42 replies to this topic

[hamman]

There is a fuel relay sut off that will stop fuel shut off and spark. It is located on the fender also. There is also a engine kill under the dash that is there in case of a crash. Sometimes they go bad. I had the fuel relay go bad on my old 88 F150 with a 300 6 that is setting out back. Replaced it and it worked fine. Hope you can figure it out. Roger. P.S. All the above suggestions are valid and deserve checking out.

[916 hydro]

There is a fuel relay sut off that will stop fuel shut off and spark. It is located on the fender also. There is also a engine kill under the dash that is there in case of a crash. Sometimes they go bad. I had the fuel relay go bad on my old 88 F150 with a 300 6 that is setting out back. Replaced it and it worked fine. Hope you can figure it out. Roger. P.S. All the above suggestions are valid and deserve checking out.

it has a mechanical fuel pump

[916 hydro]

im gonna try switching distributors tomorrow

[LTD]

You need to sell that old Fix Or Repair Daily and buy a Chevy.

[UncleWillie]

If it starts and wont pull it sounds like it is out of time. I would suspect the timing chain. Did you check it for slack? they are really easy to replace.

[Amigatec]

One thing I found once on a 454 Chevy. Is the wires going from the outside of the distributor to the pickup coil had broken inside the insulation. On this motor the only way it would start is if you advanced the timing, and then after it started you could set it back and it would run just fine.

What caused it was every time the vacuum advance, advanced the timing it would bend the wires going to the pickup coil. And finally they had broken.

I like to never have found it.

[chris m]

That is strange that it burnt up another coil. something must be shorting out? I would check the wiring just to be sure.

 

Unless the pick-up in the distributor is shorting out?

 

In any case good luck.

[Alc]

Did the 86s have the ignition module mounted on the side of the distributor  like the 85s ? But I can't remember what the 80s where on the fender in a box ? ,could it be the wrong coil ?

Edited by Alc, June 10, 2013 - 08:10 PM.

[oldedeeres]

Gotta shotgun? Lift the hood, insert gun barrel, pull trigger, close hood, call Willie. Problem solved.

[WNYTractorTinkerer]

You guys sure are a lotta help!  Remember when you were driving the old things??  Old tractors is OK but talk about a truck and you guys rib the heck outta him!      

 

Don't pay no never-mind to the anti-Ford sentiments!  OK Hydro?

 

Yes-  a shorted coil will burn out as GP says..  Positive power to the + terminal and a constant ground connected to the - terminal will cook it quick..  The box should give it intermittent ground 'signals' to make the coil fire as the rotor spins and is located @ the correct plug tower on the rotor.  It's been quite a while since I've worked on one of those (I think I still have a couple V-8 box-distributor combos somewhere)  Root out that problem and find another coil..  Is there a lot of dirt/corrosion inside the distributor?  I've seen bad pickups ore messed up signals coming from the sender as a result as well  (the sender is the doo-hickey thingy under the rotor..)  On TDC of the compression stroke of #1 cylinder the rotor should point towards #1 cylinder..  (Look @ timing marks on cam cover)  Position the distributor so #1 tower is about 8 degrees before the rotor and that should be good enough to get the engine started.  Time it with a light and rock on!!

[Amigatec]

I have found an easy way to check the pickup coil is to unhook from the wiring harness, and set your meter to ohms, spin the distributor either by hand or with the starter, every time the trigger wheel and pickup coil line up, the meter will show a reading.

This works better with a meter that has a needle. As your spinning the distributor the needle should bounce.

EDIT: I meant to say voltage instead of ohms.

Edited by Amigatec, June 11, 2013 - 09:25 AM.

[DougT]

I have found an easy way to check the pickup coil is to unhook from the wiring harness, and set your meter to ohms, spin the distributor either by hand or with the starter, every time the trigger wheel and pickup coil line up, the meter will show a reading.

This works better with a meter that has a needle. As your spinning the distributor the needle should bounce.

The ohm setting is for checking the resistance. When you spin the distributor the pickup coil is producing an ac voltage signal. Ohm meters don't tolerate voltage well. The reason the needle jumps is because its twitching from being shocked. Try it on the ac volt scale and you should get somewhere around 1/2 volt ac. I've never seen a pick up coil cause the coil to short and burn out. Take a good look at the harness.

I didn't think the 300 has a chain, I think they are gear to gear.

[Amigatec]

I'm sorry I meant to say voltage. Instead of ohms.

[chris m]

The ohm setting is for checking the resistance. When you spin the distributor the pickup coil is producing an ac voltage signal. Ohm meters don't tolerate voltage well. The reason the needle jumps is because its twitching from being shocked. Try it on the ac volt scale and you should get somewhere around 1/2 volt ac. I've never seen a pick up coil cause the coil to short and burn out. Take a good look at the harness.

I didn't think the 300 has a chain, I think they are gear to gear.

Yes they are gear to gear no chain. They are very easy to replace also, I don't even think it took an hour from start to finish to do mine.