BJ8 Front End Squeak

[steveg]

Good point Steve. Worth a look see. Thank you.

Heads up for others doing this for the first time. Lining it up is eyeballed. Once both are in, pushing or tapping the pin though, one would think it would rotate both bushes to line up so the pin travels though. As Steve points out, it may be off a little.

I was wondering if how tight the nut is affects the pin rotation/friction. Too tight, possible squeak. It can't be too loose or I think the bushes may rotate from the desired position. Thoughts Steve?

Let us know the outcome so there's closure on this thread.

 

[AUSMHLY]

I removed the passenger fulcrum pin. I found it was tight when rotating it in the Delrin in my hand. The pins are new from Moss as are the Delrin bushes.
How tight should these pins be when you push them in once everything is in place and lined up.
I have to tap/bang it into the bushings.
Maybe mine are too tight?

To make sure the pin was smooth, I sanded it with 1500 then used some polish. Maybe the pins are just a little larger then they should be or they don't come as smooth as they should be?

I did try applying some grease to both the pin and inside the bush. The pin fit is so tight, that it pushes the grease completely off. I remove the pin to check how much stayed. Both bush and pin, absolutely clean, no grease. So I sprayed some liquid graphite on them. Not sure that stayed, for when I pulled the pin out, again, both surfaces where clean.

Wondered if I was tightening the pin bolt to much. So this time I tighten it just enough for the cotter pin hole to line up.
Everything is in place, tires on, pushed on the fender, no squeak.

This is a time consuming process to try each thing one at a time. Which is what I should have done. So I don't know if sanding the pin, possible lubrication (doubt it) or not tightening the nut as much as before, solved the squeak.
I won't know if any of this fixed it yet. I'll need to put some miles on her to find that out.

I will as Steve requested, follow up later with my findings.

 

[steveg]

It sounds like they're too tight and that might be causing the squeak.

You might be able to find a drill bit slightly smaller in diameter than the pin, wrap it with fine sandpaper and sand out the delrin bush bore a little in order to loosen it up just a bit so the pin rotates freely.

The castellated nut should be made up tight.

FWIW when I bought my car 20 years ago I didn't realize the upper trunnion rubber bushes were completely gone. I drove the car for several years where the pin was passing through a 3/4" hole with plenty of daylight around it. Except for a slight vibration at a certain speed, driving and tire wear was fine. My point is not to worry about a little additional microscopic clearance when you sand the bores out a little.

 

[AUSMHLY]

To those who use either the Delrin or stock rubber bushes. With a 2" spacer under the shock arm and everything is lined up, are you able to push the pin in with your fingers, or do you need to tap it in with a hammer? How tight should it be?

 

[steveg]

With a 2" spacer under the shock arm and everything is lined up, are you able to push the pin in with your fingers, or do you need to tap it in with a hammer? How tight should it be?

I'm using the Cape International offset trunnion setup, so there's no driving the pin through. It's easy to adjust without taking the upper suspension apart. Recently was readjusted as part of a comprehensive wheel alignment.

When I bought it, the bronze bushes didn't fit all the way into the recesses in the upper trunnion; the machinist who fixed that also machined the lubrication groove visible in the eccentric pin. All that took it up to $250 or so total at the time. Pretty sure it's not worth the extra price over the delrin bushings. Also, it may not give as much offset as the delrins. The pin rotates easily in the bushings.

The allen screw shows the position of the 10-32 grease fitting mentioned above.

 

[Rob Glasgow]

Roger, I have stock rubber bushings with metal internal bushes in my upper trunnions. The pin could be pushed through by hand with some effort but I believe I used a small hammer to tap it in, just because it was easier. The pin rotated freely by hand but it wasn't sloppy loose.
So I think Steve's suggestion is good. Widen the holes in the delrin bushings enough to insert the pin without effort.