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Spitfire Need help with 1980 Spitfire 1500

Arkansas Spit

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Installed new distributor this past week. When I try to start there is a thumping noise coming from the starter area. The starter is a gear reduction installed 4 years ago. The starter has been getting a workout while trying to troubleshoot other issues.

The distributor was installed at top dead center. It is an electronic ignition, 12 volt coil non ballast.
The distributor is tight to the bell housing.

The thumping noise seems to be occurring a regular intervals. New clutch was installed 3 years ago and there was little wear to the timing gear.
 
Installed new distributor this past week. When I try to start there is a thumping noise coming from the starter area. The starter is a gear reduction installed 4 years ago. The starter has been getting a workout while trying to troubleshoot other issues.

The distributor was installed at top dead center. It is an electronic ignition, 12 volt coil non ballast.
The distributor is tight to the bell housing.
Tight to the bell housing? I don't understand.

The thumping noise seems to be occurring a regular intervals. New clutch was installed 3 years ago and there was little wear to the timing gear.
I don't understand that either. The timing gears and chain are at the front of the engine, not the clutch end.


When did the starter last work correctly? What has been done since that time? What electronic distributor did you install? When you say the thumping happens at regular intervals do you mean it continues to "thump-thump-thump" as long as the key is held in the start position? Have you checked the battery voltage? What are/were the other issues you were working to resolve? I know... it's many questions.
 
It could be a lot of things, thump thump thump, it is Crank ng (engine is spinning on starter) but not firing (starting or trying to start). One guess, distributor is at too dead center, there are two TDCs, one for exhaust stroke, one for power or ignition, I think if you had the ignition on the exhaust stroke you might get a thump, thump, thump.
 
Tight to the bell housing means the starter is not loose and causing the thumping noise. TDC was set on the compression stroke first cylinder. Timing gear was a mis-statement. I meant ring gear.
The noise is not there if I remove the distributor cap.
 
Thanks for the replies. I reinstalled the distributor and the thumping is gone. On the initial install I had trouble lining up the drive gear and drive dog. I lifted the drive gear to ensure it properly seated and I'm guessing I messed up the timing when I did that.
 
Thanks for clearing that up. What threw me off is you said the distributor was tight to the bell housing... not the starter was tight to the bellhousing.

Do you need any guidance on setting the timing now that the dizzy is back in correctly?
 
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