TR2/3/3A TR3A Front Suspension question

[JFeher]

I finally have my frame painted and I'm preparing to reassemble the front suspension. I bought the urethane "magic kit" from TRF for all the new fasteners and hardware. Everthing is very straight forward as far as reassembly, except for the nylon bushings that fit the lower wishbone arms to the inner fulcrum pins on the frame. It's been a couple of years since I took it apart and I have all the old bushings. They just fell apart when I removed the wishbone arms so I have no idea what the proper fit is. I have the Triumph service manual and it shows rubber bushings not nylon. Were these something new for the TR3A? Should these bushing be such a tight fit? I could press them in along with the metal sleeve but I'm afraid of damaging them. What type of lubrication do they require if any? It seems odd that there are grease fittings all over the suspension but not at these points. Any advise with be greatly appreciated.

 

[TR3driver]

The bushings were changed to nylon shortly after the introduction of the TR3 (and recommended as a retrofit to earlier cars). The stock nylon bushings aren't very tight, usually you can push them into place with your fingers. But the urethane ones may be deliberately tighter. I used a bench vice to press the Nylatron ones I use into the A-arms, and then reamed them a bit for a tight fit over the sleeve.

Smear the pin with grease before installing the sleeve, then smear the sleeve before installing the arms. The poly doesn't really need the grease, but it will help keep the other components from corroding, and hopefully prevent the annoying squeak that sometimes develops with poly.

It is possible to drill & tap the A-arms for grease zerks; but I'm still not sure if it was a good idea or not. If you zoom in on this shot, https://i258.photobucket.com/albums/hh260/TR3driver/TS13571L/DSCF0002_ZERKS.jpg , you can see just the tip of the front A-arm zerk peeking out from under the idler arm.

 

[JFeher]

Thanks Randall. The lower wishbone bushings are nylon and the upper a arm bushings (fulcrum pin) are urethane. I thought it was odd that they went through so much trouble to put replaceable sleeves with grease fittings on the trunion side but went with nylon on the inside. I bought urethane bushing lube from Energy Suspensions for the uppers and the rear spring bushings. I think it's basically silicon grease. How do you think that would work with the nylon bushings?

 

[TR3driver]

There is a lot more force at the outer end, which I'm guessing is why they used metal bushings out there and rubber/nylon inside. As you saw, the original design was only rubber inside; the nylon was an afterthought. I'd guess that whoever came up with that modification (because the rubber bushings wore out too fast) was told not to change the A-arms.

The urethane lube should work fine on the nylon, if you have enough.