1969 Chevy Truck

1969 CHEVROLET TRUCK
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CHEVYSSCAMARO
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Transmission problem
1969 Chevy Truck V8 Two Wheel Drive Automatic

Could transmission fluid coming out of the vacuum modulator on a th 350 cause the truck to backfire and die when put into gear? The truck has a 305 in it. The truck was running when I bought it, but had a blown head gasket, before replacing the head gasket, the truck didn't have this problem. While the top half of motor was apart, I replaced the intake manifold with a Edelbrock performer, and put a Edelbrock 600 cfm carb on, and a new distributor cap and rotor. The truck will start and idle with a bit of a miss which causes the motor to jerk, I turned the distributor toward the front of the truck and it seemed to smooth it out a little, but when put in gear it backfires thru the carb, and then dies.

Could it be the vacuum modulator?

Thanks in advance.
Oct 25, 2008 at 12:44 AM
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DOCFIXIT
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Think motor is out of time big time. Assuming engine mechanical sound the backfire through carb means a plug is firing with intake valve open. Get on top dead center check dist rotor location is it just at NO. 1 If not dist needs to be reset. Make sure crank is on 0 and NO. 1 piston is up on compression. Remember dist shaft will rotote 30 deg. when instaled.
Oct 25, 2008 at 3:18 PM
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