Rough Idle
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Rough Idle
I just replaced my motor on my 73 two-wheel drive from a 240 to 302 I also removed the three speed manual trans and installed a c4. The truck idles great in park and runs real smooth down the road. My problem is at stop signs or whenever I stop and the truck is in gear then it knock and shakes real bad it seems to under a major load. I checked the timing at it is right on the rpm in neutral is 700 I am running an edelbrock manifold and four barrel carb. I did install a 2" exhaust system that fits really tight but I don’t think that is the problem I am hoping for few ideas any one out there that help me?
Thanks
Keith
Thanks
Keith
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Joined: Sep 2003
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From: Other side of the sunrise
Vacuum leak would be my suspiscion. Check that manifold for a sensor hole that is leaking or loose/bad base gasket on the carb, Transmission vacuum line,....
Listen for a vacuum leak hiss or wistle. Try the old spray trick around the intake manifold and carb mount....
Listen for a vacuum leak hiss or wistle. Try the old spray trick around the intake manifold and carb mount....
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Joined: Aug 2005
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Pull the vacuum line that goes to the shift modulator on the transmission. If you find ATF in that line then the diaphram is ruptured. This will inject ATF into the vacuum port at the manifold. IF that turns out to NOT be the issue I would install a vacuum gauge on the manifold and route a hose to the cab to watch what happens. Check and verify what your timing is set at. I find that 10 degrees BTDC works well on a 302. If you are running a Ford Duraspark electronic ignition you may look at a faulty set of pickups or spark module.
Cheers
Bill
Cheers
Bill
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UPDATE
I found a hair line crack in the intake manifold which is an edelbrock. I now have a new problem that I will post here and start a new post.
I went to the edelbrock becase my cast manifold was leaking water at the rear of the manifold so I replaced it. What I find now is on the old cast manifold at the rear the water ports are not there to match the head they are blank off no connection from one side to the other maybe that is why I was leaking. The edelbrock has a channel running from one side to the other. Now the and motor and heads are a 302 1978 the cast intake is a 1973. My question will this cast intake work or do I need a new manifold?
Thanks again
Keith
I found a hair line crack in the intake manifold which is an edelbrock. I now have a new problem that I will post here and start a new post.
I went to the edelbrock becase my cast manifold was leaking water at the rear of the manifold so I replaced it. What I find now is on the old cast manifold at the rear the water ports are not there to match the head they are blank off no connection from one side to the other maybe that is why I was leaking. The edelbrock has a channel running from one side to the other. Now the and motor and heads are a 302 1978 the cast intake is a 1973. My question will this cast intake work or do I need a new manifold?
Thanks again
Keith
