New Engine Install . . . Timing Issues?

Waterbury

Waterbury

True Classic
Just installed a freshly rebuilt engine into my X, and for the life of me can't get it to idle/run.

I have reason to believe it is a timing issue, but I can't seem to fix it. Nothing more frustrating than spending all this time for it to not run!

Set timing according to https://xwebforums.com/wiki/index.php/StaticTiming

1) Crank at 0
2) Flywheel at 0
3) Cam at the proper mark
4) Crank spun twice and pointing toward 10
5) Verify 10 on flywheel
6) Take disty out of motor, spin rotor until pointing at number 4 plug wire
7) Install cap, firing order 1342 (double triple check rotor pointing at 4)

Turn key, starter cranks great, engine fires up and dies right away. Tried moving disty slightly and doesn't improve anything. Using timing light to my best ability, but kind of hard when it doesn't idle.

Is it possible cam is 180 out? Would that cause the issues I'm having? would it even fire for that split second if 180 out? I am 99.99% sure the flywheel is correct, and lord knows I don't want to remove the transmission to flip it. Considering I just fit the engine and trans into the car.

Verified fuel and spark.

Sorry for the multitude of questions. Thanks for the help everyone. Willing to try anything short of setting it on fire at this point.
 
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You should be able to see if the cam is 180 out by taking the cam box cover off and checking the lobe positions. The the valves should be closed on the firing cylinder.
 
This is for your 86 with FI? I am guessing that based on your signature. The FI Troubleshooting guide has instructions for "Engine starts then stops". The whole guide is in the Wiki. You may want to work thru some of those instructions to see if you can spot the issue.
 
Agree with Eric but really need a video to see what it does. No manifold gasket or intake leaks correct? That could cause problems too.
 
Here is a quick video of the fire/die situation. Low res, but the sound is there. Slight exhaust leak directly in the center of the manifold, broke a stud during exhaust install. Have a replacement that just arrived in the mail, so will install today after work. Intake nice and secure.
 
As with the others, the fact that it fires means probably not an ignition problem and I too would start looking at the injection system.
 
I went through all of this after rebuilding my engine. The FI troubleshooting guide on the wiki was a Godsend. It will take a lot of patience but going through it step-by-step and doing all of the tests in the order it says will eventually lead you to the problem. I agree with the sentiment here that it is a air/fuel problem and not timing. If you have everything static timed properly it should start and run provided the air/fuel delivery system is functioning.
 
When I replaced the cam seal on my motor this past weekend, the engine fired right up and it wasn't till I drove it and realize the power was not right that I put a timing light on the car and found it was at 5 degrees AFTER top dead center and yet the car fired right up and idled fine although at only 500rrpm. What I'm saying is that timing can be waaaaay off and the motor will still start.
 
Will spend some time in the garage tonight, beginning the process of using the FI troubleshooting guide. Will post back here with updates. Maybe it's just starting on cold start injector gas. . . . Who knows until I start isolating the issue and crossing things off.
 
When starting the fuel pump is always energized. When rel easing the ignition key when the engine runs, the fuel pump is energized through the air flow meter because that is open. If the afm doesn’t work or is not wired properly, the fuel pump dies immidiately when the key is released. Thus the engine stops. Try running 12 volts directly from the battery to the fuel pump.
 
So after some testing it seems inconsistent spark is the issue. Putting test leads on my coil, I get 2-3V during crank. When I have one lead on pos(+) and one on engine ground, I get 7V when cranking.

New battery, good charge, have it hooked up to another car as well to make sure it's not just a battery issue.
 
Waterbury said:
So after some testing it seems inconsistent spark is the issue. Putting test leads on my coil, I get 2-3V during crank. When I have one lead on pos(+) and one on engine ground, I get 7V when cranking.

New battery, good charge, have it hooked up to another car as well to make sure it's not just a battery issue.
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I would check the voltage at the battery side of the ballast resistor first with the key on and not cranking to see if it is close to the battery voltage. You can then check with the starter cranking to compare. I would think 7V is within range of a fair battery and a 40 year old electrical system. You can also check the voltage where the ballast connects to the + coil primary. It should be a bit more than half the voltage at the other resistor terminal connected to the battery. Make all measurements with respect to ground, not the - coil primary. That can rise to very high voltages (300+) when the system fires.
 
dllubin said:
I would check the voltage at the battery side of the ballast resistor first with the key on and not cranking to see if it is close to the battery voltage. You can then check with the starter cranking to compare. I would think 7V is within range of a fair battery and a 40 year old electrical system. You can also check the voltage where the ballast connects to the + coil primary. It should be a bit more than half the voltage at the other resistor terminal connected to the battery. Make all measurements with respect to ground, not the - coil primary. That can rise to very high voltages (300+) when the system fires.
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We have lift off!! Got it started about an hour ago. Have been waiting for video to upload before posting update. Still currently uploading. Stand by for first start video, will also explain what was causing it to die.
 

Here she is. After over a year of a non-running X it sure does feel good. Idle has since been adjusted to around 800rpm. Smoke is the paint on the exhaust burning off. I was tapping the injectors at the start to make sure they weren't sticking.

Spark issue was resistor ballast. Bypassed and got great strong spark back. Video starts right after it was bypassed.
 
Waterbury said:
Here she is. After over a year of a non-running X it sure does feel good. Idle has since been adjusted to around 800rpm. Smoke is the paint on the exhaust burning off. I was tapping the injectors at the start to make sure they weren't sticking.

Spark issue was resistor ballast. Bypassed and got great strong spark back. Video starts right after it was bypassed.
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Nice work but don't run it for too long without a ballast resistor or you will burn up the coil (unless it has a built in ballast which I believe 79-> don't). With no ballast, the primary current is around 2X which means power dissipation is around 4X. The ballast spec is 0.85 to 0.95 ohms. It should be easy to find a replacement.
 
Waterbury said:

Here she is. After over a year of a non-running X it sure does feel good. Idle has since been adjusted to around 800rpm. Smoke is the paint on the exhaust burning off. I was tapping the injectors at the start to make sure they weren't sticking.

Spark issue was resistor ballast. Bypassed and got great strong spark back. Video starts right after it was bypassed.
Click to expand...

Which is kinda funny ;) because everyone said it was fuel and not spark!:rolleyes:
 
Yeah for sure. Good thing I did not put money down on it cuz I would have lost. I think Andrew had similar issue with his ignition but it was a points distributor and turned out to be the plugs if I remember correctly. Always something to learn.
 
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