1985 Bronco....Need help

[Mike Meese]

I wasn't able to interpret "going crazy" in the initial post, but as Yardape said, the backfiring sounds like timing and from the sound of it your timing gear and/or chain may be suspect. My first thought when I read the initial post was timing chain jumping teeth on the sprocket.
If running crazy meant it went red line, then I would suspect something in the linkage so the butterfly/s were wide open.

Good luck,

>-

How do I check timing if I can not start it?

 

[shift1313]

ive had the roll pin shear off in my distributor a few times on my 85. The way it works(on the 4.9l) is oil pressure goes up through the dist shaft i think. Dont know the cause but it hasnt happened in awhile. But if you pull your distributor cap off and you can rotate the rotor by hand, its not connected to the motor anymore. If thats fine(i think i said this above) make sure you distributor itself isnt loose. There is a single bolt and a hold down that lets you rotate it to advance or ****** your ignition timing. Its possible that if it came loose you could be extremely advanced.

To check your timing on a non running vehicle you have to get your #1 cyl to TDC. they make gauges to do this that go in your spark plug hole but you can shine a light(or stick something in the spark plug hole and get it close. Also keep in mind you have tdc #1 on compression stroke and exhaust stroke.

anyways when your at tdc compression stroke your rotor button on the dist should point to the #1 plug wire spot on your dist. cap.

 

[crazyhorse85]

Like shift1313 was saying you want to bring #1 cyl.up on tdc...easy way is pull coil wire off and take plug out in #1...then have a helper bump the switch and you hold your thumb over plug hole and when you reach tdc the pressure will push you thumb off....that should put you real close...pull your cap off the dizzy and see where sit should be pointing dead on #1....If not then you'll have to raise your dizzy up and adjust it.... B)