engine at #1 TDC but position or rotor has changed!
#1
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Car: 1989 Pontiac Firebird Formula 350
Engine: 350 TPI
Transmission: 700R4
engine at #1 TDC but position or rotor has changed!
Hello. I have had my dizzy out for an engine strip and had to turn crank whilst it was out. Whilst heads were off I turned crank so no.1 cylinder was at TDC and valves were just closed, timing mark was at 0 at this point.
I have since put all back together and reinstalled the dizzy but the rotor seems to be pointing to 8 o'clock....it used to point to around 5 o'clock for no 1 cylinder.
What am I missing or is this normal?
Thanks. Jay
I have since put all back together and reinstalled the dizzy but the rotor seems to be pointing to 8 o'clock....it used to point to around 5 o'clock for no 1 cylinder.
What am I missing or is this normal?
Thanks. Jay
#2
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Re: engine at #1 TDC but position or rotor has changed!
I think you have #6 at TDC, not #1, I think you need one more revolution of the engine.
#3
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Car: 1989 Pontiac Firebird Formula 350
Engine: 350 TPI
Transmission: 700R4
Re: engine at #1 TDC but position or rotor has changed!
Yes having a look that may be the case however that still puts no.1 pointing to 2 o'clock which is quite different to when I started. Any reason why this could be so far out?
#4
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Re: engine at #1 TDC but position or rotor has changed!
Maybe you didn't get the distributor in correctly.
Take the driver side VC off, pull #1 plug, rotate engine by hand with your finger over the plug hole, when you feel air coming out, continue rotating until the exhaust valve begins to top open on #1, back off a tad from there and line up your harmonic balancer mark to the timing tab...then stab the distributor.
Edit:
You'll probably need to fiddle with the oil pump drive slot as well, just use a lung screw driver to rotate it so the distributor seats in it.
Take the driver side VC off, pull #1 plug, rotate engine by hand with your finger over the plug hole, when you feel air coming out, continue rotating until the exhaust valve begins to top open on #1, back off a tad from there and line up your harmonic balancer mark to the timing tab...then stab the distributor.
Edit:
You'll probably need to fiddle with the oil pump drive slot as well, just use a lung screw driver to rotate it so the distributor seats in it.
Last edited by 8Mike9; 10-09-2014 at 01:33 PM.
#5
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Car: 1989 Pontiac Firebird Formula 350
Engine: 350 TPI
Transmission: 700R4
Re: engine at #1 TDC but position or rotor has changed!
You'll probably need to fiddle with the oil pump drive slot as well, just use a lung screw driver to rotate it so the distributor seats in it
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Car: 88 GTA
Engine: Built 355 to install
Transmission: Built turbo 350
Re: engine at #1 TDC but position or rotor has changed!
That's the way it's done, As long as you have #1 piston on TDC compression stroke with timing mark on, You can put #1 on the distributor anywhere you want. You just have to make sure #1 plug wire is on #1 on the cap......
#7
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Car: 1989 Pontiac Firebird Formula 350
Engine: 350 TPI
Transmission: 700R4
Re: engine at #1 TDC but position or rotor has changed!
Brilliant, thanks! This was the answer I could not find. Thanks so much for your help!
Jay
Jay
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