• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

Died on the way home backfire won't start

lonesouth

Contributor
Bronco Guru
Joined
Dec 18, 2003
Messages
5,045
I had been driving all day at varying levels of throttle, all was smooth sailing. On the way home, about to get on the interstate and I heard a loud pop and what I thought was a blown tire smacking the wheel well, and the engine died. I got out and examined things, no blown tire, I decided it was severe backfiring out the tailpipes that I had heard. Now, if I crank it, it will occasionally stumble, but will not run.

I'm thinking the best case is that the distributor somehow jumped a tooth. Does that sound like the best place to start?
 

spap

Contributor
Bronco Guru
Joined
Jan 2, 2010
Messages
2,457
Maybe the timing chain depends how many miles
 
OP
OP
lonesouth

lonesouth

Contributor
Bronco Guru
Joined
Dec 18, 2003
Messages
5,045
Engine is a reman ATK 351w, it has been installed for less than 100 miles.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,833
My guess is the pop is a result, not a cause.

Basics. Fuel, spark, compression, timing.
Carb is easy for fuel check, look down the throat and see if you get an accelerator pump squirt.
Next up would be spark/timing. bump the engine over until you get to TDC #1 on the timing pointer. Pop the cap and look at the rotor, it should be pointing real close to #1 or 180° from it. Either is OK (depends on if on compression or exhaust stroke and really doesn't matter for this). If it is off you have bigger issues, especially with only 100 miles.
Spark is also an easy check. I start with the coil, but don't stop there. I got burned by a bad rotor once where I had great spark off the coil, but none at the plugs cause the rotor burned through to the shaft. So check for spark at a couple of different plugs.

By now you should have found something.
 
OP
OP
lonesouth

lonesouth

Contributor
Bronco Guru
Joined
Dec 18, 2003
Messages
5,045
After reading some and calming down, I did exactly that, start with the basics.

Checked the carb, moved on to the distributor. 351w with explorer accessories, duraspark distributor. I knew the distributor was setup fully clocked one way or the other, so it wasn't obvious right off that it had moved to the other stop. When I checked it, there was a little play, but I was unable to move it more than 1/8", so I didn't think it would have walked. Just for kicks, I loosened it up and moved it the other way. Once the engine had unflooded, it fired up.

Looks like I need to do a little more work on the timing and tuning.
 

miikee73

Shadetree Guru
Joined
Dec 14, 2010
Messages
3,551
Loc.
Aloha
After reading some and calming down, I did exactly that, start with the basics.

Checked the carb, moved on to the distributor. 351w with explorer accessories, duraspark distributor. I knew the distributor was setup fully clocked one way or the other, so it wasn't obvious right off that it had moved to the other stop. When I checked it, there was a little play, but I was unable to move it more than 1/8", so I didn't think it would have walked. Just for kicks, I loosened it up and moved it the other way. Once the engine had unflooded, it fired up.

Looks like I need to do a little more work on the timing and tuning.

I had the same thing happen. Pulling a steep hill in my camper when the dist moved until the vac advance hit the intake. I had bumped the timing a little for the trip and didn't get the dist tight. It blew up both mufflers,3200 rpm when it went.:cry:
 
Top