GT 500 - need your help with ideas on what could be wrong

[csheff]

JWH, I am running the dual points.

[sg66]

I've had the defective coil issue and trust you've confirmed they work on another motor?

One other thing to check is if you have any vacuum leaks. I had a rubber nipple blocking off a vacuum port on a Holley once that had dry rotted causing a similar experience. Visually everything appeared ok installed on the car and I only found it when I pulled the carb off to open it up and check inside.

[67350#1242]

You can run a jumper from battery + to coil +.  Try to start then.  If it does the problem is ignition switch, bad tach, or open wiring from ignition to coil.  Don't let it run too long with the jumper.
Kurt

[JWH]

Just checking in, any success getting the car back on the road? If so, what was the fix?   

[csheff]

Not yet JWH, haven't had much time lately. Going to do some work on the car Sat.

[csheff]

Ok, I have found by turning the car over, the dist. turns but I cannot feel the #1 piston come up. I thought gear on Dist but if it turns the gear is there. What am I missing?

[trotrof1]

So you have presumably eliminated fuel or spark as the problem so next  put a compression tester on it and see what pressure reading is. I cant imagine the piston not moving but you can carefully insert a wooden dowel or something similar into the plug bore and slowly turn the crankshaft by hand. When #1 piston is at the top of its travel check the timing marks on the dampener to see if at TDC. Then check to see if dist rotor is pointing exactly at # 1 on the cap. Might be 180 out so rotate crankshaft one time and recheck if necessary. I think the crank bolt is 15/16. Also when viewing the marks on the dampener rotate the crankshaft both directions and make note of how many degrees of movement free travel to see condition of timing chain. Just a process of elimination is all. Report back with your findings.

[Bob Gaines]

A quick way to check for TDC without compression testors is to use finger or thumb over the spark plug hole as I am cranking the (more like tapping) and when the piston pushes compression out (should feel it and hear the woosh) I start to verify TDC by way of the harmonic balancer markings. Not that this way is better but typically faster to see if further more in depth evaluation is needed. If you rotate the engine and no compression from spark plug hole then you know that you definitely need more evaluation. Best of luck with solving your problem.

[csheff]

Compression tested ok if 150 -180 is good. checked play in rotor again and noticed I could spin all the way around with a little force. Rotor is good and not cracked. Decided to remove points plate to look underneath. Things seemed to look good there. weights still in place. So is it possible the pin on gear on Dist. sheared?

[Greg]

Compression tested ok if 150 -180 is good. checked play in rotor again and noticed I could spin all the way around with a little force. Rotor is good and not cracked. Decided to remove points plate to look underneath. Things seemed to look good there. weights still in place. So is it possible the pin on gear on Dist. sheared?

Bingo, sounds like you found it.  Pull the distributor and look, you should not be able to spin the rotor button around if it is seated properly.

[trotrof1]

If you are saying that you can physically spin the dist rotor and the dist shaft rotates also, then yes pull the unit out and look at the gear on the shaft. I think a previous post noted a possible rollpin issue. I dont think a detached drive gear would fall off the shaft but just be gentle when pulling the dist out.

[KR500]

See reply #10

[csheff]

Rodney, what thru me on Dist pin was it spun when being turned over. But won't be 100% until Dist was s pulled and looked at

[Greg]

Rodney, what thru me on Dist pin was it spun when being turned over. But won't be 100% until Dist was s pulled and looked at

Because the gear is press fit it would be possible for the button to turn, it just would not turn in sequence with the firing order therefore not allowing the spark plugs to fire at the appropriate time. 

[trotrof1]

I was just wondering during the crank no start condition did it want to pop back through the carb or want to stop abruptly? Or did it just sound normally just no start?