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MG Midget and Sprite Technical - top trunnion fixing

Chaps..here's today's question. The pin passing through the top trunnion/shock arm takes a castellated nut which has to be torqued up to the appropriate value before being pinned and which also needs to take a screw into the end of the shock arm. Thing is, if it's torqued up first then the cutaway in the bolt through the rubber mounts may not align with the thread at the end of the shock arm..and if the through screw is fitted first the torque setting is not made through the rubber mounts.
Hope that makes sense..so..what have others done here?
Thanks as always
Dave
David Cox

Throw the castle nut and pin away

And get a grade 8 nyloc nuts... that's what came in my kit and it has worked out very well

Prop
1 Paper

..been thinking about the order of doing things:
Put the trunnion pin through with the nut loose.
Locate the screw into the shock arm to avoid cross threading issues. Leave this loose too.
Torque up the trunnnion pin nut and secure with the split pin [sorry, Prop. I'm a dinosaur..]
finally torque up the screw into the end of the shock arm
Dave
David Cox

Dave, what l did was to put the shock arm screw in first, but not tighten it up. Then tighten the T pin bolt fully and then the shock arm screw last of all. You also need to do this with the wheel on the ground (awkward) or at least with a jack under the outer end of the wishbone to mimic it's laden state.
GuyW

thanks Guy..pretty much what I have settled on..good point about loading the suspension ...don't want excessive droop!!
Dave
David Cox

And you don't want to get your trunnions in a twist either!
GuyW

Remember... when complete, and the front wheels look like Benny the walrus clapping, your tuitions are on backwards 180 degrees off

And nothing wrong with old school... castle nuts worked for 70 years or better, they will still work today
1 Paper

...all done now, thanks for inputs.
David Cox

Congrats... now if the weather was a big warmer, or a little more climate change

Prop
1 Paper

I never wait for good weather, Prop...get the roof [and your right foot] down...
David Cox

When you fit the bolt into the shock arm, make sure that the flat on the trunnion is exactly lined up with the hole, otherwise you will strip the threads right off the bolt. You will only find this out when you come to take it apart again. I have had this happen.

Dave
Dave Barrow

I agree Dave...I had to try several through bolts before I found one with the recess in the right place. Couldn't believe the variation in items meant to be the same thing. Had the same issue with cotter pins..different lengths with different degrees of shamfering. Selective assembly is the name of the game!
David Cox

whats the thread size of nyloc / castellated nut - thanks. Stuart
S G Macfarlane

got it - 3/8 UNF
S G Macfarlane

This thread was discussed between 03/02/2018 and 05/02/2018

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