Lower Trunion seized

Post by **winger300** » Tue Aug 28, 2007 8:51 pm

After unbolting both sides of the suspension legs I've found that lower trunions on both sides had seized. It was impossible to remove the pivot pin, in the end I cut the trunion off with a grinder.

It seems that since the lower trunion pivot pin couldn't move, the eyebolt bushes were so badly worn I'm having to replace the eyebolt on one side, and just caught the other side in time.

What could cause this? Lack of greasing? When assembling new ones, should I lubricate the pivot pin with something? Copper/White grease?

Also, should I grease the swivel pin threads or fill the trunion with grease before I assemble them, or assemble them dry, and grease through the nipple?

Post by **overider** » Tue Aug 28, 2007 9:08 pm

I would say smear grease on everything before assembling then when assembled put full lock on one way and pump with grease through nipples until it comes out then put full lock on the opposite way and pump with grease again this should be ample.
Worked for me

Post by **bmcecosse** » Tue Aug 28, 2007 9:42 pm

Moly grease on everything. Lots of it. The old pins may have come loose if you had heated them !!

Post by **winger300** » Tue Aug 28, 2007 9:46 pm

Probably, but the threads and trunion were shot in any case.

Post by **bmcecosse** » Tue Aug 28, 2007 9:49 pm

Ah - nothing lost then!

Post by **dunketh** » Wed Aug 29, 2007 10:14 am

How bizarre. I'd have thought the pins would loosen with age - and wear.
Mine just popped out with a tap of the hammer.

Post by **MoggyTech** » Wed Aug 29, 2007 10:49 am

Poly Bushes for longevity, Coperslip on the pins, LM grease for the trunnions = years of life

Post by **winger300** » Wed Aug 29, 2007 10:52 am

I dont think the grease ever got to them!

I've just found the fitting instructions for some old Lower link kits, and it suggests you fill the space between the metal bushes with grease, grease all the threads, pins, washers etc before assembly. My guess is that it had been replaced without greasing, and just seized up when the car was left standing for a couple of years.

Post by **wibble_puppy** » Wed Aug 29, 2007 10:57 am

MoggyTech wrote:LM grease

*warning - novice question*

is that lithium grease?

Post by **bmcecosse** » Wed Aug 29, 2007 1:25 pm

Better by far with Moly Grease!!

Post by **wibble_puppy** » Wed Aug 29, 2007 1:57 pm

*warning - another novice question*

what is moly grease?

it sounds like something an apprentice gets sent out to look for on his first day at the job, like "half a pound of left-handed nails"

Post by **dunketh** » Wed Aug 29, 2007 3:08 pm

I use LM Grease but I've no idea what it is to be fair. I put enough in so lots of it squirts out during re-assembly.
I've always called it 'bearing grease' as that's what its normally used for.

The top one:
http://www.mgocaccessories.co.uk/acatal ... e_176.html

Post by **wibble_puppy** » Wed Aug 29, 2007 3:14 pm

ah, cheers for that, dunketh!

the descriptions say that LM Grease is lithium grease.... and the next one down on the page is "moly grease" which is molybdenum grease

cool

Post by **winger300** » Wed Aug 29, 2007 5:26 pm

I just bought some Lith-Moly grease which sounds like a mix of both, does that mean its ok to mix Lithium and Moly grease in Wheel bearings, Trunions etc?

Post by **bmcecosse** » Wed Aug 29, 2007 9:01 pm

Most greases have lithium in them - but Moly is a fantastic lubricant - and of course it's a bit more expensive - but then you use so little it's not really an important extra cost!

Post by **wibble_puppy** » Wed Aug 29, 2007 9:36 pm

am i right in thinking that lithium grease is specified for applications where a high melting point is needed? it's mentioned a lot in workshop manuals etc

Post by **bmcecosse** » Wed Aug 29, 2007 10:44 pm

It's just a standard grease - not specially high melting point - no need on a Minor!