1986 GW starter solenoid, relay and key switch so far

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Topic author
jcpianka
Posts: 11
Joined: Sun Jun 24, 2018 3:53 am

1986 GW starter solenoid, relay and key switch so far

Post by jcpianka »

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!

SJTD
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Location: Lompoc, Sunland or somewhere between

Re: 1986 GW starter solenoid, relay and key switch so far

Post by SJTD »

So key off, everything's normal. Key on, power to ignition and gauges. Key to start it cranks but no start. Release key and starter still runs...

Sounds like there's a short between the the output of the solenoid to the input that causes it to lock in when it picks up.

Been a while since I messed with a car with points but seems to me that if the points are open the coil should have 12v on both terminals.
Sic friatur crustulum

'84 GW with Nissan SD33T, early Chev NV4500, 300, narrowed Ford reverse 44, narrowed Ford 60, SOA/reversed shackle in fornt, lowered mount/flipped shackle in rear.

Topic author
jcpianka
Posts: 11
Joined: Sun Jun 24, 2018 3:53 am

Re: 1986 GW starter solenoid, relay and key switch so far

Post by jcpianka »

yes, that sounds like a good summary. no points on this one, but coil has a (+) and (-) and both are hot when key is on. Both terminals on solenoid (S) and (I) are hot with key in ON position and when starter engages turning to OFF doesn't shut starter from cranking, Thanks for helping out. This one is a bit odd.

candymancan
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Re: 1986 GW starter solenoid, relay and key switch so far

Post by candymancan »

SJTD wrote:So key off, everything's normal. Key on, power to ignition and gauges. Key to start it cranks but no start. Release key and starter still runs...

Sounds like there's a short between the the output of the solenoid to the input that causes it to lock in when it picks up.

Been a while since I messed with a car with points but seems to me that if the points are open the coil should have 12v on both terminals.

Points is old.. this engine doesnt use points maybe in the early 70s ? . its an electronic ignition controlled by a little computer called an ecm..
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

Topic author
jcpianka
Posts: 11
Joined: Sun Jun 24, 2018 3:53 am

Re: 1986 GW starter solenoid, relay and key switch so far

Post by jcpianka »

yes candymancan you're right. This one has a newer, but stock, distributer....no points. I did upgrade the coil, wires and cap/rotor to HEI (although not distributer) about six months ago to get a little better/more consistent spark. been cold starting and running great since then.

Could leaving key on damage distributor?

Thanks again....still hoping someone has some experience with alternator backfeed or another explanation for what might be going on here.

78 WIDETRAC
Posts: 196
Joined: Mon Mar 25, 2013 9:53 am
Location: Portland, Ore

Re: 1986 GW starter solenoid, relay and key switch so far

Post by 78 WIDETRAC »

I would put money on it having something to do with the resistor wire.
it heats up with the key on. Dig into the engine wiring harness. Start where the harness comes out of the fire wall . That is where the resistor wire starts, and look for melted wires.
That would explain the sudden additional power to both sides of the coil. and the turning over but not starting.
91 Grand Wagoneer
89 Grand Wagoneer
80 Golden Hawk
81 Cherokee

will e
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Re: 1986 GW starter solenoid, relay and key switch so far

Post by will e »

Check for spark. If you have spark, spray a bit of starting fluid or drip some gas into the carb, put the air cleaner back on and see if it runs for a moment. If it runs for a moment, you have a fuel issue.
81 Waggy 'WILL E' Retired
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Topic author
jcpianka
Posts: 11
Joined: Sun Jun 24, 2018 3:53 am

Re: 1986 GW starter solenoid, relay and key switch so far

Post by jcpianka »

Thanks all! Ill check resistor wires (i think there are four to the solenoid)...and yes that would explain it although i was hoping it wasn't in wiring harness.

No spark, which in this case may be good thing because if it started and the starter is still engaged and not shutting of with key in ON position i may not have noticed it. Thanks for the suggestions! I appreciate it

78 WIDETRAC
Posts: 196
Joined: Mon Mar 25, 2013 9:53 am
Location: Portland, Ore

Re: 1986 GW starter solenoid, relay and key switch so far

Post by 78 WIDETRAC »

jcpianka wrote:Thanks all! Ill check resistor wires (i think there are four to the solenoid)...and yes that would explain it although i was hoping it wasn't in wiring harness.

Only one resistor wire. It's unlike the rest of the wires it's solid core. the one's you may be thinking of are fusable links. yes defiantly look at those also.

No spark, which in this case may be good thing because if it started and the starter is still engaged and not shutting of with key in ON position i may not have noticed it. Thanks for the suggestions! I appreciate it
91 Grand Wagoneer
89 Grand Wagoneer
80 Golden Hawk
81 Cherokee
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