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MG MGA - Rubber or poly?

HI All.
I have just noticed my wishbone bushes are a bit tired. Should I replace them with standard rubber or upgrade to poly?
Interested to hear people experience with the poly bushes.
Thanks.
s page

Simon

I have upgraded to MGB V8 bushes on my B. It seems the MGA uses the same bushes as the MGB.

It feels a lot better than it used to with standard bushes, but I’ve no idea how long the rubber will last.

No idea about poly.
Dave O'Neill 2

Personally, er, trust was has been for many years piss-poor rubber in many items or trust that things have now improved, er I'd go against piss-poor rubber.

In my present midget I've had newish at the time rubber bushes changed to yellow MGOC bushes (not sure they still do them) and it was an improvement changed those to Super-Flex (9 years ago) and better still. The Super-Flex are still fitted and they seem fine but I wouldn't really know for sure unless I changed them.

From my experience of other rubber parts I'd say the rubber bushes wouldn't be as good from the start and they'd probably have lasted from months to a couple of years before they needed changing (if they lasted than long!).
Nigel Atkins

My preference is for poly, partly for sharper response and also because current rubber bushings are garbage and don't last very long. If you get poly, try to get the type with a stainless inner sleeve. Rubber bushings squeeze in and expand, and flex as the suspension moves. Poly does not flex, it rotates on its inner surface. So if the metal surface it's riding on is less than perfect, the bushing will wear prematurely.
Steve Simmons

Many thanks. Poly it will be.
s page

V8 rubber bushes are good value in a B
Normal B bushes are 2 piece rubber things fitted from either side, but the v8 bushes have a steel inner sleeve and the rubber is one piece so doesn't squoosh out the sides like the others
It will feel a lot better on the road with these as Dave says and you don't have to keep lubing them up like you have to with the polly bushes to stop them squeaking

willy
William Revit

Hi Guys. Thanks for all your advice and as I don't want to keep lubing squeaking bushes I have ordered some V8 rubber and steel bushes.
s page

I haven't had any trouble with squeaking poly bushes. There was one set that would squeak in very cold weather, but I've had rubber bushes do that too. And rubber will squeak when they get old and dry, which happens a lot more quickly than it used to thanks to cheap modern rubber. Nothing wrong with V8 bushings of course, it's a decent compromise.
Steve Simmons

+1 on the poly bushes with inner stainless sleeves as Steve recommended. I had to seek them out from a smaller vendor, but I think Moss carries them now. The main issue with the "standard" poly bushings (which may contribute to the squeak some report) is they do not flex like the original rubber bushes, so the trunnions they pivot on (or possibly the hole in the wishbone arm) end up being wearing surface, which they were not really intended to be. The stainless sleeve gives a designed wearing surface.

I even managed to use all poly bushes for my sway bar, which is a 5/8" diameter MGB bar mounted in original MGA location above the extension. They poly end bushes are relatively available, but the inner bushes were not as easy since the only ones available are rubber and intended for the 9/16" diameter MGA bar. I eventually found a standard bushing out of one of the poly bush manufacturer's catalog that could be made to work. I took pictures and will probably get around to posting them someplace at some point.

-Del
D Rawlins

Just checking my service records. MGB GT V8 type bushings installed in my MGA July 19, 1995 at 61,761 miles (after restoration). Today's miles at mid day fill-up, 431,691, so 22-yr 7-mo 370,000 miles, and still hanging in there. I'd call it good.
barneymg

Hi.
I have just stripped the front bushes out and as it turns out they were V8 bushes already. I have no idea when they were changed but I decided to change them as they were starting to look pershished but 3 of them were not too bad. However one is seized on the pivoted so I am glad I found it. I have taken the arms and spring pan to be sand blasted and hope to have all back together by Monday.
Thanks for all comments.
Are there any tricks for reassembly?
s page

V8 bushes are a very tight fit in the wishbone arm (well they were last time I itty some), so the trick for reassembly is a big vice to press them in place
John Bray

I nearly went with the V-8 bushings also... What really made up my mind was I received a bad "silentbloc" front leaf spring bushing where the inner steel tube was not bonded well to the rubber. Those bushings appear to be made the same way as the V-8 bushings, so my logic was that just because the V-8 bushings were once good, it didn't necessarily follow that the currently manufactured ones were still that good. So I went with the poly bushings instead.

