079 A to H) NLA".

My eyes hurt, brain aches, time for bed Zebedee.
Nigel Atkins

Yep thanks Guy, noted. I missed your earlier post about having a G and a J type. My picture isn't that clear. My brushes are triangular in shape and ride the commutator from the back not the side.

Apart from resistance measurements, your experience with the copper to ally solder issue, is the main reason I kept a note of this thread.

I agree too, the brushes don't look too bad. But the starter just suddenly stopped working. No slowness, just stopped. Screw driver across rear of solenoid, still no starter movement. Off car, connected directly to battery, still dead.

As said, it's off a Ford, but same as a spit, and Nigel has confirmed same as a 1500 Midget. The scant information in the Ford w/s manual, only says the brushes should be min length of 11/32". About 9mm.

The 2 brushes connected to the field coils are circa 12mm long. The 2 connected to the power post are just under 10mm on one, and a bit more than 11mm on the on the other. But the shorter one is worn at an angle. So maybe it wasn't riding the commutator well enough. Unlike the side entry brushes, it's not possible to see the brushes and the commutator when the brush carrying end plate is bolted back on. Hence I wanted to see resistance measurements, but reading back, I see that doesn't help much.

Thanks Nigel. Pity the mini armature is side on brush contact. Might have been tempted.

Still unclear what numbers and letter combination, denote a 4.5 inch bolt pattern, with rear entry brushes, and a 9 tooth bendix.

Anyway, got brushes on order from ebay, £5.32 quid including postage, and the spec says they are 14mm in length. So when they arrive, I'll fit 'em and see.

Meanwhile I'll try a little bodge. Add some thin packing to the rear of the brushes to raise the height in the holders, and see if better contact on the commutator makes it spin.

Edit. According to J Twist. My starter is week 28 1978. Numbers 28 and 78 on the body after the 25147e/f.


anamnesis

Anam

No I didn't manage to fix mine. The ally tail to the external terminal had broken. I tried screwing it to a piece of flat copper but without success. It will need to be joined by a soldering type process so I've put it to one side and bought a new starter (M35G).
Bill Bretherton

Ok, thanks Bill B.
anamnesis

Anam,
do bear in mind the M35J only refers to the model and not the type or part number (25147 E or F). Assuming (always risky) the dating convention remained the same (seemed to with switches) the 1978 date seems to fit in with the model number not being on the earlier lists.

Be very careful about any cross referencing from any source (including me) as part numbers seem to be grouped together from various sources and repeated but may include errors and omissions (as I've discovered with oil filters, rotor arms and dissy caps).

Look away now - rant about sacred cows to follow.

Why did the old British vehicle industry have so many different parts doing the same thing for very similar vehicles (some only badge difference) and why have so many inconsistent conventions. Such as bloody stupid -
35 = 3.5" yet 4 and 1/8" is 418 and not 4125, or the 35 as 348 (four eighths, half inch). Old farts, back then, sticking to old outdated imperialistic measurements yet using metric fasteners inside the engine.

They could have made them at 90mm instead 3.5" and 105mm instead of 4 and 1/8" which would also make the coding consistent.

Rant over. 😅
Nigel Atkins

Anam, one thing I dud find is that the insulation between the interior parts and the casing is very suspect. Thin slivers of mica paper that are easily displaced. Specifically between the cables to the brushes, which run close to the casing, and the collar and spacer washer between the post terminal and the end plate. Worth a close look. I made some extra insulating shields from cut down plastic milk bottles.
GuyW

Ok I'll check that too Guy.

I share your rant Nigel. So many part numbers with hard to find decoding, makes it easy to order the wrong part. I've ordered m35j brushes, but if the j doesnt specifically denote rear entry, I've lost a fiver. Going by tbe pictures of the brush set, it should be right though.

Edit. Back in the day, it wasn't really a problem. You could go to a local motor factor with a good storeman and all the catalogues, and get the right part. Today all that has been largely lost, and online just makes it worse. Plus of course old bangers are obsolete, as are the parts for them 😅.
anamnesis

Been going on decades, the one that gets me, especially if explaining to a new 1500 owner, GAN, G=MG, N=two seater tourer, and A=A type engine, "no it's not an A-series, well yes they used to be an A-series engine but yours isn't, it's a type but not the same A type engine as the previous models".

Adults will accept this but a child would say "but that's just silly" your reply "no, as very clever highly educated adults have thought of this"!
Nigel Atkins

Lol. So what type did Triumph 1500 spit engines get denoted as, if at all?
anamnesis

Well that's a result. At least I know the coils are good.

My little bodge is a success. It works.

In the pic you can see the slope on one of the brushes. I'm guessing it caused the brush to jam in the holder, and lose contact with the commutator. So I used a file to level it off, and packed it from below against the spring, with a bit of thin mica I had laying around, to bring it to the same height as the other one. Assembled and connected to my battery, and it runs perfectly.

So I think I'll dodge the solder bullet. The motor looks like it's never been apart before 1977( not 78 as I said earlier). The field brushes are still 12mm long, 14mm new. So they last a loooooong time, and have plenty of life left before they reach 9mm.

