Hey guys,

I just purchased a 1986 F-150 4x4. It has the 300 motor, 4spd toploader transmission. The previous owner rebuilt the motor and it is pretty fresh. I bought this truck as a basket case. Needed a transfer case, and various other things to put it on the road. I have completed building the truck and it is ready for the road. It starts and runs but not really well.
The intake manifold is an Offenhauser and it has a 2bbl. Motorcract carburetor. No EGR and no air pump. The coil is aftermarket and sits on the drivers side fender well. The distributor is the one that has the ignition module mounted to it. I think this is the wrong dristributor for my application.
The problem I have is, the timing is jumping all over the place. I checked it with a timing light and it is not steady at idle or at high RPM's. The truck starts and runs but it has timing issues. I feel like I need to switch to an older type distributor with a built in advance, either mechanical or vacuum or both. What do I need to look for? What years did this distributor come in? I assume if I get the older type distributor I will need to use the old style ignition module that mounts to the fender well? Duraspark? Am I on the right track?
Did the timing in a 1986 truck get controlled from the computer? If so, this is my problem. I believe the computer is not working or even still in the truck for that matter. There is nothing on this truck anymore that would be computer related.

Any advice would be greatly apreciated.

Roy

 

Sounds like you have it figured out. Just look for a distributor that has a vacuum line connection. You can buy a new one at the store, or just look from the late 70's to the very early 80's for the dist. The module with the blue plastic you can get from any Ford/Mercury product, v8 or 6, from the late 70's to the early 80's.

Also if you have the money, you can buy one of those new fangled HEI dist Fords. I am assuming they make them for 300 sixes, but am not sure. Ebay would probably be the place to look for the best price.

 

Thanks for the information. I want to keep this project cheap so I will do the junkyard route for now.

Thanks for the reply.

 

Check your distributor shaft for play IN ALL DIRECTIONS. I knew a guy whose crew blew an engine because of this. The timing was all over the place. Most directions the shaft was tight, but when he hit the worn area, it wobbled.

 

This may sound really stupid, but it happened to me and at least one other fella here that I heard about. Look at the timing marks on the harmonic balancer. Then slowly turn the motor over by hand inspecting the same surface of the harmonic balancer all the way around. I found another "notch" if you will- for timing the motor. I tried timing by it and it worked. That may explain why the timing is all jumping around on you.

I agree with Franklin 2 about the duraspark ignition set up, I just did mine a couple moths ago myself.

Check out that harmonic balancer and let us know what you find out. I might be wrong, but I could be right.