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TR4/4A Lower Control Arm Front Pivot Bolt

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KVH

KVH

Obi Wan
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For a TR4A, if I put a jack under the spring pan, can I remove and replace the pivot bolt holding the control arms together?

I don't like the bolt or the trunnion I now have. I want to replace both. But I don't want to remove the spring and go through all that again.

I suppose that with the spring still in, and with the control arms bolted to the pan, that pivot bolt might be jammed in too tight to slide it out. Or, maybe just slightly loosening the pan fastening bolts would help.

Thoughts? If I just need to remove the spring, I will.

Thanks all.
 
Smarter folks than I will chime in... but I don't think you can remove the trunnion without unloading the spring.
 
That bolt is actually a long pin pressed into the trunnion. I know of no way to remove it without removing the pan and lower arms. I have ruined 12 ton presses attempting to remove the pin from the trunnion, although the manual implies it should be relatively loose fitting.
 
CJD said:
That bolt is actually a long pin pressed into the trunnion. I know of no way to remove it without removing the pan and lower arms. I have ruined 12 ton presses attempting to remove the pin from the trunnion, although the manual implies it should be relatively loose fitting.
Click to expand...

On a 4A thru the TR6 that "pin" is a through bolt, not a "pin" as stated above. TR4 back to TR2 it is a "pin".
 
Jack under the spring pan and lift enough to just lift the car. You should then be able to remove the bolt and the trunnion unless things have corroded together. Assembly is reverse. Shock will keep things together.
 
I just thought of something. There's no engine or transmission in the car. If I jack under the spring pan, will it still work, or leave it all too tight? Maybe I just take that darn spring pan back off after all?
 
You might try a spring compressor in lieu of the shock to relieve the spring pressure. Without the weight of the engine I doubt that jacking under the spring pan will compress the spring.
 
Yeah - if you can get the spring pressure under control, you might be able to use the new bolt to push the old one out. That should keep the two A-arms and trunnion in alignment. If bolt-head orientation (or originality) is a factor, you could tap in another new bolt from the other side.
 
Spring compressor goes right down the middle of the spring - there is considerable disassembly required to get to it. The frame is not heavy enough to compress the spring... a lot more mass is needed!
 
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