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Discussion Starter #1
My 67 289 usually starts fine if I set the choke first. If I don't, like when its warm, it bucks or shakes like it kicks back and seems rather violent. Recently it pulled the nipple off the PB check valve and has scored the fan shroud. Could it be that the timing is advanced too far or is it a symptom of another problem? It does not knock or ping on regular and pulls 17" vacuum.

A fool is one who having lost sight of his goal, redoubles his effort.
67 Coupe and 99 GT Coupe
 

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So, you're thinking no vacuum leaks....

OK, have you tried cleaning up the idle with the mixture and speed adjustment screws on the carb? If it runs ok with the choke on when cold but not with the choke off when warm, does it run at all with the choke off when cold?...

Also, that's some pretty major movement....have you checked your driver's side motor mount for elastomer separation?...

Check a couple things and get back to us with more details...*G*

Edited to add....I understand your major complaint is during cranking but how does the engine idle?....that's what I meant above. My engine sometimes makes funny noises and hesitates during a hot re-start on a hot day...pre-ignition at work in a heat soaked combustion chamber....

Pat
http://albums.photopoint.com/j/View?u=1570936&a=11937754&p=42910787.jpg<P ID="edit"><FONT SIZE=-1>Edited by camachinist on 03/21/01 08:51 PM (server time).</FONT></P>
 
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No vacuum leaks. It only does it on cranking and then right at first. Further cranking ...no problem. It runs fine otherwise, throttle resonse is good, smooth acceleration, good idle considering the cam, everything is fine except if I don't set the choke, it bucks when the starter is first engagaed. It has a Pertronics but it has never caused a problem. Its like it wants to crank backwards then after the initial kick, cranks fine. I set the timing by vacuum and trial and error since when set by the mark, the advance is too insufficient. While it runs great, could the timing be too advanced for it to start smoothly after sitting for a while? Thanks for your interest. Your knowledge is well respected here.

A fool is one who having lost sight of his goal, redoubles his effort.
67 Coupe and 99 GT Coupe
 

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Yes, it is possible, if your initial timing is too advanced and the engine is hot, that the engine will pre-ignite the fuel while the starter is still bringing the piston to TDC and kick back or stop while cranking...

That is what I was describing on my D-coder but this condition only occurs on hot days after the engine has been shut off hot and heat soaks for a short time, say 10 minutes or so....after starting, I note the engine temp is way over near the hot side but drops as the water circulates....

If the car sets for an hour or so, it starts normally, just like when cold...

Try retarding your timing a small amount, after marking the distributor so you can return it to its previous setting....

Post back about what you find...

Pat
http://albums.photopoint.com/j/View?u=1570936&a=11937754&p=42910787.jpg
 
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