1970 Ford 3000 runs inconsistent

[wheelsanfun]

Hi all, working on the 3000 has been and still is a challenge. At first it would idle a few moments then stall out it would stall flat if you tried to throttle up, fuel pump helped a little, still no real difference, carburetor finally got it to run long enough to check other things but ran ropey. After a friend inadvertently bumped the distributor the engine came to life, so after inspecting it finding it worn and rusted i replaced it. Then the tractor came to life and ran great for a week. it started missing and running ropey again. looked under the tin and found all three spark plug boots popped off of the plugs. put them all back on engine ran great for awhile then one popped off and it all went south again. Since that day it will start and run ropey take some throttle but nothing smooths it out. I replaced the regulator and coil thinking it could lie there. the only thing i've done lately that made any difference is to regap the points and descale the contact pins in the cap. then the motor started at first crack of the key idled smoothly, throttled up smoothly so i decided to try moving it and it went back to running ropey again. does any of this sound at all familiar to anyone and have you been able to locate the gremlin. Thanks

 

[Quebecguy]

I don't know about your Ford but my International of about the same vintage suffers from quickly corroded contacts between the distributor and the spark plug cables and between the coil cable and the distributor. The cure is to apply plenty of dielectric grease to all of these contacts when the cables and cap are new. Good luck!

 

[wheelsanfun]

Thanks, I love that stuff.

 

[wheelsanfun]

externally resisted coil in an internally resisted coil system = burned out condenser. Couldn't read the old coil. until I took it off.

 

[stingray1]

Thanks for letting us know what you found.

 

[Phillip w]

Here are a couple things. How old are your plug wires. Start the tractor in total darkNess and watch the wires. If there is arking between the wires or to the engine, replace the wires. I had an old 345 international pickup like to drove me crazy and one night it was acting up. I raised the hood and bingo. They ark just enough to make it run like crap and yet it will run. Another thing does it run like crap with high humidity or when there is a fresh few? Might try a replacing the distributor cap. Sometimes you can have a crack or other problem and not be able to pick it up with the naked eye. Another thing if you didn't get thinks tight you timing might have slipped. If you don't have a timing light, you can get pretty close timing it by ear. Just real the distributor while it is running and listen to the changes.