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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 - Antifreeze

Remind my ageing brain cell please. I used to just buy blue Glycol in a 5 gallon can that lasted years. Only it's now run out.

What I think might be appropriate these days is call Oat, which is what I make my morning porridge from. But is this right for an A series engine? I want basic that just works, not a fancy 'waterless' one.
GuyW

Afternoon Guy.
OAT (Organic Acid Technology) antifreeze is formulated mainly to inhibit corrosion in modern engines which tend to be (a) more lightly built than traditionally and (b) more likely to contain a mix of different metals, like light alloys, than an old engine.
It will work fine so long as you don't mix too much of the differing types in the coolant circuit, but it's comparatively expensive (because it tends to be sold premixed as opposed to needing mixing with water), and offers no real additional benefit in your use-case. (Unless you have eg: an aluminium cylinder head).
Plus you can still buy Bluecol ethylene glycol antifreeze. It's about 22 quid for 5 litres on Amazon, or 55 quid for 20 litre.
Delivered.
ETA: additionally, OATs come in different formulations, recommended for different engines, which is why they are sold premixed. They come in different colours, mainly red, orange or pink, for this reason. You're not supposed to mix them beyond a certain small percentage so on balance I'd say that for your use-case they're a bit of an unnecessary complication.
Personally, I'd stick with the trad stuff myself.
I imagine Willie knows more than me about it.
Greybeard

Thanks Grey, this OAT stuff just sounds too complicated. As I said, I just want basic!
Bluecol it is then. I will try our one remaining indie motor factor and if they don't stock, then it will have to be the dreaded Amazon. I really try to avoid Amazon if at all possible. Principles, you know!
GuyW

I bought some 'blue' antifreeze from ECP, after having difficulty finding Bluecol. Then my heater stopped working and I found some nasty looking crystals in my heater tap.

Having flushed everything out and replaced the heater tap, I bought some Millers Alpine blue from my local mg specialist.

https://www.opieoils.co.uk/p-77238-millers-oils-alpine-blue-antifreeze-coolant-concentrate.aspx?srsltid=AfmBOopGJJ-WZKhDCXE0208I2DmdC4ZG6M_d8cf7qrOH188fUMwDoK_X




Dave O'Neill 2

I think (?) Blue Star is another acceptable coolant.
Philip Sellen

I agree with Greybeard OAT coolants don't really suit our older cars--same with HOAT coolants
I'd be going for a green HAT coolant --they (HAT coolants) don't go acidic when they reach their useby date and are usually effective for 7-8 years.
Blue coolants are more for Japanese alloy headed cars where there are a mix of metals in the system, some Euro cars as well like Mercedes run Blue
Red is more for later model alloy engines/radiators-

Do you have Nulon there--Their green longlife (HAT)is a ripper, as a concentrate or premix---I go for the premix as we have truck loads of lime in our water here.
William Revit

Ebay. Smith Allan.

https://www.ebay.co.uk/itm/305839899779

Concentrate. Makes 20L.

£29.99
£6.00/L
Free delivery in 1-2 days.



anamnesis

Still confused
Halfords stock OAT, which I understand is not right. Silicate, and "NAP free" whatever that is!
Easiest seems to be to follow Dave's advice and order Alpine Blue from Millers.

Willy, Not found any of the green HAT stuff here
GuyW

Guy
Something I forgot to mention earlier---
OAT coolants (usually red) are believed to effect high lead content solders as used in brass radiators/heater cores and are therefor not recommended for earlier model cars. I believe it's a very slow process of gradually eating the solder away--haven't actually experienced it but have heard of it.
Another thing--make sure you flush out your old coolant if changing type/brand---If it turns out they're uncompatible they form crystals that don't circulate and clog up the cooling system.
A prime example of this is the VW coolants, they're up to version #12 now which will mix with all the others except #1---During the evolution of these there were combinations that mixed and others that wouldn't like---"(don't quote the numbers example only)"-maybe 2 would mix with 4 but 7 wouldn't mix with 3 etc ---a real pain when they were very similar colours.

Shame you can't get the Nulon longlife stuff, I think Penrite make it as well,but a few more dollars ,but, they advertise it here for 500,000 Klm (no time limit)service life. Might be worth chasing that up-
Penrite is an Australian brand but I think it's available in UK
willy
William Revit

Yes we get Penrite - is this the stuff?

https://penriteclassicoils.co.uk/product/7-year-blue-coolant-anti-freeze-premix/

[Edit] perhaps not, as it says it is OAT...
AdrianR

A bit confusing this Oat stuff.

