Glow plugs half work

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Subourbon

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82 6.2 diesel, suburban k20

Diesels needs glow plugs to go (GPs).

I did a fuel job, injectors, injector lines return lines etc. Bleeding and it wants to go but it just won't.
I didn't touch the GP system when doing this just pulled out the plugs to assist in bleeding.

It won't starts lotsa smoke bla bla bla.
I did a resistance test on GPs 7 of 8 are good. The 1 bad one is on driver side.
I accidentally pulled one of the wires that connect to GPs loose on driver side, so I redid the ancient and probably original connection with a crimp connector and heat shrink.
Tested, 12 volts

Passenger side, no volts... so I redid that connector too same as driver side.

Interestingly, the driver side connection has the GP relay wire, a wire off the GP controller and another one haven't traced it, all twisted together and part of the connection. I dunno when I redo connections I put whatever was there back where it was with a fresh connection.

The passenger side however only has the big wire coming GP relay. Then tees off into the 4 GPs. Nothing else.

Here's my problem now. I get voltage on both sides. But no amperage on passenger side.

I tested the GPs with jumper cables and battery, clamp on body of GP, grounded to battery, hot wire to positive and touch the connector end with other side of jumper cables. 7 of 8 get hot. Great. Same thing, instead using the trucks harness. So clamp to GP body, ground to negative, and now trucks connector on the GP, turn key, solenoid (or relay) kicks on. And she's hot. But only on driver side. Not passenger.

I jumped a wire (badly) from driver side GP connectors to passenger side to test GP again, with jumper cable set up.
She got hot. Not as hot as driver side but like I said, it was a ghetto jump set up, lotsa of losses
Regardless.

Issue is I'm getting amperage to one side of my GP harness. And I dunno how. Or why. Or what the fix is. There's a weak link somewhere... possibly when I redid connection? Is there a broken wire
But a broken wire wouldn't allow voltage through? What causes voltages present but no amperage.

Is my relay tired? And it only feeds driver side because the relay is bolted on driver side fender? And it less distance for it to travel, path of least resistance n all...

I suck at electrical so any help is appreciated.

Also, when bleeding n trying to start numerous times I had a charger in my batteries to get them full n help cranking. Can does mess around with electrical components???

Cheers, I appreciate any help... I should add i have the old style pin controller screwed into block, changed in 2022.
 

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Strick

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Spray some WD-40 down that Detroit's throat...plenty of it. Give it a chaser of carb or brake cleaner as the GP's do their thing. It should fire up after a couple of these cycles. It's kinda like "one bourbon, one scotch & one beer" by George & the Destroyers!
 

Subourbon

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@Strick , believe me buddy I sat on that starter until the bolts literally actually came loose. And I had to go there and make sure the teeth on the starter were ok.
Brake Kleen WD40. Its tryna fire on 4 glow plugs and it just will not do it it shakes and rattles n smokes. I've been working on this issue since before the was snow on the ground. First it was fuel n stuff. But now this electrical gremlin is killing me
 

Subourbon

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My crimp connection on passenger side wasn't the best so I'm redoing it. I cleaned the GP relay studs for voltage in and out. Traced the controller wiring. It appears I'm not missing anything for passenger side.

I'm sorta betting on the bad crimp connection being the cause. The wire looks ok. It was in a plastic harness protector thing. I inspected the wires going to the 4 GPs. They look alright, no breaks or exposed copper.
I have a spare car for the moment, so it fine. And I'm sure I can jump and connect the driver side harness to the passenger side, but that's so sketchy. I'd rather figure out why I'm getting voltage n no amperage.

So done warming up in the house. Back out we go.
Otherwise, whatre my options here? Get a new, 12 gauge 10 gauge wire? And run from the relay to the passenger side?
Cheers
 

Ricko1966

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Spray some WD-40 down that Detroit's throat...plenty of it. Give it a chaser of carb or brake cleaner as the GP's do their thing. It should fire up after a couple of these cycles. It's kinda like "one bourbon, one scotch & one beer" by George & the Destroyers!
Don't burn brake clean it creates phosgene gas,not all brake cleaners do but,just don't burn any and there won't be accidents. Don't clean parts your going to weld with it either. This has been a public service announcement. Now on to the diesel not starting,cheaper than wd40 and works good for me is kerosene in a plant misting bottle.
 

Old Guy Bill

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I’m not familiar with that diesel setup but…
Could it have a fusible link in the wiring?
 

Subourbon

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@Ricko1966 , I was desperate and I figured if brake kleen won't do it nothing will.
Bit truth be told the truck is bled. It just needs glow plugs to start. IDIs hate not having glow plugs
 

Subourbon

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@Old Guy Bill
Yes there are fusible link on the outlet of the solenoid (relay) but they both seem ok. I don't know how to test them they're like a thicker part of wire wrapped in black rubber bout an inch long. Unless I'm mistaken.
I read that when they go, you should be able to pull the wire out, and I've tried and it's tight. Also, any break in the system I'd have no voltage.

I redid my crimp connection. No difference. Voltage present but no amperage. Plugs ice cold.
 

Subourbon

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Oh never mind. Now there's no voltage or amperage on passenger side. Just dandy. Something is real screwy. I'm gonna triple check the fusible link again
 

Blue Ox

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It's been a while, but my recollection is that there's fusible link and connections all through the harness. So you may have to unwrap the whole thing and go through every bit of it.

The black rubber cylinder is the connection, the fusible link is the wire itself.

I wouldn't be squirting brakekleen of any flavor into it. The chlorinated stuff doesn't burn, and the solvent stuff is probably too volatile for a glowplug engine. If you disable the glowplug system you can try using starting aids, but I would avoid it if you're not experienced.
 

Subourbon

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I don't like using any starting aids. Ether, brake kleen, magic.
I was desperate just hear it chug.
I didn't know GPs were that crucial to ots starting.. I had it plugged in. Battery booster. Treated her nice etc etc...

And it's now started.
I dunno about stock but. The pink n blue wire that tell the solenoid to click. And the 2 big wires coming out to go to each Individual bank of GP... well they go I to this black connector. Why? I dunno.
But I took that apart, and the crud man. It was nasty.
Cleaned that up. Set up my jumper cables expecting not different result. Well, I'll be. She glowed. Glued. Glowedidided.
Put everything back in, turn key and oh man what a sweet sound.

Its a death trap coz 2 injectors are bubbling and leaking on the exhaust manifold but that's small peanuts compared to what I spent the last 3 weeks trying to figure out. Snug er a lil nd that's that.

So moral of the story I guess... check your connections? Simplest answer is often the easiest? I dunno. I couldn't be happier right now.
The soot though. Ewww... all that unburnt fuel just puked out the exhaust.
 

Subourbon

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@Ricko1966 , interesting read.... I think I'll forward it to my buddy whi likes spraying brake kleen on welds as they're happening lol.
 

Ricko1966

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@Ricko1966 , interesting read.... I think I'll forward it to my buddy whi likes spraying brake kleen on welds as they're happening lol.
It's not all brake cleaners,I just make it a personal habit to not heat any,so there isn't a chance of a mistake someday.
 

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