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Posted by: hedfurst Jun 29 2008, 06:03 PM

Hello All,
Got several issues with one of my T-4 motors and wanted some ideas.

I have pulled one of the heads to have some broken exhaust studs replaced and one of the cylinders is stuck in the head! It's only been a few days but everything I've tried hasn't worked. I'm trying to be careful but that big hammer is looking more and more appealing. Any suggestions?

Also, this is a stock motor out of my 912E, runs great and is still fuel injected! I have found some clues that indicate some previous work but am not sure to what extent. Anyway, this thing has head spacers/gaskets. I don't remember finding any of these when I originally dismantled my '74 2L 914 motor. My question is whether there is a significant performance benefit to me pulling the other head to get rid of these things. How much of an CR/performance improvement will 20thousanths less deck heighth get me? Adviseable or even worth the trouble?

Posted by: type47 Jun 30 2008, 08:12 AM

well, the cylinder is a slip fit into the head so the only thing that holds the cylinder in after all the nuts and bolts are removed is the carbon from the combustion. i'd use some penetrant for a couple of days until a gentle tap from a rubber hammer frees the cylinder. i can't imagine that something would weld the 2 together.

Posted by: Cap'n Krusty Jun 30 2008, 09:00 AM

Common problem. Caused by leaking head gaskets. Before you ditch the HGs, remember you need to compensate with cylinder spacers, as your CR will go where you don't want it on modern fuel. If you go this way, you'll need to measyre the dech height and the volume of the combustion chamber, then calculate the CR. Remember also, that 914 heads ARE NOT covered by the VW bulletin concerning the elimination of head gaskets. AFIK, Porsche never issued such a memo, and the heads are different. Despite, many competent engine builders go through the effort to do it right, Jake included, and it seems to work for them. The big trick is to do the measurements, have the machine work done by a machinist familiar with T4s, and do the calculations. Set the CR where you can live with it on today's gas. The Cap'n

Posted by: dbgriffith75 Jun 30 2008, 09:45 AM

But if this doesn't work, you might try using a torch (on its lowest heat setting) to gently heat the head and cylinder, and then tapping it loose w/ a rubber mallet. Or if you don't have a mallet, use a block of wood. Just don't hit metal to metal- chances are good you will do some damage if you do.

And this is just my personal opinion/preference, but I reccommend you use head gaskets. I'm sure there's 914ers here that have gotten away w/out them and using spacers instead, but it seems to me that ditching head gaskets would have the same effect on a T4 as it would on a V8- the results just aren't pretty.

Posted by: hedfurst Jun 30 2008, 08:35 PM

Thanks for the advice gents, I've got it soaking now.

Cap'n, Grif-think I'll just leave well enough alone. Original is good. I have plans for a performance transplant in the future-- will store the original mill as is.