75 Bronco - Won't start - Please Help!

[ark75bronco]

I have a 75 Bronco that was passed down from my dad. He had the motor and tranny rebuilt a few years ago. Very recently it started to back fire really bad...Now it won't start at all. He doesn't think it has jumped time.

This is what i've replaced so far:

Ignition Box
Fuel Filter
Checked the Fuel Pump
Carb was junk...Had it rebuilt.

When I poor gas in the top of the Carb to get it started it will start to fire but only long enought to burn off the fuel i poured in.

Any help would greatly be appreciated.

 

[Krayzie]

Fuel pump might have went out on you

 

[TBS-POPS]

When I poor gas in the top of the Carb to get it started it will start to fire but only long enought to burn off the fuel i poured in.

.

Then the carb is not getting fuel from the tank. check all the lines for cracked hoses. cracked hoses will let the pump suck air instead of fuel.

 

[beernut]

If you have a tank selector switch make sure it is still functioning also.

How did you check the fuel pump?

 

[bluebronco69]

definitely sounds fuel related,
i would stop throwing money on new parts for now until you track down the problem.
inspect all fuel lines, if in doubt replace.
check for kinked/restricted hoses as well.

 

[El Kabong]

I use an old lawnmower gas tank with fresh gas & some rubber fuel line to test at that point. I put the tank on the roof of the truck, or tied on a ladder if I'm worried about the paint, so gravity will feed gas to the carb. I run the line from the fuel pump into a container on the ground, so if it pumps gas it doesn't spray all over & set my truck on fire. With that setup all of the fuel system is bypassed up to the carb, & you can quickly tell if everything else is working.

If it runs ok with the gravity feed setup, I do the happy dance while watching to see if the pump is filling the container. If it pumps to the container, it may be just bad gas in the tank that is the cause.

If it doesn't pump to the container, I can connect the lawnmower tank so the fuel pump pumps directly from it to the container. If that works, I reconnect the pump to the carb & see if it runs off of the pump. If it runs at that point, I start looking to a clogged inline filter, a hole allowing air into the fuel line, a clogged pickup in the tank, & so on.

There are probably more direct methods, but it is always a good feeling when the engine fires from the gravity feed tank & you know the rest is ok. I actually use it when I question the tank or the fuel, or for the first fire with a new engine prior to connecting all the fuel lines.

 

[ark75bronco]

Thanks everyone...I pulled the fuel filter and pumped the gas...It was pumping gas thru the hose/filter.

I will try all of your suggestions.