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MG MGA - Prothane Polyurethane Bushing

I received my Prothane Polyurethane Bushing Set from Moss and found that they do no have a metal insert as shown in the catalog, that the bolt would go thru. Has anybody installed these? what should the tourque be?
WMR Bill

Front or rear? I have just installed the Prothane bushes in the rear spring shackles (fit like a glove). I have left the original style Silent Bloc bushing in the front eye as these were fine.
Mike
Mike Ellsmore

If you are talking about the front control arm and upper shock arm bushings I have installed them on both my MGA and MGB. I used the red ones on the B and there was a black set (not necessarily Prothane brand, but polyurethane) available frtom Moss that I used on the A so that they would look like the rubber ones that fail so quickly. I just installed them as in the Haynes manuals and they have both fit and worked out very well.

Ralph
Ralph

Bills question was torque. Torque would be what ever the size nut calls for 7/16 20 would be about 30 ft LBS. You are tightening up against the shoulder on the shaft. The nuts use cotter pins to secure. The danger of over tight is to the threads. The bushings don't care. How "tight" the bushings are is a shape and size issue not a torque issue.
R J Brown

Thanks Guy's. I installed the rubber ones about 2 years and K miles and they have disinigrated. I thought I was over touquing them because they became very distorted. RJ, are you saying I need to tighten them untill the washer is torqued against the shaft?
WMR Bill

Yes, Fully compress the bushing.
The car MUST be at ride height to tighten the bushings. Don't tighten the nuts when the wheel is off the ground and at full suspension drop. The twist is bad for the bushings.
R J Brown

With the red Prothane bushings maybe tightehing at ride height isn't as important as they are lubricated on all surfaces with a very sticky grease (supplied with the bushings).
Mike
Mike Ellsmore

Poly bushings without stainless sleeves will not last as long as they should. Rubber bushings twist, and therefore don't need a pivoting surface. Poly bushings however do pivot on their inner surface, and without a smooth surface to ride on they will become scored and suffer an untimely death. I would at least make sure the bolt they ride on is as smooth and well lubricated as possible. Or, return them and get some Superflex bushings which cost a bit more but are the best I've personally used.
Steve Simmons

I feel a little mis-led by Moss on this one because there Pic on the site and in there catalog clearly shows a sleeve with the bushing.
WMR Bill

My experience with polyurethane A frame bushings is limited, I have nylatron bushes in my car, but I do have them on the sway bar and it moves nearly as much as the A frame and without sleeves it shows no signs of wear in 10 years of use. Personally I wouldn't worry about the lack of sleeves, just tighten the nuts with the weight on the car and the proper silicon grease and you should be fine. As Steve said, definitely make sure the bolt or mount surface is clean and smooth though.
Bill Young

This thread was discussed between 02/04/2009 and 06/04/2009

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