924Board.org

[BWW]

I've got the timing belt off and I'm ready to reset everything. Of course I can manually crank the camshaft, but wouldn't this still cause the valves to crash into the pistons? Do I need to remove the camshaft before resetting it? If so, do you know where I can find the torque sequence and specs on the camshaft bracket bolts?
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Brent
'81 931 project car

[Fifty50Plus]

No need. Slowly put crank to TDC #1 (if you run into interference, turn the cam a bit also). With crank at tdc #1, position cam so that bottoms of lobes for #1 cylinder are above their lifters. Then check alignment mark on back of cam and put the belt on.
When doing all this turning of crank make sure plugs are out and crank turns easily.
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1979 924 NA race car
1982 924 NA race car - Sold
1982 924 Turbo almost a PoS
1981 924 Turbo a real PoS, new engine
1982 924 Turbo nice body, blown engine
1972 911 E race car - going to Vintage
Various 944s to become IT-S race car

[Beartooth]

You'll only have piston-to-valve contact by turning the cam if one of the pistons is close to TDC, but think twice before you move anything. If at any point you have valve-to-piston contact, you're not likely to hurt anything unless you try to force it. If the pistons are all a half inch or so below TDC, then you can turn the cam to your heart's content. That said, you'll need to get #1 at TDC and line up the timing mark on the cam sprocket one way or another (on the back-side; it really threw me for a loop when I was trying to figure why the crank was way off when the mark on the front side was lined up with ridge the valve cover). Hopefully the cam isn't that far out of phase. If you're close to the timing mark on the crank and the cam is 180 off, you could try putting the belt on and turning the crank 360 degrees. If you contact a valve trying to get there, you'd have to take the belt off, adjust the came a tooth or two, and try it again. Keep in mind, the cam isn't "off" if it's 180 degrees out; one full turn of the crank, and the marks line up. Get the crank 180 degrees off, and you'll have big trouble. It may actually still be lined up, or just a tooth off. I'm not positive, but I don't think there's a way you can set the cam that allows for the crank to turn 360 without contacting a valve. Alternately, with the crank set forward or back 45 degrees from the timing mark (will put all pistons well below TDC), turn the cam until the marks line up, and then turn the crank until the marks line up (shortest distance). Someone correct me if I'm missing something, but there should be no chance of piston-to-valve contact that way. Like I said, you shouldn't hurt anything if a piston contacts a valve, but that's assuming it's turning slowly. Use a long breaker bar to give yourself better control of the movement. The ideal way to set things up is to set the crank at 0 degrees, then set the cam at 0 degrees, then finally, the distributor. But you can't just do that with an interference engine...
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1980 931 diamond in the rough

[BWW]

Many thanks for the input. I got them lined up by removing the belt and setting the crankshaft and camshaft individually before putting the belt back on. I kind of just went by feel to make sure there was no contact between pistons and valves.

Good news. It worked! The car started and ran (briefly) for the first time since I've had it. It still idles horribly and won't stay running for long, but it's still important progress!
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Brent
'81 931 project car

[Fasteddie313]

Very good!
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80 Turbo - Slightly Modified

[BWW]

Thanks again for the help! It's actually staying running pretty well now after adjusting the fuel trim. But...my oil pressure light is on and I have a heater core leak. Plus the cooling system needs flushed. But still, I will take it!
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Brent
'81 931 project car