Starter solenoid help

Stock FSJ Tech Area
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Topic author
J20Hunter1
Posts: 103
Joined: Fri Dec 04, 2020 10:59 am
Location: Central ILL

Starter solenoid help

Post by J20Hunter1 »

I have a 1977 Wag it has an Hei dist factory voltage regulator.I just noticed starter solenoid Red wire with white trace wire is no hooked up ,but it is running fine. My question is will this hurt anything? Thanks for all your help.
Dennis Ridgeway 1977 Wagoneer 360/auto , 1969 J3000 Gladiator , 1983 J20 360 /auto <1978 Cj 5 Golden Eagle

will e
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Re: Starter solenoid help

Post by will e »

I assume the wire that is not hooked up would normally be connected to the small terminal that is closest to the starter motor side of the solenoid. If this assumption is correct you are fine.

Originally your truck had an external resistor wire for the coil. This resistor wire drops the voltage to the coil while running. The problem is it also dropped the voltage while cranking and when you are cranking there is a large voltage drop from the power being consumed to turn the motor over. The small terminal on the solenoid was connected to the coil. It is not a resistor wire. When cranking this terminal is energized and provides power to the coil. Once cranking has stopped, this terminal is no longer energized from the solenoid and power to the coil is provided through the resistor wire.

The HEI doesn't require a resistor wire. So you are fine.
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge
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tgreese
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Location: Medford MA USA

Re: Starter solenoid help

Post by tgreese »

What Will says is basically correct. However, I looked at the wiring diagram for a '77 and there is no red wire with trace (stripe) on a '77.

Sorry, I am now going into the weeds.

To the OP, you're sure this is a '77? What you describe is like the harness from a '78 or later. Possible someone has replaced the '77 harness with parts of a later harness, or the Jeep is not really a '77.

A '77 came with the Prestolite BDI system from the factory. This has no resistance wire. The ignition module (ECU) operates on a full battery voltage all the time. The module controls the coil current for starting and running via the negative coil terminal (green wire to the module).

The original solenoid has no connection for that red/trace wire. The original solenoid is different from what you can get from the aftermarket now, with only one small terminal ("S" terminal) and no second small terminal that provides the ignition bypass ("I" terminal) used on later Duraspark-equipped Jeeps (and many Fords).

A '77 should not have that extra red/trace wire. Compare the '77 diagram to the '78 diagram on the Tom COllins site: https://oljeep.com/gw/elec/GW_wiring.html What the OP describes is clearly '78 or newer.

Regarding the HEI, I suspect the OP has used the coil positive lead to power the HEI distributor. If this is a '77 harness, that will be fine, since the coil primary is at battery voltage whenever the key is on. If it's a newer harness, there is a resistance wire between the ignition switch and the coil. That will probably work but it's not ideal. Better to take power for the HEI from the power wire that normally would go to the original ignition module (ECU).
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

Topic author
J20Hunter1
Posts: 103
Joined: Fri Dec 04, 2020 10:59 am
Location: Central ILL

Re: Starter solenoid help

Post by J20Hunter1 »

It is a 1977 Grand Wagoneer but I have found some of the wiring looks like a 78 . Hard to tell PO spliced some wires.I did run 12 volts to HEI correct with help from some of you guys.I think we are good Thanks for the info again you guys are a lot of help!!
Dennis Ridgeway 1977 Wagoneer 360/auto , 1969 J3000 Gladiator , 1983 J20 360 /auto <1978 Cj 5 Golden Eagle
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tgreese
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Re: Starter solenoid help

Post by tgreese »

Seems like you are ok then.

What color is your Wagoneer? I have a '77 J10 that is Sand Tan.

Pardon me for picking nits. There was no "Grand" Wagoneer until 1984. Prior to that, there was only the Wagoneer. I belive Jeep started using the "Grand" Wagoneer name in '84 because they offered the XJ Cherokee as the "Wagoneer" that year. 4 doors, and faux wood paneling. Don't know what else separated the XJ-platrform "Wagoneer" from the rest, but they took the name for the smaller Jeep and promoted the full-size to "Grand" Wagoneer. Sorry, just nit picking. Here we all know what a '77 Wagoneer is.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

Topic author
J20Hunter1
Posts: 103
Joined: Fri Dec 04, 2020 10:59 am
Location: Central ILL

Re: Starter solenoid help

Post by J20Hunter1 »

Red with red interior
Dennis Ridgeway 1977 Wagoneer 360/auto , 1969 J3000 Gladiator , 1983 J20 360 /auto <1978 Cj 5 Golden Eagle

will e
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Joined: Sat Aug 18, 2012 8:21 am

Re: Starter solenoid help

Post by will e »

Thanks Tgreese, I didn't dig into the weeds of the wiring diagrams. I also learned something ! So that's a win.
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge

candymancan
Posts: 3652
Joined: Tue Mar 22, 2016 11:32 pm

Re: Starter solenoid help

Post by candymancan »

Jeep really was weird for names.

You had a SJ cherokee.. two door and 4 door.. why is a 4 door named a cherokee.. when 4 doors were wagoneers ?

Then you got the XJ wagoneer.. then the XJ cherokee ?? Then you have the SJ Grand Wagoneer. And the ZJ Now Grand Cherokees..from 93 were Grand Wagoneers for the highest end trim for 93 only
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
J20Hunter1
Posts: 103
Joined: Fri Dec 04, 2020 10:59 am
Location: Central ILL

Re: Starter solenoid help

Post by J20Hunter1 »

Sorry about that on the Grand ,You are not nit picking just giving knowledge
Dennis Ridgeway 1977 Wagoneer 360/auto , 1969 J3000 Gladiator , 1983 J20 360 /auto <1978 Cj 5 Golden Eagle
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