The Smith Allen I linked to earlier says,

"
ch 41 IAT Ultra is an ethylene glycol based, ultra concentrated coolant package which has been specially formulated for use in classic, vintage and veteran vehicles. The product uses Inorganic Acid Technology (IAT) offering corrosion protection to iron, steel and lead solder and control over acidity. The coolant should be typically flushed and changed, every two years."

On their own website it says,

"This ethylene glycol-based coolant contains an Organic Acid Technology (OAT) inhibitor package and is Nitrate, Amine, Phosphate, borate and silicate free. The product provides all year-round frost and corrosion protection and is formulated for use in all engines, including those constructed from aluminium alloys


So it's got an Oat inhibitor, and specifically formulated for classics.

What's the problem with OAT then?

They also do,

Smith & Allan Blue Antifreeze NON OAT.

Product Info

Description
Antifreeze BS 6580 is an ethylene glycol based coolant concentrate, which is formulated for use in all engines including those constructed from aluminium alloys. The product provides year round frost and corrosion protection and contains an inhibitor package that is free from nitrates, amines, phosphate, borate and silicate. The product exhibits exceptional thermal stability and hence eliminates the risk of deposits particularly near the cylinder head, engine block, radiator, water pump and heat exchanger. The product also contains a bittering agent.

https://www.smithandallan.com/product/smith-allan-blue-antifreeze-4486

I'n not sure what's in my Sprite now. I'll have to check.





anamnesis

From the FBHVC.

Coolant - what are the choices?

Technology moves forward and new products are constantly being launched with claims to improved formulations and performance. There are some alarming stories around with relation to the use of some of these in historic vehicles which go beyond the well-known tendency of antifreeze to find the tiniest hole and cause leaks and in some cases lead to catastrophic engine problems.

Read on here.

https://www.fbhvc.co.uk/coolant

anamnesis

All I want is a can of antifreeze, not a can of worms!

When any work on an engine requires coolant to be drained, my usual habit is to refill with plain water. This is in case there are leaks, or I need to drain again for any reason. In theory, once tested and passed, the water gets drained off and I refill with antifreeze. In practice this may well end up being some months later or indeed not until the first frosts arrive in the autumn. That's where I am now at!
GuyW

Just checked what I have in mine.

Probably got it at my local parts, or eurocarparts.

Bog standard etheylene glycol.






anamnesis

Just checked what I bought last time. Like you Anam standard etheylene glycol but Silverhook blue straight from the company in nearby Romford.

Trev
T Mason

Ok--
A straight OAT coolant isn't recommended for soldered radiators and it's usually red
Green hybrid coolants are the go
Blue hybrid coolants are ok but more suited to the alloys used in Japanese and some Euro cars
We don't use much blue coolant here like you guys seem to be--it's used mainly in Jap. cars
Green standard glycol are the norm but they're usually limited to 2 years before needing changing out.

A green hybrid HAT(hybrid acid technology) or green HOAT(hybrid organic acid technology) would be best choice as they give the same protection as basic green glycol coolants but by being hybrid mixes of glycol and AT coolants they give the advantage of protection ,long life and don't go corrosive after a couple of years like standard glycol coolants do

Here's the latest release from Penrite

https://penriteoil.com.au/products/green-oem-coolant-concentrate
William Revit

It has occurred to me that antifreeze is a bit misleading in the discussion of OAT, HAT etc. The antifreeze bit is ethylene glycol, sometimes propylene glycol IIRC non toxic but more expensive. The HAT, OAT etc is the corrosion inhibitor package to protect all the various metals in the coolant circuit.

I've got some Bluecol on order but that's for the TIG torch cooler as I have to strip it down and it's due for a change. I'll likely have some leftover for the engine when needed.
David Billington

Anam

That Triple QX was what I had from ECP.
Dave O'Neill 2

Probably where I got mine too then Dave.
anamnesis

David, you're 100% correct---but that moves the discussion on to another can of worms- which I'm not sure anyone wants to get into here------

Yes, glycol is the antifreeze component of most all antifreeze coolants and the technologies HAT HOAT OAT etc are more modern developments to tailor the coolant to specific needs like longer life for one and various protections for various metals-----------This coolant(antifreeze) is known generally as a type A

Type B coolants on the other hand have reduced glycol content and offer little or no anti freeze, anti boil protection , they are mostly used for corrosion prevention.