The armature brushes were barely 10mm before I filed one. So I'll use the new set for those as there is no solder required, and keep the old field brushes as they are, and the new field brushes spare. I doubt I'll ever use them.

Btw.
My letter is definitely E. 25147E







anamnesis

>>So what type did Triumph 1500 spit engines get denoted as, if at all?<<

I know the 1973 GT6 engine on my bench has the identical starter to my 1500 so I surmise the Spitty is likely to be the same.
Greybeard

And here's an interesting point of contention. When I stripped it down and saw the commutator brass was flush with the segments, I assumed it was kaput. I always thought that all motors needed undercut segments on the commutator. But it seems not (depending on what you read). According to at least one workshop manual, and a lot of motor rebuilders, you NEVER undercut the segments on starter motors; partly because it isn't neccessary, and partly because the brushes are so hard (harder than the commutator) that the segments are needed to take some of the pressure, and stop the commutator wearing out too quickly.

Greybeard, I meant what descriptive letter(s) if any, were used to describe the 1500 engine. A for up to 1275's, B for bigger 4 pots, and C for 6 pots. Hkw are Triumph engines described?



anamnesis

Oh,I see. I'll double check when I get home.
Greybeard

Anam,
it's A that's my point, the Midget 1500 is G - A - N - 6.

A = 'a' Triumph engine.
Nigel Atkins

Yep I understood you Nigel. But what are Triumph engine series actually denoted by, when they were in a Triumph?

Example, Ford have kent, Essex, Pinto etc. Did Triumph engines also have letters or names?
anamnesis

I can't remember for sure so looked it up in Terry Horler's book, it's still for sale you know!

Good job I looked it up as I'd remembered wrong, Mr. Horler informs me - PE94/J (Triumph Spitfire 1493cc) FP prefix to engine number..

FM prefix engine is taken out of a Spitfire (not the one with wings tho'), YC prefix Triumph 1500TC or Dolomite 1500.

I can't remember Gold or Silver Seal but I'm pretty sure it'll be in Archives cos we looked it up for Chris's (or someone else's) engine a couple (3?) years back.



Nigel Atkins

So it could have been GFPN6 or GFMN6 or GYCN6.

No wonder they stuck to GAN. 😉
anamnesis

Well they couldn't put GTN could they. 😀
Nigel Atkins

The FP, FM and YC are triumph engine number specifications, rather than engine type. They are equivalent to the Austin engine numbers like CE, CJ and V rather than the model (chassis) numbers which is what the AAN and GAN numbers relate to. To follow your logic, the model number wouldn't be GAN for a 1275 Midget, but GVN.
GuyW

Shiny new brushes. A goodly difference in length. Good value @ £5.32 inc postage.


anamnesis

Is that how they are upplied - ready attached to the terminal post? Mine were just loose, but were the side contact sort where the end plate terminal post is fused to one end of the field coils, and one pair of brushes to the other end of the coils. Yours looks like an easier system to replace the brushes on!
GuyW

Brushes in, motor back in, engine started. If I'd had new brushes to hand, the whole job, remove motor, fit new brushes, replace starter, would have been less than 45 minutes. Amazing.

Yep attached to the post. I don't know if all M35J are supplied this way though.

Anyway, because the field brushes had so little wear, I haven't had to use the new ones, as in the picture, so luckily avoided the hassle you had.

But learning from your experience anyway I could have left copper tails and soldered to them.

I knew it was a thread worth saving. I just didn't expect to need it so soon. 😄






anamnesis

Guy,
you're right I got mixed up and didn't give it enough thought.

So if we take the A-series engine models as GAN what should the 1500 engine be, I supposed with BL logic a Triumph engine in an MG called be called an 'A type' engine keeping GAN.

According to this site (unless I've cocked up again) for the Triumph Spitfire commission numbers "Always 'W' for 1,493cc engine". - http://www.triumphspitfire.nl/identification.html#commission

So could the 1500 be GWN, or something else.

ETA: Anam, so what does the J stand for then. 😄


Nigel Atkins

Anam

Well done on the repair.
Bill Bretherton

Thanks Bill.

Nigel, I'm still not entirely clear if the J only signifies rear entry brushes. When buying the brushes, that is how they are sold. Either g or j type. But I read somewhere, maybe something you linked to, that the j denotes something about the rear bracket(end cap), rather than the brushes specifically. Clear as mud.

https://www.ebay.co.uk/itm/180997374139?epid=27025909662&hash=item2a2448c0bb:g:hYwAAOSw-JtcbDiG

Note it says.

M6 Stud Terminal. Actually the stud turned out to be 1/4 unf. Go figure.

anamnesis

Yeah, crossing referencing info can be a minefield.

Same for modern old vehicles, looking for a neighbour to get a particular washer jet for his 2008 car and all the cupboards seem bare, there are some similar looking fixings on a later model but not listed as fitting the 2008, now do you trust the photo and take the gamble. I would but I'm not my neighbour. Hopefully an overnight soak might free things up.
Nigel Atkins

This thread was discussed between 17/12/2020 and 28/04/2021

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