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MGB MGB Trunnion Nut Removal

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tony barnhill

tony barnhill

Great Pumpkin - R.I.P
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I've an order to deliver a dozen sets of MGB stub axles by the 8th of March...am slowly disassembling them but some of the trunnion nuts don't want to come off....anybody got an idea? I'm soaking them in PB Blaster but I don't think its going to work.

Doc?????
 
What's a Trunnion? (no I'm not being stupid.. just never heard that term before)
 
HooBoi...Are you talkin' the top (big) nut or the bottom trunion thru-bolt?

Blaster, wire brushes, heat, a good "Windy" (air wrench, impact socket) are about as much as I can suggest. Patience as well. But if it ain't comin' apart after that... time for the grinder or a Dremel and some "dentistry."
 
Big top nut, Doc - I was hoping to save the nuts, oh well...unfortunately I don't have a nut splitter that large so its cutting them off, I guess

Kenny, pray you never have to remove one...its the big nut right above where the shock fits onto the "trunnion" which holds the king pin in the stub axle
 
And that job is about the worst... both upper and lower are in constant contact with whatever condition exists. MGB's have, what, seven, mebbe eight grease fittings? Six of which are trunion lube points... Keep 'em lubed on your own cars!

That doesn't help the "big" nut prob, I know... but if it pushes back the time it'll be before the J-O-B is necessary, I'll DO it.

Hate trunion rebuilds, hate trunion rebuilds....
 
The company I supply with stubs can remove them - they use lots of heat & have a special puller for the trunnions...but, I want the trunnions for my inventory (& wanted the nuts for inventory also)....oh well....
 
Of course you used a great long peice of pipe as a come along on the wrench and heated em up a bit first?
 
Unfortunately, Jack, they're all out from under the car...I am going to try putting them in a vice today to see what happens when I try my 1/2" breaker bar....but if 185lbs of air pressure won't loosen them, don't think my almost-60 muscles will either!

Guess I just deliver them with the trunnions attached...don't care about the old king pins - just wanted the trunnions.
 
Assumed they were out of the car. Mount in big vice. Get wrench and breaker bar and or power wrench ready, apply heat to nut not quite to red stage, just hot hot. HIT IT with all you got. Saw the machine shop do this to engine part, came right off. Good luck.
 
I'd have an "issue" trusting a trunion nut after it'd been cycled through that process, but it WILL help remove it. The suggestion I made re: heat was to aid in the propagation of the penetrant through the rust/corrosion. Propane heat. Not enuff to "cherry" the nut, but enough to "boil" the Blaster down through the threads. It's all a matter of how much time/effort/money ya wanna throw at it, I s'pose. /ubbthreads/images/graemlins/wink.gif
 
Doc, that's all the heat I was thinking about - out of my little propane torch...

New trunnions are almost $100 each so I'd like to keep them 'healthy' if possible.....&, yep, the company that uses all the heat to remove them, tosses them afterwards.
 
No doubt: no choice... liability issues an' all.
 
If nut is the only part heated it will expand first and break loose a bit, ie the nut and the trunnion will not expand at the same rate. Or so the book says. Aye not as hot as red please.

Trunnions, get em while there hot. Get your Trunnions here.
 
20 stub axles are lined up in pairs in front of my garage...big pile of spring perches, hubs, shocks, backing plates, etc, etc, etc off to the side...never again do I want to disassemble 10 MGB suspension beams in 1 day!
Tomorrow I've got to sort through all the stuff & toss the bad & inventory/shelve the good!
 
Well, are you going to tell us how you finaly did it?
 
Not all of them came off - about half did...lots of PB Blaster, my little propane torch, & a BFH!

Gonna tackle the ones that didn't come off tomorrow after I get another propane torch....not getting them red, just hot enough so PB Blaster runs down inside them - then I light it!
 
Flaming Trunnions - hehehehe
 
And then, and then, they shoot up in the air. Easy removal what. You have some hot gloves to catch em?
 
They don't exactly jump up, they kinda fall over when I wham the top of the king pin! Gotta make dure the flame's out before it hits the floor because they roll!
 
"Flaming Trunions" ...lol. sounds like a good rock band name...anyone play guitar?
JC
 
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