Sorry Guy, didn't want to get into this side of it as I presumed you needed an antifreeze based coolant-

I'd look for a glycol(type A) coolant and if you want to go for one that lasts for more than 2 years look for a longlife hybrid mix preferably HAT 1st choice or HOAT but definately not OAT

willy
William Revit

"All I want is a can of antifreeze"

I seem to remember I used this stuff, or similar, when recommissioning the cooling system on the midget:

https://www.halfords.com/motoring/engine-oils-and-fluids/antifreeze/halfords-silicate-antifreeze-and-coolant-ready-mixed-5l-216235.html

I got concentrate, not ready mixed. No issues with it from what I can see after a few years, no "tiny leaks".
Tim Carter

I love the protection. It tastes bitter. 🤣🤣.

Yep concentrate much better value


anamnesis

I hadn't heard of people drinking antifreeze, unless possibly it were alcohol based. But there are lots of instances of pet cats dying from drinking the stuff. Presumably because they can't read the label, though I am not sure how they manage to unscrew the bottle cap.
GuyW

Ebay - https://tinyurl.com/5586tcb5

Bluecol Blue Antifreeze Coolant Long Life Concentrated Ethylene Glycol -36C 5L £22.94 incl postage.


Jeremy MkIII

So what about the aluminium rad in my Sprite? I have ordinary Bluecol in it. Crystal clear after 3 years.
Les Rose

Thermostat housing?
Csrb manifold (1500 version)?
Water pump - some versions

All alloy based.
GuyW

I have used Bluecol for years and all the ally parts are fine
Bob Beaumont

Come to think of it now though, my thermostat housings have often suffered from corrosion, particularly the spout.

And I've always only ever used bog standard blue antifreeze; often bluecol.

anamnesis

I've decided not to comment on this any further as it's just going round in circles

You do realise Bluecol is just a brand name like Castrol or Wynns or whatever and they do a full range of coolants green blue red and their latest is dead clear and mixes with any of the others
Saying you use bluecol means nothing really, that in itself doesn't describe what type of coolant you have or if it's the correct one for your car/required service interval length.
And don't forget if you're using a 2 year coolant, it has to come out after the two years as it eventually goes off/acidic and corrodes stuff up way worse than just plain water.

willy
William Revit

Come to think of it, a few years ago I had a thermostat housing corrode right through.
Les Rose

Yep, I think we all know bluecol is a brand and not just a type.

Could be right about its life in service though in my Sprite.

I can't say I drain and refill max 2 years. More like top up, and drain flush every half dozen years. 🙄.

Probably explains my thermo housing corrosion then. 🤪. But seems ok at the mo', and I 'think' I have a new spare --- ?

Seem to remember new crossflow 1275 Spridget thermo' housings were a bit thin on the ground not so long ago. Were they? Are they?






anamnesis

Is there any sort of test that can be done to check the state of the coolant, like a Litmus test.
David Billington

I have only ever tested antifreeze with one of those specific gravity testers - the little pipette things with the 3 coloured density balls.

For my modern, the handbook just lists the antifreeze type as "Blue. (OAT)" No other details at all, not even the concentration though I suppose that is up to where you live.
GuyW

I renew mine every 2 years as per the manufactures guidance and the thermo housing etc is as good as new. perhaps having longer change intervals causes more corrosion potential??
Bob Beaumont

David - yes a litmus test is fine ,you can get a little packet of litmus strips for the job, we used them a lot. There is a neat little tester that you can buy cheap not much bigger than a pen, battery powered and has a row of lights up the side indicating the state of the coolant.

Guy your modern would have aluminium radiator and heater core with no lead solder--interesting it specs blue coolant----Is it a Japanese/China car=
William Revit

This talk of antifreeze has got me thinking - I haven't changed mine (in the Frog) since initial filling after rebuild, early 2021. So it needs changing I think.

I haven't drained an A series for a long time now. I'm sure I just used to pull the bottom hose. Is that OK? I don't recall ever loosening the block drain tap. The (vertical flow) rad drain tap might shear - I don't want to risk that.

But what about disposal? You're not supposed to drain antifreeze into surface drains are you? I know we all used to, but what do people do now?
Bill B

Drink it Bill. Tastes a bit bitter, as said above.

