77 with fuel problems
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77 with fuel problems
I have a 77 with a 460 in it. 2wd.
I started having what I thought was vapor lock issues awhile back. Seemed to only be on hot days and I could kind of 2 foot through the pause in fuel to the motor. But the truck now will do it as soon as it reaches normal temp it starts to putter and just dies, and will not turn over again without putting some fuel in the carb. I replaced fuel pump and filter and it started on 3rd crank after sitting a couple months. Took it for a test drive and as soon as it reach normal temp puttered and died and now won’t start again as if it has no fuel. New pump and filter, there is in fact gas in the tanks...
any ideas would be appreciated... I’m kind of lost at this point as to where to go next.
I started having what I thought was vapor lock issues awhile back. Seemed to only be on hot days and I could kind of 2 foot through the pause in fuel to the motor. But the truck now will do it as soon as it reaches normal temp it starts to putter and just dies, and will not turn over again without putting some fuel in the carb. I replaced fuel pump and filter and it started on 3rd crank after sitting a couple months. Took it for a test drive and as soon as it reach normal temp puttered and died and now won’t start again as if it has no fuel. New pump and filter, there is in fact gas in the tanks...
any ideas would be appreciated... I’m kind of lost at this point as to where to go next.
Last edited by 4sr77supercab; Aug 2, 2018 at 03:04 PM. Reason: Grammar
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I had a similar problem and it was old rubber fuel lines that had gotten soft. With heat and suction from the pump they got pulled closed and she shut down. I'd suggest inspect and replace all rubber lines unless they are recently replaced.
I assume you have already replaced fuel filters.
A gunked up fuel tank can cause excess suction and symptoms of vapor lock also. Crud on the pickup builds up and combined with warm temperatures she sucks vapor and shuts down.
At one point I rigged a fuel pressure gauge on the feed line to the carb with a "T" and about 12' of rubber hose. I taped it outside the windshield so I could see as I drove. OE and Holly type carbs like 7 psi (say 5-9) and Edelbrock type carbs like 3-5 psi.
I assume you have already replaced fuel filters.
A gunked up fuel tank can cause excess suction and symptoms of vapor lock also. Crud on the pickup builds up and combined with warm temperatures she sucks vapor and shuts down.
At one point I rigged a fuel pressure gauge on the feed line to the carb with a "T" and about 12' of rubber hose. I taped it outside the windshield so I could see as I drove. OE and Holly type carbs like 7 psi (say 5-9) and Edelbrock type carbs like 3-5 psi.
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From: S.E. Louisiana;so far USA
I have a 77 with a 460 in it. 2wd.
I started having what I thought was vapor lock issues awhile back. Seemed to only be on hot days and I could kind of 2 foot through the pause in fuel to the motor. But the truck now will do it as soon as it reaches normal temp it starts to putter and just dies, and will not turn over again without putting some fuel in the carb. I replaced fuel pump and filter and it started on 3rd crank after sitting a couple months. Took it for a test drive and as soon as it reach normal temp puttered and died and now won’t start again as if it has no fuel. New pump and filter, there is in fact gas in the tanks...
any ideas would be appreciated... I’m kind of lost at this point as to where to go next.
I started having what I thought was vapor lock issues awhile back. Seemed to only be on hot days and I could kind of 2 foot through the pause in fuel to the motor. But the truck now will do it as soon as it reaches normal temp it starts to putter and just dies, and will not turn over again without putting some fuel in the carb. I replaced fuel pump and filter and it started on 3rd crank after sitting a couple months. Took it for a test drive and as soon as it reach normal temp puttered and died and now won’t start again as if it has no fuel. New pump and filter, there is in fact gas in the tanks...
any ideas would be appreciated... I’m kind of lost at this point as to where to go next.
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Dents had very robust fuel systems used with 70's spec gas. With current pump gas, not so much. Some do OK if everything is clean and just right and maybe no hot hard use. Many do not.
I like to drive my dent and that means she needs to run OK on whatever pump gas I find... with or without ethanol and no airport gas. Getting the tank and lines in good shape + electric pump gets the job done for me.
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