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Discussion Starter #1
Ok this what I have, 351C 4V Road demon Carb C6
When I set the timing right on it starts and runs ok, but if I floor it and kick in the passing gear, I get, back fire back fire back fire,If i anvace the timing it is real hard to start, Barely turns over, Weak battery? Every now and again I get a plume of white smoke out of the Pass. side exhaust. this is when I slow down. But not every time. I am assuming a blown head gasket between the water chamber and Cylinder. It wasn't doing this this last fall, this just started. The water inlet by the thermostat is leaking badly I have to replace it, could water from there be getting in through the base of the distributer? The coolant settles right there.
If you guy's or gals Could give me an idea what to do that would be helpful.

Just when you get one thing fix something else goes.
I guess thats why we love this hobby, right?

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73 351C C6 3.25 T-lock
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Mustang's are just a Hobby
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If you advance your initial timing too far it will be hard for the starter to turn it over.

The backfire sounds like its going way lean when you get into the secondaries or it could be that your advance isn't advancing. I hope you didn't just slap that carb on there without doing your jet work.

Water smoke from a head gasket going away will usually be worse when you are rev'ing the motor up. I've had a head crack do what you described. It would close up and then open up for a while until it finally broke loose completely.



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So much for the test drive....

backfires where? out of carb or exhaust....? can you duplicate this with the trans in neutral ?

Does the engine cold start OK after setting all night?

Get your coolant external leak fixed and keep an eye on the level...if it starts disappearing, do a dye test of the coolant for exhaust gases...

Can you duplicate the smoking problem by revving the engine up in neutral and closing the throttle?

When do we start having fun here?? *G*

Pat
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Discussion Starter #4
No, I can't make Smoke while in Neutral.
Yes iturns over fine after sitting all night. It is after it get warms up that it cranks slow. This is just with a little advanced timeing not a lot. I did Just what the video that came with the road demon said to do to prep it before installation. The road demon has fourcorner metering and say's to set all four the same, could I be too lean on the secondaries? could this be causing the backfireing. I beleive it is back firing through the carb.

http://albums.photopoint.com/j/View?u=1603896&a=12227373&p=44503083.jpg
73 351C C6 3.25 T-lock
Jesus is all the world to me!
Mustang's are just a Hobby
http://www.folksite.com/TFOB
 

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Ok....I'll assume you've checked for water in the oil...

Personally, I don't think you have a blown head gasket or cracked head...you'd be overtemping when you get on it because of combustion gases getting into the coolant...

How does the PCV hook up on your car?

Your Road Demon is likely fine...I'll assume you've done all the routine things like check float levels, idle screw function and the like...
Your idle circuits, even if totally blocked, wouldn't be causing backfires at WOT...it would just idle lousy...

If you do have a coolant leak by the distributor, you might be getting some high voltage shorts, which may be causing your backfires...

Re: the smoke....have a friend drive behind you while you duplicate the problem, if possible...have he or she smell the smoke and describe it to you...might be oil or coolant...oil can burn real light sometimes too...

How's your oil consumption?

Details, details...*G*

Pat
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Discussion Starter #6
YA Pat no over temping going on. The PCV hooks right into the Intake manifold in the back behind the carb. there is like a triple Vac fitting where it hooks in


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73 351C C6 3.25 T-lock
Jesus is all the world to me!
Mustang's are just a Hobby
http://www.folksite.com/TFOB
 

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where is the distributor vacuum advance hooked up?

If you have it hooked to a manifold vacuum source instead of a ported vacuum, when you floor it, the vacuum drops, the timing goes way retarded, and the engine will backfire, hesitate or even die.



Jack Collins
1966 Mustang Coupe
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Discussion Starter #8
Dis. vacuum is connected to the ported vac connection on the demon carb

http://albums.photopoint.com/j/View?u=1603896&a=12227373&p=44503083.jpg
73 351C C6 3.25 T-lock
Jesus is all the world to me!
Mustang's are just a Hobby
http://www.folksite.com/TFOB
 
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