1977 bronco

[Heredoggydoggy]

Sounds like a faulty emergency brake light switch.  It's too old to have an ABS system.  The Chiltons Manual I have for the Ranger/Bronco II series has electrical diagrams for all the years.  A guy at NAPA printed me out a diagram of a system that wasn't in the book.  Keep it up, and you'll be an expert on those things! 

[bhawley76]

That light goes to your proportioning valve, if it come's on and then goes off its doing what is suppose to.

[Maverick]

Proportioning valve? It's suppose to be on when the key is off and not even in the ignition? Like I said I'll turn the key on and the light goes off.

[Heredoggydoggy]

That might be it..  The Brake system is hot all the time, and the ignition switch might bypass it. Run it for a while--Sometimes when a vehicle is idle for a while, the electrical contacts gum up, and work good once they are used again... If after a month or so, if they still act up, then start trouble-shooting. 

[huntnphool]

If after a month or so, if they still act up, then start trouble-shooting. 

It will be easy to tell after a month because your rig won't start anymore and need a new battery.

[Heredoggydoggy]

If after a month or so, if they still act up, then start trouble-shooting. 

It will be easy to tell after a month because your rig won't start anymore and need a new battery.

Depends on the battery--the instructions that came with my CB radio advised hooking it up to a switched circuit, so it wouldn't get left on and drain your battery.  I inadvertently left it on for a week, and my Bronco II started right up!    Sounds like he is only connecting the battery to run it, though.  Some vehicles develop a "Dark Load", and the battery runs down overnight, and those can be hard to locate! 

[Humptulips]

Brings back memories. First vehicle I ever owned was a 69 Bronco. Traded it off for a brand new 76 Bronco. Often wish I would have kept it but not sure where I would have stashed it.

I rescued so many people stuck in the snow while running my trapline. It seemed like it would go anywhere. I even towed out a family riding snowmobiles that were stuck and couldn't make it back out to the plowed road.

[Maverick]

Put a new fuel pump on it. Blew through the lines and they're clear. But not hearing bubbles in the gas tank. With half a tank we should hear bubbles when blowing through the lines. So tomorrow we'll drop the tanks which we really should have done before anyways and see if the pickup tube in the tanks is rotted off.. At least the fuel lines aren't plugged..

[gonehuntin68]

I am far from a ford guy but man I love those old broncos.     

[hiway_99]

Are you sure you have the fuel tank selector in the right position?  Its on the right side under the drivers side seat.  Check all your fuel lines there probably cracked and sucking air.

Sent from my RM-860_nam_usa_100 using Tapatalk

[huntnphool]

If after a month or so, if they still act up, then start trouble-shooting. 

It will be easy to tell after a month because your rig won't start anymore and need a new battery.

Depends on the battery--the instructions that came with my CB radio advised hooking it up to a switched circuit, so it wouldn't get left on and drain your battery.  I inadvertently left it on for a week, and my Bronco II started right up!    Sounds like he is only connecting the battery to run it, though.  Some vehicles develop a "Dark Load", and the battery runs down overnight, and those can be hard to locate! 

In this case, with it turning on when the ignition is turned off its almost certainly being swithced with a relay. Most relays will draw a few amps of current, which would drain a battery in short order if not disconnected when not in use, which will become a PITA eventually. Best to just track down the problem.

[Heredoggydoggy]

Put a new fuel pump on it. Blew through the lines and they're clear. But not hearing bubbles in the gas tank. With half a tank we should hear bubbles when blowing through the lines. So tomorrow we'll drop the tanks which we really should have done before anyways and see if the pickup tube in the tanks is rotted off.. At least the fuel lines aren't plugged..

Yup.  A vehicle that old, and sitting unused for a while, they might be. I changed all the belts and hoses on my '86 Ranger, too.  They looked good, but that old, you never know.  They were all mostly the originals.  I had to take just about everything off the front of the engine to replace the valve cover gaskets anyway.  I learned with my '91 Ranger that leaking valve cover gaskets eventually kills the starter.

[Maverick]

Yeah so we'll drop at least one tank tonight and see what's going on. Battery is unhooked unless we're trying to start it. I'll worry about the brake light after this thing is running. Once I get running good I'll start fixing up the interior and exterior, exhaust, lift kit and new tires. Already have new wheels for it. Can anyone recommend a lift kit? Can't make up my mind on if I want to run 33s or 35s. Not going to be a wheeling rig. Mostly one I'll cruise around in and maybe take up to the mountains for hunting.

[Skyvalhunter]

So does yours have a 3 on the tree or is it an automatic?

[Heredoggydoggy]

   One word of advice for dropping fuel tanks I learned the hard way:  Make sure you siphon ALL the gas out of the tank.  even 3 gallons makes the tank really heavy!