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S1 Timing Troubles

 
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poor-sche  



Joined: 06 Jan 2017
Posts: 48
Location: Los Angeles, CA

PostPosted: Thu Mar 26, 2020 9:17 am    Post subject: S1 Timing Troubles Reply with quote

I think I screwed up. I removed the timing belt in order to replace the water pump; 2 times. The first time the car started without issue, but the replacement pump leaked. The second time the pump was water tight but the car won't start.

Just checked timing marks and my camshaft mark (dot) is 180 off from the flywheel mark (z1). The crank I rotate by hand easily, the cam only rotates about 30 with a wrench.

How do I get it back into time? Did I bend my valves?
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Paul  



Joined: 02 Nov 2002
Posts: 9414
Location: Southeast Wisconsin

PostPosted: Thu Mar 26, 2020 11:19 am    Post subject: Reply with quote

Most likely you have bent valves, but to make sure:

Remove spark plugs

Turn crank 90 degrees from TDC (this places all pistons half way down their bores)

Turn cam to its mark

Turn crank back to TDC

Install belt

Check distributor for rotor cylinder 1 alignment.

Do a compression test.

If compression is good, install plugs, start car, adjust ignition timing.
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
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poor-sche  



Joined: 06 Jan 2017
Posts: 48
Location: Los Angeles, CA

PostPosted: Thu Mar 26, 2020 1:39 pm    Post subject: Reply with quote

Thanks Paul!

Got it back in time and ran compression. All 4 cylinders consistently read 118 to 120 psi. That can't be right, can it? Put it back together and it fired right up. No weird noises no hesitations. It is idling too high however, 2,000 rpm. I'll put my timing light on it tomorrow to adjust.
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Paul  



Joined: 02 Nov 2002
Posts: 9414
Location: Southeast Wisconsin

PostPosted: Thu Mar 26, 2020 11:45 pm    Post subject: Reply with quote

Glad to help! The fact that these engines have a 7.6 compression ratio and variances in gauges and testing methods might explain your readings. I wouldn't worry since all cylinders are reading much the same.
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
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