1986 GW starter solenoid, relay and key switch so far

[1986 GW Blk JCP]

Hello all,

I have a mostly stock 1986 GW with 360/auto. the other day the key was left on overnight and was dead in the morning. when jump starting it it wouldn't start (i wasn't there).

The starter would engage with the key in the on position (not pushed to start position).

I then replaced the starter solenoid, the ignition key switch and the starter relay and still has constant power to Both front terminals on solenoid with ignition in second position (on). The gauges come up when key is in on position and oddly, I have power to both (+) and (-) coil terminals which is why it wont start even when i jump power to the (S) terminal on the solenoid.

When i try and use the key to start it with all the wires on the solenoid on correctly the starter engages w key in start (it doesn't start) but the starter doesn't disengage by letting go of key OR turning key OFF, so i have to run around and shut starter of by removing battery cable.

I'm thinkin' maybe replace the ign. module and alternator in case there is any backfeed through the two of them. I guess i'll bring a starter too.

...to make things worse, i don't have easy access to the truck as its an island vehicle that requires me to bring parts and tools with me on my MC and its about an hour from an island (limited supply) parts store so most parts have to come with me. any other ideas would be appreciated. thanks!

[babywag]

Could have multiple issues and "new" parts are frequently junk these days.

The solenoid is probably bad either right out of the box, or trying to start it with issue(s) could have welded the contact together again.
Battery needs to be fully charged, starter good, cables good, or very easy to kill a "new" Cheapnese solenoid.

The key on until battery went dead can kill a module.
Having voltage @ both terminals of coil doesn't necessarily mean it is bad.
Did you check for spark?

If the wires on solenoid are reversed I believe will cause the starter to run/engage with key in on position. But it has been many years since I've had a vehicle with that style system so maybe incorrect.

Honestly throwing a bunch of parts @ it may just cause frustration and introduce additional issues. The aftermarket parts of today are a big roll of the dice.

[1986 GW Blk JCP]

Thanks Babywa!! Yes, some parts are rubbish. I'll start with a new ignition module, then new alternator. I agree, i don't think power to both sides of coil is a faulty coil, but either a backfeed from alternator or the ignition module is toast....but power to both sides of coil w key ON will prevent it from starting.

I think i have little choice other than to bring a bunch of parts with me and install them in order of most likely success. I'll bring another solenoid and a way to bypass neutral safety switch as well.

i think the only way the (S) terminal on solenoid would have constant power (even w key in ON position) is bad key switch or bad ignition module. Thanks again for the help!

[babywag]

No, seeing power on both terminals of coil if you're grounding a multimeter lead isn't an issue/problem.
That is not the correct way to test a coil.

oljeep.com has manuals with diagnostic charts if you need them?

since key was left on primary no start suspect would be a module.

[nograin]

I basically agree with Tony.

Originally Posted by 1986 GW Blk JCP

The starter would engage with the key in the on position (not pushed to start position).
.... the starter relay and still has constant power to Both front terminals on solenoid with ignition in second position (on).

This sure sounds like a short (cross wire) or miswiring..
It even could be in the relay.
Safe way to check. Bring aligator clips for your meter leads.
Disconnect the battery.
Disconnect the starter relay terminals.
Check for continuity between the power feed to the switch (labeled always hot) and the Start lead (bright green in the drawing).
Check when the key is in Off, Start, Run, Accessory.
Should only have continuity in Start. If you find otherwise, start disconnecting and narrowing it down.
If it works as it should, then check the solonoid. S to NSS should have continuity. I may have continuity with the big starter lug (sorry not 100% off the top of head whether its on the relayed power).

...to make things worse, i don't have easy access to the truck as its an island vehicle that requires me to bring parts and tools with me on my MC and its about an hour from an island

There's mechanic I think is on one of the islands that's done some work on SJ electrics. Goes by Al's428 on the racing fuel systems forum. Send me a PM or e-mail if you want me to find out more and get contact info.

[1986 GW Blk JCP]

Thanks all! great help and the wiring diagrams were also very helpful. It was the electronic ignition module. When i took the old (not that old) one out it was entirely melted on the back side. I have to start carrying a spare....

thanks!