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Old 12-05-2009, 06:47 AM   #1
chadvicki
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Engine Problems Need Help Please

I have a 350 SB and was driving on the freeway at about 65mph when the engine started to die then came back then die then came back. I let off the gas for a few seconds and then it was fine for another 30 seconds or so. I exited the freeway and took at look. Nothing looked wrong. In neutral I can rev the engine no problem. But when it is under load it started doing this. I wasn't able to make it home. It started idling at 2,000 rpm's and was very rough.

Here is what has been done to try to fix this so far. The mechanic put a new carb on it. Edelbrock 1405. That did not fix it at all. Took the manifold off to see if the seal was bad. It didn't appear to be bad. Said he is going to put a new seal on. Fuel filter new. Checked timing. Distributer is only 6 months old.

Does anyone know what else could be wrong? Water did leak where the thermostat is a little. Spark plugs and cables are also 3 months old.

Any help is appreciated.

Thanks,

Chad
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Old 12-05-2009, 07:18 AM   #2
mikey531
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Re: Engine Problems Need Help Please

this is way out in left field and have no idea if it could happen, did you check the vacuum line to the transmission?
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Old 12-05-2009, 07:31 AM   #3
jim zag
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Re: Engine Problems Need Help Please

Sounds like It is running out of fuel. Take the line off the carb and hook up a pressure gauge and see how much pressure the pump makes. Should be around 5 or 6 lbs. Then take the gauge off and check the volume by pumping fuel into a container. You should get about a quart in about 15 or 20 seconds. If not replace the fuel pump.
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Old 12-05-2009, 08:24 AM   #4
cdowns
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Re: Engine Problems Need Help Please

its common for the fuel strainer in the tank to plug up with 40years of crap causing a symptom like this

as far as the fuel pump volume is concerned the factory service manual specs are one pint pumped in 30-45seconds
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Last edited by cdowns; 12-05-2009 at 08:32 AM.
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Old 12-05-2009, 08:40 AM   #5
cparman
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Re: Engine Problems Need Help Please

CDOWNS X2. I might add that if the sock in the tank is clogged, you could take shop air with a blow nozzle attached, and blow backwards thru the fuel line that attaches TO the fuel pump. Take the gas cap off before doing this.
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Old 12-05-2009, 10:51 AM   #6
chadvicki
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Re: Engine Problems Need Help Please

I will tell them to try these things today. I also read something about the brakebooster diaphragm could be bad and to disconnect it and see if that works.

Thanks for the good leads.
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Old 12-05-2009, 11:15 AM   #7
piecesparts
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Re: Engine Problems Need Help Please

Just a thought---along with t he fuel check change out the coil and check the distributor cap and rotor for nasty buildup on the contacts.
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Old 12-05-2009, 02:22 PM   #8
tim21391
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Re: Engine Problems Need Help Please

if your still running points in your distributor.. id change that and i betcha thats the problem.. thats what it was in mine
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