Thursday I hauled a large trailer load of wood, no problems.
Friday I did the same. The truck was not running right. It acted like it was not getting enough fuel and low on power, and back firing. I am thinking the fuel filter is getting plugged up or the plug wires are damp and it's misfiring.
I got the load of wood and got it delivered and it's running worst, really lacking power and back firing.
I made it within 3 miles of home and it quit. By the time I walked home my daughter had just came home form College for Christmas break with the Suburban. I used it to bring the trailer home (thinking it might not be there the next morning).
By now it was 5PM so I decided to wait to tow the truck home for daylight.
It was 3:30PM before I could get help to tow the truck home. No EASY way to get it into the pole barn, so I had an hour of daylight to work on it. New fuel filter, new air filter, new spark plugs, cleaned cap and rotor. Still no start and out of daylight.
I am thinking the pickup coil in the distributor has failed, or the brain, box or coil.
Next day I tried a spare brain box, still no start. So off to the auto parts store to buy a pickup coil. Not in stock, have to order it. You would think they would have parts for a 36 year old truck So I ordered it for next day deliver.
Picked up the distributor pickup coil and installed it today. Still no start. My next thought is it jumped time. Before I pull everything off the front of the engine. I put a socket on the crank to turn it by hand to see how far of the rotor is from #1 when I get it turned to TDC. When I check it's off by a cylinder and 1/2, meaning it's not pointing at #1, but between the next two terminals on the distributor.
I don't know why, but I grabbed the rotor and tried turning it. And it turned all the way back to #1, almost 1/4 of a turn. Being gear drive from the cam it should not have turned!
I pulled the distributor and found the roll pin for the drive gear sheared. What was left of the roll pin in the shaft had bound up the gear about 80 degrees off.
A new roll pin later, distributor ready to install, but does not want to seat. I hooked up a remote starter button and start turning the engine while tapping the distributor shaft with a rubber mallet. FINALLY it seats.
After everything is reassembled, I try starting it. Fires right up!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! and runs like it's old self.
That was my 4 day weekend. All because a 1/8" x 3/4" roll pin sheared. At least the drive gear did not fall off into the oil pan.