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MG Midget and Sprite Technical - Polybushing
|Right - first question.....put me right here please gents. Car is essentially a 71 mk3 midget with ...ahem...slight modifications here and there officer...However, in polybushing the rear, a few Qs.
Rear shackle bushes - Are they 4 top hats. Is it a case of removing the plates/old bushes and refitting?
Spring pads - Seems easy enough, anything to watch out for?
Front bush - Metalastic I believe? These seem to last so is there any merit in replacing them? I recall on the other Midget the plate bolts were a bit of a swine to get at...
Grease everything with the stuff supplied?
Best place to buy please. I have the orange ones in the other Midget - they seem to work well.
Thinking of leaving the front in place and polybushing the pads and the rear shackles.
Grateful thanks as always.
Can't answer everything, but here goes with my offering:
There are 8 top hat bushes and I think they usually come as a kit - I got mine from Peter May but MGOC have them as do lots of other suppliers, in different degrees of stiffness. Mine are red 'fast road' but there are softer and stiffer ones available. I seem to remember being advised to use washing up liquid to make fitting the bushes easier but that might have been for other bushes.
I had to remove the fuel tank and silencer to get my rear shackle bolts out but others can probably advise a better method.
The rear spring pads were easy - just make sure everything is properly supported.
I think you're right about the front ones being metalastic - it's a few years since I did mine but I do remember that some of them were very awkward to get in place - I vaguely recall a G cramp being deployed.
I certainly don't regret fitting polybushes for track use but the ride is quite a bit firmer on the road.
|Rather than removing the fuel tank, you can just unbolt the hangers from the boot floor.|
|Dave O'Neill 2|
|"Rather than removing the fuel tank, you can just unbolt the hangers from the boot floor."|
I knew there must be an easier way of doing it!
You certainly can - provided they come away easily enough!
|Previously I had a full set of front and rear yellow MGOC and with the FL front and rear I had full sets of Super Flex (in purple or dark blue I think*). The Super Flex I thought were better and good for road use, not too soft, not hard feeling.|
|Blue ones at the back, 8 x top hat jobbies. Blue ones between axle and spring, flat. Front ones are still metalastic.|
If you're intending to drive it hard, I'd very much recommend some kind of rear axle location, Panhard, RTL, Watts.
Also have poly top bushes in the front - these have had a marked negative effect on ride comfort.
|Thanks chaps....I would not like too harsh a ride. I don't intend top race it - so what colour to go for - or is it arbitrary?|
Anti-tramp rods fitted by the by....
|It seems red is a popular choice over the years|
With the front line kit you can adjust the shocks for the type of ride you want so that closes the gap on the type of bush you want id think
|It's guesswork really. Unless you have money to throw around you choose a colour and stick with it. I opted for blue, and although l wouldn't change for the above reason, l am also satisfied with the compromise of ride Viz harshness for fast road car on back twisty roads.|
I did rear shackles, spring pad, inner wishbones and top trunnion plus ARB bushes. I retained rear Metalastic spring mount, but shimmed it so the bush centre was held tight with no lateral movement.
|For a "comfortable" ride on the road with a standard (stock) car and doing low annual mileage is it best to stick with rubber?|
It would be, if you could guarantee the quality of the rubber.
|Dave O'Neill 2|
I thought so but I presume there's no simple way of testing rubber quality other than installing it and seeing how long it lasts. I can't help thinking that any rubber is worth a punt if only doing low mileage.
i went for the orange ones..seem to be a good compromise. If you are going to replace the shackles...not expensive, cut the old ones off and replace from the outside of the car going inwards..no need to take of tank etc
|I have ordered "deep purple" ones from MGOC. Doubtless I will become a Highway Star..... |
|Not too fast as a Highway Star or you could even become a Fireball ....|
|...and then we may see smoke on the water...Puntime over, do I grease the shackle pins on re-assembly?.. and grease anything else come to think of it? |
Secondly, whilst doing this job, is it possible to shove the axle further inboard on one side to increase the clearance between wheel arch and tyre on the nearside? Plenty of clearance on the offside...I don't really want to get the grinder onto the protruding metal lip inside the wheel arch.
|no because the axle is positively located by the hole in the welded mounting points matching up to the central bolt in the leaf spring, the spigot on the flat bush and the sandwich plates.|
Normal grease is not always good for poly material but if you buy a poly kit you should get a small sachet of silicon-based grease with it.
|Could you post some photos of your anti tramp bars? A center to center measurement would be very helpful. Thanks, John|
Aha....thanks...and I have silcon grease if nothing else materializes.
|With these colours I didn't know there were standard colours to specifications I thought one manufacturer's yellow is another's purple.|
With ordinary rubber you might be into the fire but more likely the purple ones could be super trouper.
Sorry I couldn't resist.
|I agree about the black factory rubber...it detoriates at a very rapid rate|
And would be a waste of your effort and time to replace with a lower quality product for the work involved to do this poject
I want to see a pic of your ladder bars also
|Rear ones much easier to fit than front ones IIRC!|
Getting the bushes in and then the pivot bolts through is a bit of a challenge.
This thread was discussed between 06/11/2017 and 12/11/2017
This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.