Poly bush recommendation?

Discuss other problems here.
Forum rules
By using this site, you agree to our rules. Please see: Terms of Use
Post Reply
MorrisJohn
Minor Addict
Posts: 721
Joined: Sun Jun 21, 2015 9:41 am
Location: Glasgow
MMOC Member: Yes

Poly bush recommendation?

Post by MorrisJohn »

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?
A bad day with my Volksie still beats a good day at work!

https://www.glasgowmoggies.com
Grumpy21
Minor Fan
Posts: 255
Joined: Fri Jan 01, 2021 10:00 am
MMOC Member: No

Re: Poly bush recommendation?

Post by Grumpy21 »

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
panky
Minor Legend
Posts: 1994
Joined: Wed Aug 20, 2014 4:12 pm
Location: Cheshire
MMOC Member: No

Re: Poly bush recommendation?

Post by panky »

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.

Image
Image
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Poly bush recommendation?

Post by philthehill »

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.
poly bushes.JPG
poly bushes.JPG (1.24 MiB) Viewed 1332 times
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.

irmscher
Minor Legend
Posts: 3773
Joined: Wed Jul 14, 2010 10:53 am
Location: South Manchester
MMOC Member: Yes

Re: Poly bush recommendation?

Post by irmscher »

Dont expect miracles some are stiffer than others :(
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Poly bush recommendation?

Post by philthehill »

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.
Shore gauge.JPG
Shore gauge.JPG (2.36 MiB) Viewed 1317 times

MorrisJohn
Minor Addict
Posts: 721
Joined: Sun Jun 21, 2015 9:41 am
Location: Glasgow
MMOC Member: Yes

Re: Poly bush recommendation?

Post by MorrisJohn »

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?
Last edited by MorrisJohn on Mon Jan 24, 2022 10:49 am, edited 1 time in total.
A bad day with my Volksie still beats a good day at work!

https://www.glasgowmoggies.com
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Poly bush recommendation?

Post by philthehill »

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.
Poly bushes 1.JPG
Poly bushes 1.JPG (202.96 KiB) Viewed 1269 times

MorrisJohn
Minor Addict
Posts: 721
Joined: Sun Jun 21, 2015 9:41 am
Location: Glasgow
MMOC Member: Yes

Re: Poly bush recommendation?

Post by MorrisJohn »

Thanks Phil. How do you fit a grease nipple to a bush?
A bad day with my Volksie still beats a good day at work!

https://www.glasgowmoggies.com
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Poly bush recommendation?

Post by philthehill »

Only fit grease nipples where possible - not possible to fit a grease nipple to a bush :D

MorrisJohn
Minor Addict
Posts: 721
Joined: Sun Jun 21, 2015 9:41 am
Location: Glasgow
MMOC Member: Yes

Re: Poly bush recommendation?

Post by MorrisJohn »

:D 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?
A bad day with my Volksie still beats a good day at work!

https://www.glasgowmoggies.com
philthehill
Minor Maniac
Posts: 10767
Joined: Thu Jul 19, 2012 12:05 pm
Location: Hampshire
MMOC Member: Yes

Re: Poly bush recommendation?

Post by philthehill »

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.

MorrisJohn
Minor Addict
Posts: 721
Joined: Sun Jun 21, 2015 9:41 am
Location: Glasgow
MMOC Member: Yes

Re: Poly bush recommendation?

Post by MorrisJohn »

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.
That explains why I couldn’t get any grease in there yesterday :roll: :lol: - oops!!
A bad day with my Volksie still beats a good day at work!

https://www.glasgowmoggies.com
Post Reply