-Del
D Rawlins

Apologies for spelling error

V8 bushes are a very tight fit in the wishbone arm (well they were last time I fitted some) so the trick is a big vice to press them in place.
John Bray

Good info on those bushes, wouldn't touch the modern rubber stuff myself, So can someone tell me where they get Poly bushes plus the stainless steel sleeves,Part number would be good Mine is an MGA

Thanks

George
George Mills

George, I think they may actually be made in Australia; the ones I used are Superpro brand. The only negative that I can see is they are blue in color instead of black, but once assembled that's not very noticeable. Certainly nowhere near as obvious as the red bushings Moss shipped me would have been.

I didn't use the Superpro bushes for the rear suspension, mainly just the generic black ones that move on surfaces that weren't originally designed to see motion. The only place I used any of the lame red bushings was for the front leaf spring mounts; those DID come with an internal sleeve, and they are buried deep where they will never be seen.

-Del
D Rawlins

George-Dell
"some" manufacturers use the colour of the poly bushes to identify the hardness of the poly
e.g.
"A royal blue colour distinguishes the COMFORT range from the red of POLYBUSH CLASSIC."
Royal blue is supposed to be about the same as the original rubber guys
But that can't be relied on as some just sell them by colour

Simon
The steel sleeve in the bushes needs to be able to slide freely on the pin , polish the pin up if you have to-
When you're fitting your bushes to the arms, don't lube them as they will keep creaping around in the arms, If you have to lube them,best to use hair spray, it lubes well to get them together then completely dries out--best stuff ever-
Just press them in till they are centred up nicely in the arm and when the spray dries, that's where they will stay.
When you're bolting it all together, leave the nuts that secure the bushes in place loose, these need to be tightened up with the arm in it's loaded position otherwise the rubbers will be twisted and will fail early
Easiest is to drive the car up on ramps when you're done so that you can get under it while the suspension is loaded up, then tighten the nuts and pin them , doing it this way, the bushes will be in a nice neutral position

willy
William Revit

Also, when you poke the springs up in their tower, make sure they locate around the locator and don't sit on top of it---
William Revit

Dell do you have a part number for the Superpro bushes for the MGA wishbone, Superpro only list them for MGB but I heard they are the same as MGA.

Regards

George
George Mills

George-
Same as--

MGA MGB SUPERPRO POLYURETHANE LOWER INNER WISHBONE BUSH KIT - BHH1123SPK
William Revit

I probably have the invoice in a box somewhere in my garage, but I have moved since I reassembled the chassis and have only been able to do a few things on the MGA, other than preparation of the work space. My new shop is almost in order now so hopefully I will be back at it soon.

Hopefully William's info was what you needed. If you need more let me know and I can go digging.

-Del
D Rawlins

> When you're bolting it all together, leave the nuts
> that secure the bushes in place loose, these need to be
> tightened up with the arm in it's loaded position
> otherwise the rubbers will be twisted and will fail
> early

That brings up another advantage of the poly bushes with the internal sleeves... You don't have to leave them loose until the car is fully assembled. Just tighten them up and install the cotters, since they don't operate on the flexibility of the material like the rubber bushings. Which may not be that big of a deal; I just hate leaving fasteners loose for however long it takes me to finish the rest of the car.

-Del
D Rawlins

This subject could go round and round in circles forever
My personal choice is the later(V8 as they are known) bushes
I'm not completely against the poly bushes but have found that after driving in wet conditions the lube does get reduced and they get noisy and need dismantling cleaning and regreasing.-which is something not needed with the V8 bushes
Anyway,-each to their own
willy
William Revit

Thank you all for your input, duly noted
Regards
George
George Mills

This thread was discussed between 16/02/2019 and 27/02/2019

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