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I'm having a problem with....

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bgbassplyr

bgbassplyr

Darth Vader
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a buggered filler plug on an overdrive transmission, TR4. PO really tightened it up and apparently couldn't get it to unscrew, thus the rounded over edges.

I have tried:
7/16" open and box end wrench
7'16" 12 and 6 point socket driven on with a BFH
metric tools same as above
small pipe wrench (no room to really get it to bite).

So I'm down to drilling it to try an easy out or just drilling it out, UNLESS someone knows of something else I can try.

Thanks in advance.
 
Too late now, but you should have started with a 7/16" 8-point socket. Right tool for the job and all that.

Haven't tried them yet, but I picked up a set of bolt/nut/stud removers at Sears that look like they should work, if you can get in there with a BFH to drive them into place:
https://www.amazon.com/Lisle-19250-Stuck-Bolt-Remover/dp/B000P0TZZG

Afterwords, of course, I suggest installing a hex-socket plug, with a smear of anti-seize on the threads.

DSCF0025.jpg
 
I figured that a 4 side socket would be even better.
 
Don't have any 4 or 8 sided sockets.
Hex plug replacement for sure. Side and bottom.
Should have said that the transmission is on the bench so I can get to it from any angle.
 
Don't have any 4 or 8 sided sockets. So badly rounded I'm not sure 4 sided would have helped.
Hex plug replacement for sure. Side and bottom.
Should have said that the transmission is on the bench so I can get to it from any angle.
 
If you can square up the plug a bit with a small file or angle grinder, this might work.

Using a suitable hex nut, file out the hole to make it square. Make it a tight fit and whack it onto the plug with a BFH. Tack weld if not secure enough.

A hex ring spanner or socket with a long extension should free the little devil.

Viv.
 
Removing a rounded filler plug from my TR4A transmision was the single most frustrating, annoying and debilitating repair exercise I've ever had.

I've rebuilt the front end, rebuilt the engine, replaced the entire interior, and on and on . . . .

But removing the seats and carpeting, then the transmision tunnel, just to crouch in a contorted position for hours and drill a rounded off plug out the transmision, all the while aiming in the dead center, and dulling one steel bit after another, is something I am able to pretend was humorous only because no one was in the garage to hear the groaning, to see the expressions on my face or to hear the words I spoke.

I'm not sure how the overdrive plug will differ, but let me suggest one tiny piece of advice that may well have reduced my three-day project to one.

Drill in the dead center of that plug while assisting your eyes with a good set of magnifiers, and use only a brand new carbide 3/16" drill bit. Nothing but carbide. Maybe $10 per bit.
 
bgbassplyr said:
Don't have any 4 or 8 sided sockets.
Click to expand...
8 point sockets are readily available at Sears, Home Depot or any reasonably well stocked tool store. They do work surprisingly well IMO, even on moderately damaged square heads. Going from 8 to 4 doesn't seem to add anything, IMO.

Sometimes you have to add some force to keep the socket all the way down on the square, though. Last time I had a tough one, I had to jam a pry bar between the ratchet head and the body.

BTW, heat might help too. The aluminum housing expands faster than the iron plug. Obviously you don't want to set it on fire, but warming the entire area to around 250-300F with a torch should loosen the plug considerably.
 
bgbassplyr said:
So I'm down to drilling it to try an easy out or just drilling it out, UNLESS someone knows of something else I can try.
Click to expand...

If you get to the point of drilling, get some left handed drill bits. Quite often just doing that will get it out, before using the easy out.
 
I'd try a little heat if you can as Randall suggests. I've also had good luck with basic vice grips cranked down very tight on anything - they seem to grip better for me than a pipe wrench. Grinding flats will make it even better.
 
Can you weld a bolt to it and then use a wrench on the bolt. I had to do that on a BMW drain plug not too long ago.
 
I agree with Randall and Randy on judicious use of heat. I have some old TR gearbox cases that were given me many years ago; before that, they sat in barns or basements or garden sheds for many years. They had nice, pristine drain and fill plugs on them, but dissimilar metal reaction kept them solidly in place. No amount of leverage was going to free them without taking chunks of the case along. I wasn't that desperate, so I never tried heat, but I suspect it's the only way those plugs will ever be free....
 
I'm with Randy. If you have access to an acetelyne torch, then heat it plenty hot - and then let it air cool. Then it sounds like you will need to use vise grips at this point. Or, grind a slot and use a hefty screw driver. Heat will work every time...if you can get it hot enough...and get a grip on it.

If you cannot get a good grip on the buggared stump, then grind a flat on the end and drill it. Try an extractor in the hole you drilled. If that doesn't work, then keep drilling bigger till there is very little plug left...and re-tap. If you are careful, the tap will spin out the last of the plug without damaging the case.

If the aluminum gets too buggard...then drill the case and tap for the next arger size plug (as helicoils will leak and won't work here). If you have to keep the same size plug for sentimental reasons, then weld the hole and retap for the original size plug.

This is the standard progression in removing frozen bolts/plugs. After you have a single bolt that you have to go all the way through to the welding step...you will NEVER install another steal bolt/plug in aluminum without using anti-seize!!! That includes spark plugs.

Good luck....I've been there at least a dozen times on this TR3 restoration.

John
 
Yeeha!!!

Bought a set (only way to get them) of Craftsman universal wrenches (on sale, $20) which are supposed to do exactly what I needed, and by George, they worked.

Used the 7/16 box end driven onto buggered square end, added a short pipe come-a-long for leverage, gave a slow steady pull and out she came.

Thanks to all for the advice.
 
DNK said:
Twice the pressure area?
Click to expand...
Well, I was speaking from practical experience ... but I don't think it works that way even theoretically. Either 4 or 8 will grab the corners of each face, and neither one really grabs the center of each face.
 
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