73fj40 no spark

[bigbird73fj40]

Hello…new to this FJ40. It’s been running well but has has intermittent issues with it going dead at stop sign and no sign of life when I turn the key. It’s probably happend a few times but then all of sudden it fires up.
Pulled into garage other night and next morning it turned over but wouldn’t start.
Checked fuel and we are getting that
Spark plugs are all new but no spark.
Fuses seem to be all good. Doesn’t seem like the distributor is getting power. It’s a HEI performance distributor. Could it be a bad ignition switch and not sending power to distributor? Need some help. Thanks

 

[charliemeyer007]

Fuses need to be good and have clean contacts. Check the fuses with a meter - they can look good but actually are bad. Disconnect the battery ground. While fuses are out use a bent 30 cal bore brush to clean the fuse contacts. Clean the battery contacts and use protective spray on both the post and the connector before putting them back on.

Does the starter engage? Yes - use a jumper wire to the dizzy - does it run? yes switch/wire/connector could be bad

 

[ceylonfj40nut]

Likely a bad ignition module in the HEI distributor. Happened to me 2 weeks ago. Looks like this

 

[pb4ugo]

Good call @ceylonfj40nut. It could very well be the problem. They'll start failing when they get hot. Over time they just quit working. They're pretty easy to replace.

 

[JohnnyC]

You should use thermal grease on the module as well … helps with heat… and that’s what kills them

 

[ceylonfj40nut]

^^. They give you a small pouch of it when you buy a reputable ignition coil. Did some research and went with

 

[bigbird73fj40]

Installed a new ignition module but same issue.
New ignition switch coming today so howfullly that’s the problem.

 

[JohnnyC]

you could pull the switch and where the wire connects .... jump the connectors to see it starts... done it on my 74 to figure out if it was bad... it was... took it apart and cleaned and worked ... put a new in anyway... so got a good spare

 

[bigbird73fj40]

New ignition same problem no spark. Ran jumper from battery and started right up. Fuses are all good. Bad ground somewhere?

 

[JohnnyC]

I would say to start tracing the ign wiring

Test light time

You did check the fuse block like mentioned earlier right? Power in and out at the block … make sure fuse is good … sometimes they look good but desoldered

Can’t recall if there was any connectors between… but… could be a culprit… while holding key to start try moving wires under dash to see if it goes

Could be a break in the wire maybe

Coolermans wiring diagram depository:

https://globalsoftware-inc.com/coolerman/fj40/schematics/FJ40/1972-73FJ40/Haynes1973FJ40M.jpg