mazdaverx7

I took out all four plugs and cylinder #4 was full of coolant...

snb13

So, to clarify, you do the intial torque, then come back and turn each nut 90* twice (in the proper sequence?)

Van

Yes, that's right. I do three distinct, separate sequences. First at 15 ft/lbs. Then I put my socket on a breaker bar, and starting the torque sequence over again, do each one 90 degrees. Then, by now I'm starting to work up a sweat, so I might rest a few minutes, drink some beer, and then do another torque sequence where each nut gets another 90 degrees.

snb13

Thanks for the last response. For further clarification, according to Clark's Garage, I see the old torque values (15, 37, 66 ft/lbs.) as well as the updated values you mention for the turbo. However, there are a couple applications that apparently spec 15 ft/lbs, 60*, 90*. Why the variances?

I ask all the questions because I'm about to drop a rebuilt head on my '83. I don't want to do it more than once.

mazdaverx7

I went with the 66 ft/lbs value as my final torque spec and I believe this is where I went wrong. With cylinder 4 full of coolant it leads me to believe that there may be a sealing issue somewhere in that area and that it is isolated to that cylinder. It gives me more of a specific area to inspect, though I plan to inspect the entire surface area on all cylinders. I plan to take the head back to the machine shop so that they can inspect it and ensure that the sealing surface is 100% flat.

StoogeMoe

Hey Van, I agree the 90 degree method is more accurate, but I was wondering what the equivalent torque value you applied on that last pull. I wonder if it's close to the 90Nm.

Mazdaverx7, I don't know if this was mentioned earlier, but have the machine shop pressure test the head. Hopefully, if there's a crack, they will catch it.

mazdaverx7

I spoke with the machine shop today and they said that I can bring the head up and that they will look it over at no cost. So, while this does suck that I have to get into the engine again, at least I believe that I know its my fault (if no parts are cracked) and I know how to remedy the situation. I also ordered a new head gasket and cam tower gasket today. Things will be easier this time around.

fejjj

Sorry you are having to deal with all this frustration.

I have had similar experiences with DIY and I know how discouraging this kind of stuff is!

mazdaverx7

I believe I found my problem today. It appears that I failed to properly torque the last three of the top nuts that secure the head to the block. Seems that the compression blew the gasket apart on the left rear. I take full responsibility for the oversight and I am still unsure how I missed those three nuts. Seems they were only torqued twice instead of three times. So, the new gasket should be here in a couple days and tomorrow the head goes to the machine shop to be thoroughly tested and resurfaced if necessary. The good news is that I did not see any cracks in the block. Here are a couple pics of the gasket. Will post more of the head and block tomorrow morning:

lart951

That looks like detonation

william_b_noble

when you reassemble, check the cleanliness of the gasket area carefully - it may NOT be the actual torque that got you but either a flaw in the gasket or a piece of something pinched under or above the gasket.

mazdaverx7

The plan is to clean the head a little and run it out to the machine shop this morning for a recheck and surface prep is necessary. Then I am going to reclean the block's mating surface and get it prepped for the head to be reinstalled. Waiting on new gaskets to come anyways so I can take my time with the prep work.

austin944

I had something similar happen on a different kind of vehicle. The engine ran, but I found coolant in the cylinders. It turns out the machine shop had milled the surface with too rough of a finish. I bought a cheap hand-held surface roughness gauge that allowed me to do a very loose eye-ball comparison of the head's roughness. I was told that some machine shops don't have much experience with heads made from more modern materials. They just assume that something that works for a Chevy will work for a Porsche. More info at:
http://www.enginebuildermag.com/2007...-heads-blocks/

wildcat077

You guys have me worried now ... lol
I just finished reinstalling everything after replacing broken rings on three cylinders and i haven't attempted to start the car yet,going to pressure test the cooling system tonight to see if there's any water leaks and fire it up tomorrow !

I torqued everything according to the Porsche workshop manual ...

Cheers
Phil

Noahs944

Maxdavex7, Well that didn't take you long buddy. Maybe this will help: use a paint pen or sharpy & mark the stud one way for first turn, then another for the second (my marks look like and X when I am done).