No spark

RANDY YEAGER

MEMBER
1986 FORD F-150
5.0L
V8
2WD
AUTOMATIC
87,000 MILES

I bought this truck listed above and drove it home because it was a 1986 year. I replaced two fuel pumps, a new distributor, coil plugs and wires. It would not start. Ran checks on all wiring to the distributor, all good. Replaced with a new distributor. Again, start and run drove twelve miles then it shut off and will not start. I rechecked all wiring, okay, had new distributor checked out, okay. Now I don't know what or where to look for.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

So, if after replacing the distributor the engine will start and run then we have to assume the issue is contained in the distributor.

https://www.2carpros.com/articles/how-to-check-for-ignition-spark

https://www.2carpros.com/articles/how-to-test-an-ignition-system

What happens a lot of times to these Ford engines is at some point someone replaces the oil pump drive shaft that connects to the bottom of the distributor, and they use one that is too long. This causes the distributor to wobble, and it actually breaks the rotor button or even the distributor itself.

So, I would suggest removing the distributor and making sure the oil pump drive shaft is not bent. Roll it on top and see if it wobbles. It should roll smoothly.

Basically, if this is the issue then we may have to replace the distributor again. However, we need to narrow in on the distributor and find out why this is causing no spark after a short time.

Let's start with making sure this is okay and go from there. Thanks

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