But filtered through your kidneys, it won't harm the environment when you flush it affer taking a piss;; as I might be. 😉.



My local council takes waste oil and antifreeze etc. Free unless in commercial quantities.


anamnesis

🤣🤣🤣
Bill B

Bill,

I’d be interested to know if you reveal any corrosion on the thermostat or water pump stubs when you change the antifreeze. The recommended period is routinely stated as 2 years between changes, but corrosion might also be dependent on whether you used tap water (pretty hard in our region), deionised or distilled.

I always drain the rad by using the bottom tap, and then the rear block drain tap for the engine.
Philip Sellen

Bill - I forgot to add:

I’m presuming you used new thermostat and water pump, so any corrosion would be quite obvious.
Philip Sellen

Philip
Will let you know. I'm not being negligent (!) but time has a habit of running away and I tend to exceed recommended intervals anyway. I have a 20 year old Volvo V70 which has had the same coolant since at least 2013 but I was led to believe that Volvo specified coolant (which it has) was for life (dealer doesn't change it) but I'm now going to take advice from a Volvo indi garage I use now and then.
Bill B

I have an anti-freeze tester that I use for my car’s then top up if necessary. I am alone in using this tool.
Alan Anstead

If that's the tester that measures the relative specific gravity of the antifreeze solution with 3 little coloured plastic balls in a pipette, , then no, you are not alone Alan!
GuyW

The corrosion inhibitors are clearly important and testing the pH must be useful. I've read it should be 7.5 to 10, no lower, in the alkaline range.
Bill B

Well I've drained and flushed the Frog now. I know why I left it so long but why I should have done it sooner. The radiator drain doesn't work so I pulled the bottom hose and collected the very rusty coolant (never used to).

Removed T/stat housing, which came off easily, to flush engine. Some corrosion in housing as shown in picture (it was new early 2021). Hope w/pump is OK. Spent an age trying to re- attach bottom hose (but we all know about it....).

Yes, I should have done this before now, but I hate the damn job so put it off.

Question now is, should I leave system empty for the winter or fill it? 50/50? Was only about 25% antifreeze but the anti- corrosion agents have clearly deteriorated. Will do a pH check.






Bill B

Gosh, thats a bit alarming Bill, if that t-stat housing was new just 4 years ago!
I really would not have expected the neck part to be almost corroded through liked that. They should last for years with little sign of corrosion. Given your modest use of the car it looks like that housing is another of these poor reproductions made from toffee.
What coolant were you using?
(I still haven't done mine)
GuyW

These appear to be steel.

https://s-can.co.uk/product/thermostat-housing-miglia-style/





anamnesis

Thermostat Housing – DIY Weld on stub

£54.00(incl. VAT)

This thermostat housing is offered for those who need the outlet pointing in a non-standard direction.




anamnesis

Guy
I used softened tap water (about 70%) and standard antifreeze. I was surprised at the corrosion too, never known anything like it (Moss part). I've put it back on, it should last a bit longer hopefully with new coolant - might get some distilled water (never have before).

£54 a bit steep Anam. Maybe I'll just accept the housing is a "sacrificial" part.
Bill B

It's the coolant going off that's caused that---I've seen radiator caps, heater taps, metal heater pipes and freeze plugs rotted away after about 4 years-Water pumps seem to survive for some weird reason--longlife coolant is the answer if it's not going to be changed regularly(2 years).
Had a mate with a Dino that was going into storage, normally you'd just drop the coolant out and leave it dry, but he changed the coolant to a good known brand 2 year one---5 years later he went to get it out of storage and it wouldn't turn over on the starter, he tried a new battery, starter motor etc and eventually found a cylinder full of coolant--the dead coolant had actually eaten through one of the cylinder heads, on pulling the engine apart it looked like someone had been into the heads/block with a gas torch, and a bent conrod for good measure---well and truly stuffed would describe it.
William Revit

You've convinced me to change it after 2 years Willy! Maybe I should check the w/pump.
Bill B

Just changed mine last week after many years and low mileage- all looked good - standard Bluecol Blue back in - roughly 50% I guess.

I do wonder if there is also an electrolytic corrosion going on as well with all the dissimilar metals ? And some likely dodgy alloys nowadays. Aluminium being way down on the scale.

