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Discussion Starter · #1 ·
i have a 502 bbc with tunnel ram and mech fuel pump after running 20 min fuel to the pump is cool but the pump is very hot and fuel line from pump to carbs real hot. fuel in both fuel filters bubbling then no fuel to carbs. why is pump heating fuel. should i just intall a electric pump.
 

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is your fuel line from the tank to pump ran inside or outside the frame rail and what are you using steel/ss/rubber and what size is it?
 

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Discussion Starter · #3 ·
fuel line outside the rail and is steel. fuel line from the tank to the fuel pump is cool but the fuel pump is hot and line from pump to carbs hot
 

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Might need to add a return line fom the carbs to he Tank. Sounds like you are pushing more fuel than you are using and that is creatingresistance which is leading to your hot fuel issue.
 

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i have a 502 bbc with tunnel ram and mech fuel pump after running 20 min fuel to the pump is cool but the pump is very hot and fuel line from pump to carbs real hot. fuel in both fuel filters bubbling then no fuel to carbs. why is pump heating fuel. should i just intall a electric pump.
yep shes boiling fuel<vapor lock> appears u hav lots of heat under hood, and u need to cover fuel line from out let of pump to car.
appears the pump is gettn hot from the block.Never seen that before? .

heres a example what u can use , its by tech flex, they hav different materials also , and also in black too, for fuel lines
as pump, go electric Im running holley black pump electric
 

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Guys, I had similar problems on my 283 (heating and vapor lock) and tried several steps to solve the problem - moved fuel line away from block and insulated it (no go) - installed elect. fuel pump with return line (no go) - fuel lines were already outside the frame so I wrapped headers (no go). One day we had engine running and stuck a hand behind the elect. fan - it is a 16" puller w/shroud stuck on an AFCO aluminum radiator w/AC condenser- the fan was pulling less volume than it really should (2200 - 2500 CFM) and it was blowing a very concentrated stream of hot air right on the carb and filter (the radiator is in the 6 cyl. position). Pulled the elect. fan off and installed an 18" SS fan on the engine and fabricated purpose-built shroud - now there is enough air flow to cool the radiator (doesn't get over 190 in Texas heat) and there is sufficient volume of air in the engine compartment to keep the fuel from boiling. When all else fails, you might try this. AWC
 

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thank you for that info. i will change my fan back to the old 70s style fan that i have.i my 55 i get a tremendous amount of heat from my fan and i think that what causing the vapor lock.fuel pump heats up ,line & carb also heats up to the point of vapor lock.i will post it if thats the problem.thanks again
 

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The coil? So when it died you saw bubbles that meant nothing and assumed vapor lock? (just trying to figgure out how a coild would make the vapor lock - unless you are usig the coil for a fuel filter :sign0020:)
 

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when the car died i look @ fuel filter and it was enpty so i asumed that it was vapor lock.at the same time the coil died,but when it cooled it started right up.i had it running in my garage the last time, temp.went to 160 and it shut off,but this time i had gas. so i checked the elect. and low and behold it was the coil.had it out a couple times and the gas in the fuel filter seems to go to differint levels and it still runs........ go bucks
 

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If I had a buck for everytime I jumped too soon based on one or two symptoms... I would have enough to pay for all the parts I've bought that weren't really needed!

Good deal for ya. However the varying fuel is still problematic - I think you are sucking air somewhere, - as the engine was dieing there was not enough suction to overcome the air intro possibly. Check all your supply side hoses, clamps etc. just to be sure.
 

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been there done that.talked to a guy that has a 57 and the same glass filter and he says his allways runs with with no gas in the glass bowl.well it looks like it doesnt have any gas in there.he said he nevers has any problem.i just cant understand y each car i see that has a glass bowl it differs from car to car bb or sb it doesnt matter.
 

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Discussion Starter · #18 ·
ok well my fuel was bubbling in both glass filters and was so hot i couldnt hold the filters. update. i think ive fixed the problem, the mech fuel pump gave way yesterday stopped working. so i installed an electric pump and a regulater didnt change nothing else, fuel lines are cool again after running 45 min and filters are running 1/2 full all time. im guessing here but must have had a bad pump from the start. i really do thank you all for the replies and the help. i guess this problem with fuel can be many different causes:shakehands:
 

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been there done that.talked to a guy that has a 57 and the same glass filter and he says his allways runs with with no gas in the glass bowl.well it looks like it doesnt have any gas in there.he said he nevers has any problem.i just cant understand y each car i see that has a glass bowl it differs from car to car bb or sb it doesnt matter.
I've seen the same - the only thing I can figger is that when the filter is nice and clean and has very little resistance it doesn't hold any fuel in the cup - some elements have more resitance even when new (based on microns of filtration). I would then think the ones that show nothing in the glass are not as efficient as the ones that do. Just a wag.
 
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