trunnions

[timetraveller]

after a recent mot test and a couple of adviseries i have attempted to swap a worn lower trunnion on the drivers side today but had a bit of a problem

i dismantled all the parts off the leg and screwed off the old trunnion and the threads were fine
when i tried to screw on the new trunnion it got halfway and started being difficult to screw so i gripped the trunnion and gave it a couple of turns with a bit of force then i unscrewed it to see what the holdup was and it had completely removed the bottom four threads off the leg ??

it doesnt look it by eye but it was like the inside of the trunnion was tapered......any ideas anyone ???
have i received a badly threaded one ?
have i received the wrong model part ?

i had to refit the old trunnion which screwed straight back on but due to the car being my daily driver im a bit concerned about driiving about with a lack of thread on the bottom of the leg

the trunnion was bought new from a morris minor dealer and wasnt cheap

thanks
Neil

[DAVIDMCCULLOUGH]

I dont think they are normally tapered, the bottom threads do wear and eventually strip and the bottom trunion falls out. I definately think you will have to fit new king pins and I wouldnt drive it too far until you have. Probably worth giving the other side a good going over at the same time.

[bmcecosse]

I can only say - DON'T DRIVE THE VEHICLE - it's now a death trap. Did you remove the cross pin from the trunnion before screwing it on ? It should run on EASILY by hand - no need for force. But that kingpin is now scrap metal - source another urgently!

[aupickup]

did you take out the pin from the trunnion first
if not then you have damaged the threads on the bottom of gthe kingpin, its a common mistake

[timetraveller]

looks like a new leg then......

[bmcecosse]

At least 'another' leg then..... Very dangerous to drive the car now - please don't do it!

[MarkyB]

It's a harsh lesson, but it's always worth checking why something isn't going on as expected before resorting to brute force.

[horrace]

whilst we are on the subject of trunnions, i was getting a knock from both sides which have i traced to the lower trunnion (n ot sure if its called this) and the fulcrum pin (not sure if its called that either) basically my lower trunnion was about 1mm smaller than the ridge of the pin so when i tightened it up there was still front to back slop, i have now put a 1mm shim in and all is fine, btw they were all new parts

[bmcecosse]