On most smaller boat engines there is provided an anode - ok especially on raw water cooling - I always ran one even on indirect cooling - I wonder if it would help on our engines ?
The drain plug probably could be adapted to house a small zinc.

richard b

I'm inclined to think electrolytic corrosion is involved Richard as well as what Willy said. Never known that much corrosion on a newish part or even an older part in the past and I seem to remember sometimes running with water only in the summer and you put a bit of antifreeze in, maybe 10% the night before the first hard frost was forecast.
Bill B

Would electrolytic corrosion be influenced by whether it was positive or negative earth car?
GuyW

The answer is probaby in one of these Guy.

https://www.corrosionclinic.com/corrosion_A-Z/polarization.htm

https://www.safe-skipper.com/galvanic-and-electrolytic-corrosion/

But I seem to recall, pos earth is worse than neg earth where electrolosis is involved. But if only chemical, not relevant I think.

anamnesis

It seems strange that the thermostat housings always seem to be erroded.
Would be interesting to know the composition of the alloy as Zinc is often alloyed in Aluminium to enhance certain properties.

Have seen a brass nut and washer dezincify on a forged bronze bolt to such an extent that it looked like an aero chocolate bar ! not good for a stem bolt on a wooden yacht! Obviously builder cutting corners !
I may still have it somwhere in the workshop I'll have a look.
richard b

Anam, one of the ofentimes cited reasons for the change from positive to negative earth was to reduce electrolytic bodywork rusting with, I think, the car body acting as an anode with positive earth. I could well have that the wrong way round?

I was just wondering if the same effect might be happening with the engine itself being connected to a positive earth early car.
GuyW

I should be posting anonymously and I'll probably be called bonkers again as I'm a bit embarrassed to confess to not having any antifreeze in my Sprite.

I have a couple of litres of Bluecol that have been waiting to go in for a long time and I have had several good opportunities to add it when I the system has been drained. Sadly, each time I've drained the system for jobs such as changing the timing cover oil seal, I have not wanted to put the antifreeze in until I was sure there were not leaks combined with the fact I was also pretty sure I would be needing to drain it again in the near future and didn't want to waste the Bluecol.

I've just started dismantling ahead of doing various jobs on the engine and gearbox so the first thing to do was drain the radiator. The picture shows what came out (bar what went on the floor) after 24hrs for the sediment to settle out. This had been in the engine for over 18 months. The bolt is in the bottom of the bucket just to show the clarity of the water.

I have always used distilled water from our dehumidifiers and I'm sure that has helped to minimise corrosion. The car is always garaged and I keep a close eye on the weather forecast through the winter. When frosts are forecast the car is covered and a pipe heater goes under the engine. It has survived some nights of -8C (one of which burst the pump on a jet wash in another out building).

I intend to put the Bluecol in this time - when I'm sure there are no leaks.

C



C Mee

I used dehumidifier water in mine, but I was told that it wasn’t a good idea by folks on the MGB forum. Can’t remember why, exactly.
Dave O'Neill 2

dehumidifier water is just full of germs from the air , might be ok mixing with concentrated coolant but to use it straight there'd be a strong chance of growing a radiator full of all sorts of germs i'd think
William Revit

Legionnaires' disease?
anamnesis

I've always used dehumidifier water just like distilled water. After all, its been evaporated then condensed.

I used to live near Hadrians' Wall. Legionnaires' disease was rife. Wiped them out, though we were ok.
GuyW

Well I've used softened tap water up to now but the aluminium corrosion has put me off so I'll get some de-ionised water on this occasion. Cheap enough and we don't have a dehumidifier although, in winter, we use a condensing tumble dryer with a tank which produces distilled water, I think.
Bill B

Very good Guy 😁
(Nice one, centurion lol).
One reason for using glycol or whatever in the coolant is that it is a better coolant than water. Some engines used neat glycol, not for it's antifreeze properties but because they required more efficient cooling
I'm thinking of high power piston engines for aircraft; IIRC including the RR Merlin although I believe the detuned Meteor version didn't need it.
I have a book somewhere on the history of the Merlin - I'll have to look it up.
Willie hit on another good point. The antifreeze also inhibits the growth of nasties like specifically Legionnaire's.
This can otherwise turn up in the expansion vessel, but by far the likeliest place to find it is in the screenwash reservoir, so it's important to use additives there.
This was something that featured on the course I used to teach for volunteer mechanics in the LifeBoats and it's a real "thing", not some kind of urban myth.
Richard (I think) raised the question of anodes. Quite right. Virtually every boat engine I ever worked on used them. The Caterpillar 3412 had two in the heat exchanger vessel and positively ate the things. They were about 4" long and 5/8" thick and would be 50% consumed in around 3 or 4 months.
A common mistake I found people making was taping the threads of the anode plugs. This broke the metal to metal contact with the steel vessel and virtually stopped the anode working. This became something I checked immediately on every CAT engined boat I worked on.
But I have the idea in the back of my mind that anodes for freshwater systems are a different composition to those used in saltwater environments.
Greybeard

