Poly bush recommendation?
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- Minor Addict
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Poly bush recommendation?
I’ve been reading about rubber v poly bushes on these forums. It seems to me poly is much more robust. Having noticed a couple of rubber bushes on my front suspension starting to perish I’ve decided to replace them all with poly ones.
My question is, are some poly bush kits better than others?
I was looking at the kit ESM sell for around £15, which seems reasonable to me. Can anyone testify to its quality, or offer an alternative recommendation?
My question is, are some poly bush kits better than others?
I was looking at the kit ESM sell for around £15, which seems reasonable to me. Can anyone testify to its quality, or offer an alternative recommendation?
Re: Poly bush recommendation?
I fitted the same kit to the front (and another to the rear). They are very easy to install and make a significant improvement to the directness of the handling. Not that its a great handling car but it does makes it better. Dont expect it to be like a sports car, rock hard and pin point accurate. But its no longer a wooly barge .
Highly recommended
Highly recommended
Re: Poly bush recommendation?
I fitted the same kit too and combined with some thicker oil in the dampers the handling and ride was transformed. The poly bushes did start to groan a bit after a while but I assembled them with a silicone spray lubricant when I should have used red rubber grease. I've fitted grease nipples to the top bushes as part of a re-build (the bushes were perfect and were re-used) so once the car is back on the road I'm hoping for less groaning and more enjoyment. On the tie rod it is recommended that you use a poly bush in front of the bracket and a rubber one behind to give a little compliance under braking.
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- Minor Maniac
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Re: Poly bush recommendation?
Poly bushes are the way to go.
Not all poly bushes are the same. Some are hard and some are soft. Overall the reliability of the poly bush far exceeds the original Morris Minor rubber bush.
Most poly bushes are about 70 - 85 Shore hardness (revised having found my test results) irrespective of the colour. I am in the process of fitting Super Pro poly bushes to the Spax tele damper eyes fitted to the front of my Minor. Much better than the rubber ones supplied with the kit. Will also be fitted to the rear when I get round to it.
Red grease is best but general purpose grease does not seem to do any harm. The Super Pro bushes come with a silicon type grease.
As above regarding the tie bar bushes - poly bush at the front (to assist brake loading) and a rubber bush at the rear (to assist in articulation) Red grease on the rubber bush.
Not all poly bushes are the same. Some are hard and some are soft. Overall the reliability of the poly bush far exceeds the original Morris Minor rubber bush.
Most poly bushes are about 70 - 85 Shore hardness (revised having found my test results) irrespective of the colour. I am in the process of fitting Super Pro poly bushes to the Spax tele damper eyes fitted to the front of my Minor. Much better than the rubber ones supplied with the kit. Will also be fitted to the rear when I get round to it.
Red grease is best but general purpose grease does not seem to do any harm. The Super Pro bushes come with a silicon type grease.
As above regarding the tie bar bushes - poly bush at the front (to assist brake loading) and a rubber bush at the rear (to assist in articulation) Red grease on the rubber bush.
Last edited by philthehill on Sun Jan 23, 2022 7:56 pm, edited 1 time in total.
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- Minor Legend
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Re: Poly bush recommendation?
Dont expect miracles some are stiffer than others
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Re: Poly bush recommendation?
I did a shore hardness test on the various bushes in the photo above which included a NOS BMC rubber eye bush.
These are the results:-
BMC Rubber bush...............................60 Shore
Yellow bush........................................75 Shore
Red bush............................................85 Shore
Black bush (1)....................................75 Shore
Blue bush...........................................90 Shore
Black bush (2)....................................75 Shore.
The Black bushes came from different suppliers but may have the same manufacturer.
I did use a genuine Shore Hardness gauge when testing the bushes.
These are the results:-
BMC Rubber bush...............................60 Shore
Yellow bush........................................75 Shore
Red bush............................................85 Shore
Black bush (1)....................................75 Shore
Blue bush...........................................90 Shore
Black bush (2)....................................75 Shore.
The Black bushes came from different suppliers but may have the same manufacturer.
I did use a genuine Shore Hardness gauge when testing the bushes.
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Re: Poly bush recommendation?
Thanks for all the replies, and for the tip with the poly/rubber combo on the tie bar. I’ll give the ESM poly kit a go. Rubber just doesn’t seem to last.
All noted regarding red grease on the poly.
This might be a stupid question but once they’re fitted will they need more red grease applied to them periodically? Obviously I’d still be putting grease (I use Castrol moly) into the grease nipples at the appropriate intervals regardless.
I’m going to replace the oil in the shock absorbers at the same time, any advice on what’s the best stuff to use?
All noted regarding red grease on the poly.
This might be a stupid question but once they’re fitted will they need more red grease applied to them periodically? Obviously I’d still be putting grease (I use Castrol moly) into the grease nipples at the appropriate intervals regardless.
I’m going to replace the oil in the shock absorbers at the same time, any advice on what’s the best stuff to use?
Last edited by MorrisJohn on Mon Jan 24, 2022 10:49 am, edited 1 time in total.
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- Minor Maniac
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Re: Poly bush recommendation?
Fit grease nipples where possible and grease on a regular basis.
Below is a photo of the eye bolt when fitted with poly bushes and a 45 degree grease nipple. Also see panky's photo above regarding the lubrication/grease nipple of the top pin bushes.
As regards the dampers - drain and refill with a straight 30 oil.
Below is a photo of the eye bolt when fitted with poly bushes and a 45 degree grease nipple. Also see panky's photo above regarding the lubrication/grease nipple of the top pin bushes.
As regards the dampers - drain and refill with a straight 30 oil.
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- Minor Addict
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Re: Poly bush recommendation?
Thanks Phil. How do you fit a grease nipple to a bush?
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- Minor Maniac
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Re: Poly bush recommendation?
Only fit grease nipples where possible - not possible to fit a grease nipple to a bush
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Re: Poly bush recommendation?
I did wonder! I have grease nipples on my track rod ends, upper trunnions, lower trunnions…as well as one on the drum plate backing plate (I’m not actually sure what purpose that one serves?).
Is there anywhere else they should be fitted in that area of the car?
And can I just continue to use moly grease on them as I have been doing once the poly bushes are on?
Is there anywhere else they should be fitted in that area of the car?
And can I just continue to use moly grease on them as I have been doing once the poly bushes are on?
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- Minor Maniac
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Re: Poly bush recommendation?
I think that you will find that the grease nipple on the backing plate is a bleed nipple.
The Minor in ex factory is fitted with a generous amount of grease nipples.
I would suggest that the use of moly grease on a poly bush is perfectly ok.
The Minor in ex factory is fitted with a generous amount of grease nipples.
I would suggest that the use of moly grease on a poly bush is perfectly ok.
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- Minor Addict
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Re: Poly bush recommendation?
That explains why I couldn’t get any grease in there yesterday - oops!!philthehill wrote: ↑Mon Jan 24, 2022 11:18 am I think that you will find that the grease nipple on the backing plate is a bleed nipple.