Problem with tear-down

Motor Head · 03-14-2004, 03:38 PM

I need help.

I’m in the middle of disassembling my 1972 T engine and I’ve come up against a problem.

I’ve removed all the hardware and nuts holding the passenger side cam tower and all the hardware for the chain housing including the cam gear and shims.

The cam tower and/or heads will not release from the case, not even a crack. The chain housing will separate from the cam tower about 3/8 of an inch but refuses to budge away from the case.

I’ve sprayed everything with penetrating oil and used a plastic mallet persuader on the flat spot on the top of the cam tower without success.

I’m working alone and the engine is sitting on the floor with the exhaust still attached (no muffler). All hardware from the top of the engine has been removed but the oil cooler is still attached.

I expect to pull the cam tower away from the head at the oil cooler end and then slide the end of the cam out of the chain housing once I can angle the cam tower clear of the oil cooler. Or, remove the cam tower and heads as a unit (and exhaust) in the same fashion.

I’m a bit frustrated and could use a little enlightenment, obviously I’m missing something. I don’t expect the heads to just fall off but I didn’t expect this much resistance. Is there a safe place to work-in a pry bar without causing damage?

The engine has been sitting in storage for a year but it’s not frozen and everything so far looks well oiled and without rust.

All the nuts holding the cam tower and the nuts on the head studs came away without incident ( one stud unscrewed from the case).

I promise not to be offended when someone points out the most stupid mistake. I’m obviously overlooking something.

At a loss…

Damomma · 03-14-2004, 04:16 PM

Did you remove the nuts positioned below the rocker arms. You have to remove all the rocker pins and arms.

Motor Head · 03-14-2004, 04:38 PM

That's it or at least one reason. I didn't take out the rocker shafts because I was having a problem with a cheap allen set. Any suggestions for easily removing the shafts?

I'll get a new allen set and take out the rocker shafts and then the nuts positioned below the shafts.

Thanks for the enlightenment.

Why wouldn't the cam towner and heads come away as a unit with the head stud nuts removed?

john walker's workshop · 05:18 PM

the heads and towers can be removed together no problem. you first have to remove the chain housings. the end of the heat exchanger on the early cars can interfere with getting the housings off. you already gutted the housing of tensioner, idler sprocket, cam sprocket, etc, so there's only the chain left, right? to get the housing to pop off the case, pry out the outer end, which opens a gap at the top rib where it would contact the engine case. stick a screwdriver blade in the gap, and them push the end of the housing back toward the cam tower. this breaks the gasket bond at the case.

Motor Head · 03-14-2004, 05:46 PM

Thanks John, I'll try to pry the chain housing off tomorrow. I just don't want to damage the case with the screwdriver blade.

The housings are empty except for the chains and I can get the housing to move away from the cam tower by at least 3/8 of an inch or more with a couple of screwdrivers. I can see where the heat exchanger would interfere with my efforts to get a grip on the housing.

How much effort should be required to get the heads and/or cylinders to separate as a unit? Any tricks?

klaucke · 03-14-2004, 09:49 PM

I just took the cam housings/ heads off of my 74 2.7 without a problem, once I had the cam out. Having the cam out means gutting the cam towers/ chain housings, however, I didn't bother to remove these and had no problems because of it. Only thing is I had to remove/install the pistons in a certain order to access the wrist pin, and you need to slide the engine tin in with the cylinder. Because of the design of a 911 engine, you can't really remove all 3 cyinders as one bank, but it's not really a problem. The heads can be removed as one easily though.

Hope that helps.

john walker's workshop · 03-15-2004, 07:19 AM

once the chain housing is free from the engine case, it can be removed along with the head/exhaust/cam tower as a unit, as long as the chain is not hanging over the nose of the cam. when the screwdriver is inserted in the previously described gap, you just pop the housing back against the cam tower with your hand. you don't actually pry with the screwdriver, it's just a wedge.

Motor Head · 03-15-2004, 04:26 PM

I want to thank everyone for their help. I was able to remove the cam towers and heads as a unit once I got the cam out.

Couldn't remove the chain housing until I removed everything else because of an interference fit with the heat exchanger.

The biggest problem was with the small tab on the heat exchanger bolted to the underside of the case.

Because I'm working by myself with the engine on the shop floor and without a hoist or stand I found it difficult to move the engine but I was able to lift the flywheel end of the engine and let it stand on the crankshaft nut while I removed the nut from the tab holding the heat exchanger but I first removed the long studs above and below the crank nut.

My next little dilemma is dealing with the exhaust allen nuts without the special allen tool. I may have to bite the bullet and buy that tool. So far I've been able to get everything else off without any special tools. I used a 46mm socket and breaker bar for the cam nuts. I stuffed a shop rag between the chain and the gear and had no problem, very easy. I don't think I caused any distress to the chains or gears.

If anyone knows a trick to remove the exhaust allen nuts without using the special tool, please advise.

dtw · 03-15-2004, 04:32 PM

8mm allen socket from sears...

Damomma · 03-15-2004, 05:38 PM

Any hardware store will have a longer reach 8mm allen wrench, then use a good sized closed end wrench on the short end. I used my dremel to cut the bend off an 8mm allen then just used a 8MM socket and a breaker bar.

klaucke · 03-15-2004, 06:38 PM

I didn't plan to take my heads off of my cam housings, so I didn't bother to take the exhaust off of the heads. I didn't have a wrench I thought would work nicely so I said "screw it" and just left them there. Everything still cam off nice and smoothly, so if you just need to get the heads off to access something else, Iwould recommend leaving the heat exchangers as is. BTW, my engine is a 1974 2.7 litre.

Wayne 962 · Wayne 962's Garage

Quote:

Originally posted by Motor Head
The biggest problem was with the small tab on the heat exchanger bolted to the underside of the case.

Ahh funny, I was going to ask about that when I read that you were removing everything with the exhaust attached...

-Wayne