Dougs951S

Well...this all started from trying to repair the ****ty shifter linkage after it pulled the threads out. I'm ready to drop the tranny, the only thing holding it in now is the rearmost of the two allen head bolts that clamp the tranny input shaft to the TT inside the bellhousing. The bolt head rounded off (its in there so tight I couldnt budge it with a 4 foot breaker bar) so I started to cut flats into the round head to try and get a socket on it. I don't own a welder, what can I do?

MB968

A pipe wrench is a great tool for rounded head bolts, the kind with teeth in the jaws that clamp down harder on the round pipe the more force you put on them. They work great for a hex head, or on the outside of a triple-square too. I'd use some penetrant on the bolt overnight before trying to remove it.

Dougs951S

problem is its inside the bellhousing, can't really get anything on it. I just bought a torch, and I cut a hex shape into the round head so I'm hopeful I can remove it in the AM.

FRporscheman

You have very few options that you would like. First, try to shove a torx bit into the stripped allen bolt. Aim it on there as squarely as you can, put an extension on it, and bang it in with a hammer. I hope this works. Be sure to spray some penetrating oil on both ends of the bolt. Maybe you can even spray the middle of it, and tray to get it to run onto the threads.

Other options:
Long drill bit? Never tried this.

Since you got one bolt out, unmount the tranny and slide it back as much as you can, then stick a sawzall between the two bellhousings and chop the coupler in half -- DON'T f*** up either shaft. I have done this, and it sucks, big time (on 968s, the couplers are cast iron and get stuck all the time, even though the bolts come out just fine).

Get a dremel and a big pack of cutoff wheels, stick it into the bellhousing and slowly eat away that bolt head. You will likely muck up the coupler, so be ready to buy another one. If the dremel doesn't fit in there, maybe a long flexy extension for the dremel would work.

Drop the rear suspension, make the engine ready to tilt, and lower the tranny with the TT still stuck to it, until the tranny can finally be pulled off the TT shaft.

mytrplseven

If you decide, once more, to modify the bolt and twist it out, I'd recomment soaking the thing and the coupling with bolt blaster (or whatever it's called) overnight and then use a propane torch to heat the collar (not the bolt) before trying to remove it. You might also consider tightening it a hair before going the other way to remove it.

PorscheDoc

If the head is still on, take a sharp long chisel and a hammer and start knocking the head counter clockwise. Have had to remove numerous bolts this way. Hasn't let me down yet.

Dougs951S

I'm concerned about cutting it, not sure exactly where the two shafts are. I figure if I cut between the 2 sets of slots in the coupling, I'll be ok? In any case I already cut the stuck bolt and by all accounts the tranny should already be out, the trans will slide off the TT side coupling but its stuck fast on the tranny end, so I don't have enough room to pull it out. I seriously considered cutting the spare tire well to get it out that way. I'm going to need a new/used coupler, does anybody have one for sale?

MB968

On my 968, the coupling in bell housing was stuck on the internal spline. I had to pry it forwards and backwards on the spline shaft to get it to slide all the way back so I could change the clutch. I don't recall exactly how I got it to move all the way, but I'm sure it involved a pry bar on the coupling, using the access hole for leverage. When I got it off, the only thing that was keeping it from sliding on the spline was dirt/debris. Not sure it that is your problem.

william_b_noble

take a drill, preferably a left hand drill. Also take a center drill. Use the center drill to get a starting hole as near to the center of the bolt as you can, then using the left hand drill bit, (and with the drill turning counterclockwise), drill into the bolt.

Second choice. Turn the coupler so the place where the head was is directly away from up (straight up). as above, drill a centering hole and then drill through the threaded end of the bolt with a drill that will cut into the threaded area. When you get through the coupler, the bit will suddenly move easily, take it out, use a drift to tap the remainder of the bolt out and then the coupler will be free.

The bolt not only tightens the coupler, it goes into a slot in the shaft, so even with the coupler loose the coupler won't slide off if the bolt is in there, it has to come out.

Dougs951S

Yup, just realized this tonight. The bolt is cut but it still wont come free, even the unthreaded portion is badly seized. I'm going to have to drill it I think unless I can completely destroy the coupler enough by cutting the square where the threads are to allow me to basically knock it off the tranny shaft without damaging the trans.

FRporscheman

When the tranny and TT are mated, there's only about a mm or 2 between the two shafts, and this gap is near the center of the coupling. If you were to back the tranny off to try using a sawzall between the two bellhousings, then just aim a little bit forward from the middle of that coupler.

I hope the drill works out.

When you install the new coupler and new bolts, use antiseize paste on the bolts!

culture

i had the same problem. ended up getting an air chisel and using it to spin the bolt backwards. the second bolt still wouldn't budge so i ended up using a dremel with cutting wheel and cut through the bolt. no damage to the splines and a new coupler was in order. fortunately, it was cheap on ebay and came with new bolts.

it was the biggest PITA for the whole clutch job. hope you get it out without too much headache.

Dougs951S

I just got a 14" long drill extension and a carbide end mill (I'm not playing around anymore!) this sucker is getting cut out most likely sometime wednesday or thursday.

culture

i tried that too. it was hard to line it up and drill it straight. even if you drill the head off, the bolt won't come out. hopefully your plan works, but in the end, i had to cut it in half and then pry the non threaded side out. i threw myself a party when i finally got it off.

GL

Dougs951S

edit: misread post. Yup, its going to be A party alright. I'm prepared for this, I've got plenty of beer