Fuel Pump
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Joined: Jun 2003
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From: Placedo TX
Fuel Pump
Had problems with rust & trash in the gas tank. Replaced with new gas tank & rebuilt Holley Carb.& new Fram Filter. The filter is inbetween the mech.pump & the carb ( it is in the vertical position). It is a see-through filter. It seems that every so often the filter seems to be full of gas but then all of a sudden its almost empty ( while engine is idling) there isn't enough gas for it to even reach the bottom of the filter. When the engine is shut off there isn't any gas in the filter. Is this normal or is the fuel pump going bad? Can this cause an unstable idle?
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Re: Fuel Pump (1quik6)
It is normal. I had one of those on a truck of mine, did the same thing.
They are rather dangerous, the glass can break. If you choose to use one, make sure that it is not riding on any surface and that it is in a safe location.
I use a piece of rubber hose, split down the center to shroud the one I had. I wanted to use it to monitor the crap in the tank.
Mark
They are rather dangerous, the glass can break. If you choose to use one, make sure that it is not riding on any surface and that it is in a safe location.
I use a piece of rubber hose, split down the center to shroud the one I had. I wanted to use it to monitor the crap in the tank.
Mark
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From: Placedo TX
Re: Fuel Pump (ghostrider20)
ghostrider20,
The filter is a plastic fram filter about 1"dia.x 2" long. I take it that the filter doesn't need to be at least 1/2 or full- for proper flow to the carb? Would it cause an unstable idle or make the engine turn off?
The filter is a plastic fram filter about 1"dia.x 2" long. I take it that the filter doesn't need to be at least 1/2 or full- for proper flow to the carb? Would it cause an unstable idle or make the engine turn off?
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Re: Fuel Pump (1quik6)
I don't have the answer to why the filter does not have fuel in it, but I have seen this condition many times in the past and it never seemed to be a problem.
Please note that GM never put a fuel filter with rubber hose connections between the pump and the carb.
I have seen too many engine fires on old carbureted Fords and retrofits when the rubber line ruptured.
I have always recommend a solid line between the carb and pump. I add an inline filter back at the tank where the rubber line exits the tank unit.
Bettter to be safe.
Please note that GM never put a fuel filter with rubber hose connections between the pump and the carb.
I have seen too many engine fires on old carbureted Fords and retrofits when the rubber line ruptured.
I have always recommend a solid line between the carb and pump. I add an inline filter back at the tank where the rubber line exits the tank unit.
Bettter to be safe.
Drifting
Joined: Dec 2002
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From: Long Beach CA
Re: Fuel Pump (1quik6)
I have a similar set-up, an inline filter between a Holley fuel pump and a Holley carb. No the filter, doesn't fill up. Can you be more descriptive about what you mean by an unstable idle? When does the engine cut out -- cruising speed, idle, or?
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From: Placedo TX
Re: Fuel Pump (LB66383)
It seems to cut out after the car warms up to temperature (180 deg.) at idle. Seems the car can't idle less than about 1100rpm. I've taken the dist.apart and cleaned it out & I reset the dual points to 30 deg.dwell at idle. Seems that the dwell is fine- rock steady. Also, when the Air cleaner cover is put on the carb. the engine tends to turn die. If I remove the cover it's fine (it has a new air filter cleaner). It has never acted like this before. I can even take the air filter out & just put the air cleaner assembly on the carb. because it still tends die. When reving the car (in neutral) it seems that the engine tends to hang up & won't return to original idle (900rpm), seems to want to stay at about 1300 rpm. The throttle linkage isn't hanging up & the choke is wired open.- Frustrated.
Team Owner
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From: Washington Michigan
Re: Fuel Pump (1quik6)
What kind of distributor do you have (dual-point distributors weren't used after 1962), and does it have vacuum advance? What kind of carb, and how much clearance do you have from the top of the bowl vent tubes to the installed air cleaner lid if it's a Holley? 
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From: Placedo TX
Re: Fuel Pump (JohnZ)
JohnZ,
I have a dual point Mallory Dist. without vacuum advance. As far as the clearance, the top of the choke butterfly blade seems to be touching the top of the air cleaner. The choke has been wired open. I post this same situation in another topic (Holley carb.). Holley 600cfm. Thanks
I have a dual point Mallory Dist. without vacuum advance. As far as the clearance, the top of the choke butterfly blade seems to be touching the top of the air cleaner. The choke has been wired open. I post this same situation in another topic (Holley carb.). Holley 600cfm. Thanks
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From: Clayton NC
Re: Fuel Pump (1quik6)
You say it idles fine when the air cleaner base is off? You also said that you have a soft line between the filter and the carb... Sounds like you could be crimping you soft line with the air cleaner base when you tighten it down... Dave
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From: Placedo TX
Re: Fuel Pump (youwish2bme)
I just finished swaping out my stock filter assembly with the one off my Pu truck (V8-350) it has a 9" chrome air filter assembly. Well the car seems to be idling fine now. I just can't understand what changed after the carb.rebuild, I watched the guy rebuild the carb. personally. I really would like to keep the stock air cleaner assembly. Any suggestions? I also screwed in the secondary blade screw adjustment on the passenger side all the way in then idled it back down a little with the idle screw. Seems to be running strong again.