Greybeard
Certainly the exterior anodes on the boat hulls have different composition for salt, fresh and brackish waters.
I don’t know about in the engines being different - think Volvo only listed the one - will check when I find the parts book I still have somewhere !

I remember well having a stainless steel water trap on a rubber exhaust pipe and I made a large silicon bronze plug to screw into the drain hole - the excess threads into the trap were eroded within a couple of seasons and the whole bolt virtually gone within a few more - hot salt water erosion speeded up any galvanic corrosion - amazing to see.

So does the radiator temp increase the erosion ?
richard b

Good point Richard. Anode composition is dependent on where it's fitted. Many small marine diesels didn't have a freshwater cooling circuit and simply pumped saltwater around the engine. An example is MD series Volvos. The downside was the weight penalty - the engine castings were very hefty to cope with the erosion.
The CATs also had their anodes in the saltwater side of the heat exchanger but for corrosion protection in the rest of the engine relied on the very expensive longlife coolant called CAT ELC. I think I only ever had to change it once in 23 years involvement with them.
Hull and shaft anodes are a different matter as you say.
And you're right about high temperatures exacerbating erosion. I remember it being a big issue with hydraulic oil coolers for offshore winches and so on, which frequently needed their cooling hose fittings changed because they fizzed so readily especially in the Arabian Gulf with the high salinity. Didn't matter if you used carbon steel, bronze or stainless - they all got eaten!
Greybeard

Lol Guy.

But maybe wrong millenium. 😉

French?


Mais non.

Trust the Yanks. Lol.

The disease is named after the outbreak where it was first identified, at a 1976 American Legion convention in Philadelphia.



anamnesis

Used to service a guys boat for him, it was a 34ft Riviera with twin Volvos--He bought 2 new props for it, nice big 3 blade stainless jobs. the shaft anodes were pretty crook and the boatshop only had one, so fitted the new one and the best of the old pair. All good back in the water. Would have been 3 months max. later he rubbed the thing on the bottom and snapped a rudder shaft, up on the slip and couldn't believe it one and a half props, the second hand anode had completely gone and the blades of the prop were eaten away just leaving three little sticks. Asked him what it'd been going like and his answer was that one of the tacho's had been playing up and reading high-----wonder why.
William Revit

PMSL at that Willie!
I had a bloke complaining that his engines were not revving properly and pouring black smoke. Perkins 4108s IIRC.
The boat engineer he usually used told him it was down to bad compression and the engines had to come out for rebuild. He was devastated as he was about to go on his two week summer cruise.
I asked him if the engines started alright. Yep -on the button.
Nothing wrong with the compression then.
Next question: when did you change the air filters?
It doesn't have any he said.
Wtf?
So I had a look and found that all it had was steel mesh strainers in the inlet pipes, hidden away. He didn't know about them and had never cleaned them in 15 years. They were completely blocked.
Ten minute fix and a happy boat owner.
😁
Greybeard

Nothing like a happy boat owner Grey.
This bloke with the Riviera would have to be the most un-boat fella you'd ever come accross, he just shouldn't have had a boat. The marina where he kept it was horseshoe shaped and the Riviera had a white hull with a maroon strip up around the top near the deck probably around 8"wide. All the boats down in the bottom corner where the wind blows to had maroon strips rubbed on them--he was useless---bit harsh, he was a ripper bloke just shouldn't have a boat.
He wanted to help service it one day so sent him to drain the engine oils while I started lubing/adjusting the steering,throttle,gear cables, it had double everything with controls inside and also a flying bridge.---He arrived back out of the engine room saying sorry, I think I broke that little box again--He was doing it all the time, wouldn't look where his feet were going climbing down into the engine room and stands on the volvo wiring connector box on top of the engine--ggrrrrrr--prick of a job repairing that. but he was happy he had the oil draining. So I goes for a look, the engine room is lined out with about 4" thick creamy coloured foam, he'd set the pump up in the dipstick hole ok and the hose into the waste oil drum but when he'd climbed out had stood on the pump and cracked the hose--When I looked in there the pump was going flat out like a sprinkler, irrigating the nice clean sponge around the walls with nice black oil--what a mess--thanks for the help
ok you can laugh now -- or do you want more

