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cant figure out whats wrong? HELP

tompdog7

Jr. Member
Joined
Nov 29, 2004
Messages
53
i have a 73 eb with a 302. for the last 2 months it has not been running right. it will fire up and run good for about 10 minutes and then it will start acting like it is not getting enough fuel and will die. when it does this the engine temp is 190-200. i have replaced the fuel filter, fuel line, fuel pump, carberator, air filter, coil and resister plate, and rewired the engine harness. it is very frustrating to say the least. i am beginning to think it is overheating and possibly vaporlocking?? i an getting the radiator checked out monday. if anybody has any suggestions please let me know. i think it is related to overheating because once it cools off it will start and run fine for a while. thanks
 

broncow72

Village Idiot
Joined
Jun 5, 2005
Messages
2,174
Loc.
Spring,TX.
Sounds like vapor lock to me. I had the same problem with my RV. I bought an "el cheapo" electric fuel pump and mounted it close to the fuel tank. Instantly cured the problem.
You can wire it from a switched source that will come on automatically or you can have it hooked to a seperate switch that only you know about and use that as a theft preventative.
 

oldiron

Bronco Guru
Joined
Jul 21, 2005
Messages
1,027
look for a vacuum leak

Vacuum leaks can cause the symptoms you describe. i.e. when the engine is cold or not up to temperature yet and the choke is still closed or partly open the vacuum leak is not that big a problem since the engine is using less air through the carb, when the choke opens fully it's too much extra air which will cause a lean condition. Best of luck
Greg
 
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tompdog7

Jr. Member
Joined
Nov 29, 2004
Messages
53
i just started it with the hood up. it ran for about ten minutes. it got to about 190 and i closed the hood. it started running like crap and eventually died. i felt the fuel line and it was very hot from the fuel pump to the carb. when i turned it on without starting it the pump sounded like it was pumping air (vaporlock) and it was extremely hot. the pump it attached next to the engine. i am wondering if that is causing my problem. is 190 too hot. i am wondering if the radiator is causing the problem or if the fuel pump getting too hot is causing it. the temp was 230 when i just checked it i guess because it isnt running and no water is flowing to cool it off?? any help would be appreciated.
 

Sac '68 sport

Bronco Guru
Joined
Apr 9, 2004
Messages
1,176
Loc.
Orangevale
I was getting vapor lock, turned out to be the gas cap. Replaced it and all was good. Try testing with the cap off?
Carb spacer can help too.
 

Scott M

Full Member
Joined
Feb 22, 2005
Messages
285
Loc.
Baltimore
might not be it

but i had very similar symptoms a few months ago. ran great, take it down the road, and after 5-10 miles, start dying. let it sit, and she'd start again.

anyways, i kept thinking vapor lock. had even changed fuel filter recently. ultimately, it turned out to be the filter (well actually rust in the tank, clogging the filter super quick). the pump just couldn't keep up b/c the filter was so clogged, but it would take awhile to starve out.

anyways, granted my 69 sat for like 5 years prior to this, but it clogged a filter in probably 20 miles. i know you said you put in a new filter, but its worth pulling it and blowing in the "out" side to see whta comes out.
 
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tompdog7

Jr. Member
Joined
Nov 29, 2004
Messages
53
i think it is my electric fuel pump. it gets so hot after 10 min that i cant even touch it. it has to be a 12v pump. i dont know what could be getting it so hot. the ground is on the valve cover and could be the problem.
 

Skiddy

Bronco Guru
Joined
Oct 8, 2003
Messages
11,545
Sounds like your pump is getting too hot. I would move your pump closer to the tank away from the heat. Electric pumps are more of a pusher type pump than a puller and will overheat.
 
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