Actually meant to say before, when we first put the new props on the thing it went from 24knots flat out to 28--good value,made a fairly quick boat out of it, they were funny looking things with really wide blades that all half overlapped each other. They certainly jerked her into gear that's for sure-----but you need 2 lol
willy

William Revit

I am now thinking that my corroding t/stat housing progressively became the sacrificial anode in the ageing coolant. I'm definitely going to use deionised water with bluecol about 50/50 and completely change it after 2 years.
Bill B

Anyone got a volume for the coolant on a 1275 with X flow rad?
GuyW

Book says 6 pints.
richard b

Thanks Richard. Not at home, where handbook resides!
GuyW

Until it fills to the level marked on the external expansion tank Guy. Must admit, I didn't know it was 6 pints.

And, even pulling the bottom hose, doesn't drain the block.

I noticed today another level I should attend to. Oil.

Bad oil is corrosive too. I should probably do an oil change before it gets too cold for me to bother. I should/would have done it before now, but I buggered my thumb. Changing my oil will be a good test to see how useful my hand is now.

anamnesis

Greybeard,

"One reason for using glycol or whatever in the coolant is that it is a better coolant than water.". Both ethylene and propylene glycol while used as coolants either neat or mixed with water have a lower specific heat capacity than water and so are a poorer coolant but do give the advantage of increasing the boiling point and suppressing the freezing point. The early Merlin engines used 100% ethylene glycol but later went to a water ethylene glycol mix possibly due to the increased specific output of the engines due to improvements including the supercharger design. I've just started to read the auto biography of Sir Stanley Hooker who had major input into the supercharger design. Many discussions about the use of EG and/or PG as a coolant with the waterless coolants around.
David Billington

Never noticed a level mark on the expansion tank Anam.

Anyway I was asking for volume so I know how much water to drain off before adding the concentrated coolant. At present its just 100% good fresh Cumbrian rainwater.
GuyW

I've got a white plastic expansion tank on my Sprite Guy. I think it must be from a late Midget. Or is the plastic an aftermarket replacement?

Anyway, see through and has a level marker.

anamnesis

1500 did use a plastic expansion tank, similar to the Austin/Morris 11/1300.
Dave O'Neill 2

Both my cars have the brass expansion tanks.
Its original on tge '71 Austin Sprite and a modification on the vertical flow rad of my Frogeye. I dont recall that style having a level marker. I just fill to about 2/3 full when cold. If I overfill it soon regulates itself.
GuyW

David B; thank you for the correction. It seems I got the wrong end of the stick altogether.
Need to go back and read the book again.

It's a family "hand down" from my grandfather that he was pleased to convert from Spitfires to Mosquitoes because the Mosquito had it's engines in the wings and didn't constantly blow glycol in your face when the pressure cap lifted.
Didn't work out too well ultimately as he was killed flying a Mosquito.
Ancient history and all that...
Greybeard

I still haven't replaced the coolant - system is empty at the moment.

Before I do, is it necessary to remove the block drain plug? It's hard to get to, the heat shield is in the way and I can't find a ring spanner that fits. Engine has done about 3000 miles since rebuild including thorough cleaning. I back flushed with a hose via the t/stat housing until the water ran clear from the bottom hose. Will that do? I'm sure I never used to bother with that damn drain plug. Old coolant was a bit rusty.
Bill B

Drain plug takes a 3/8 Whit spanner IIRC.
Dave O'Neill 2

Thanks Dave - I'm still inclined to leave it alone though. Awkward as hell to get to and get enough force on the spanner plus I don't want it to slip and cause another hand injury!
Bill B

Wouldn't have thought you need to flush it again Bill.
FYI attached is the erstwhile Mr Atkins' flushing guide.
Jeremy MkIII

Thanks Jeremy - just as well Nige isn't here to put me straight!
Bill B

This thread was discussed between 30/09/2025 and 30/10/2025

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