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Discussion Starter #41
Pull the glow plugs and check for compression first,the crankshaft is fine because the belt is turning.
Ok. I do not have a gauge for that. I'll start looking.

I did pull the "new" Reman'd starter I bought. Here's a photo of the FLywheel, or Ring Gear as it were. I also took some photos of the starter. This is after about 40 cranks. Just for a look. The GM OE starter should arrive tomorrow. I'll feel better about having that in at any rate.
 

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It’s not the starter.you don’t need a gauge.pull the glow plugs and have someone crank it while you put your finger over each hole.if it won’t blow your finger off it’s not got compression.
 

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Discussion Starter #43
It’s not the starter.you don’t need a gauge.pull the glow plugs and have someone crank it while you put your finger over each hole.if it won’t blow your finger off it’s not got compression.
Oh sweet. Yeah so I did that early on Saturday. Actually pulled one at a time and held a piece of paper in front of it to see if any "junk" fired out. All of them blew a good enough mist of air out to blow the paper out of my fingertips. I don't know if it was "enough" compression but it was fairly violent.
 

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You need to put your finger firmly over the hole and crank it.it should blow your finger off.like you shouldn’t be able to hold it in the hole.
 

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Discussion Starter #45
It’s not the starter.you don’t need a gauge.pull the glow plugs and have someone crank it while you put your finger over each hole.if it won’t blow your finger off it’s not got compression.
So I just had time for the first one (far left on passenger side facing) and yes: it blew my thumb off the hole for the first few secods. But def not holding compression.
 

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That’s a broken camshaft gear no compression issue if I ever heard one.pull your glow plugs and check for compression.im not sure the exact issue but I can tell there is no compression.are you low on coolant or coolant In the oil?

Just does not sound right does it? Maybe sheared cam pin? None of this is anything that typically just happens out of the blue though. Now say if it began as a loss of prime and then a shot of ether ran it away briefly colliding pistons with valves it would fit.
 
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I think you may be in to it.that would explain the fuel pump having pressure.broken down in the cam gets my vote.
 
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I’m not a diesel genius, but I know my way around a motor. I wrench all my own vehicles, 04 LB7, 2012 LML, and 87 Turbo Regal. I thought the same as Kennedy and sideswiped that your cam is not spinning early on. The thing I DON’T understand about that though is the first couple of seconds you can here some compression, but then it stops. I think there’s a disconnect between the crank and the cam. The only way to know for sure Without digging in the motor is to check compression. You can usually “borrow” one from O’Reilly or auto zone. For now I’m going with my gut and saying the cam is not spinning (or jumped time somehow). Disclaimer - I’m not a pro. Just want to recommend really cheap attempts at figuring out your problem. Edit - also see if you can get a socket on the crank pulley bolt and turn it by hand. The motor should NOT turn over easy with 18.5:1 compression ratio. I think you’ll know.
 

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Discussion Starter #49
F*ck it. This pile is going to the shop.
 
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I have been there before too!! Good luck and keep us posted. I’m anxious to hear the ending.
 

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Discussion Starter #51
I've just gone in a d out of absolutely everything I can I have now exhausted my time, available tools, and I'm about to lose my mind.

Time for my first vehicle to the shop experience. I hope it's a good one.
 

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Discussion Starter #52
I’m not a diesel genius, but I know my way around a motor. I wrench all my own vehicles, 04 LB7, 2012 LML, and 87 Turbo Regal. I thought the same as Kennedy and sideswiped that your cam is not spinning early on. The thing I DON’T understand about that though is the first couple of seconds you can here some compression, but then it stops. I think there’s a disconnect between the crank and the cam. The only way to know for sure Without digging in the motor is to check compression. You can usually “borrow” one from O’Reilly or auto zone. For now I’m going with my gut and saying the cam is not spinning (or jumped time somehow). Disclaimer - I’m not a pro. Just want to recommend really cheap attempts at figuring out your problem. Edit - also see if you can get a socket on the crank pulley bolt and turn it by hand. The motor should NOT turn over easy with 18.5:1 compression ratio. I think you’ll know.
I did turn it over (not easily) to check teeth in the ring gear early in. I just can't spend another day in the driveway pissing and moaning, haha.
 

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Any updates?
 

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Discussion Starter #54
Any updates?
No, I did get everything fully primed, turn the Kennedy lift pump back on, and swapped the shity new starter out for the AC Delco. Things sounded much better, not as gritty and grind e, but still no start. Can't get into the shop until Monday morning so I might tinker around over the weekend but to be honest, we'll probably just let it sit.
 

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Discussion Starter #55
Yeah. So I don't like this, haha. I'll give you an update when I hear back. Hopefully tomorrow.
 

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I had gotten used to seeing my 2012 like that (only on a trailer behind my 2004). Glad I don't have to worry about that anymore! I really hope your only problem is being low on blinker fluid. Good luck.
 

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Discussion Starter #57
I had gotten used to seeing my 2012 like that (only on a trailer behind my 2004). Glad I don't have to worry about that anymore! I really hope your only problem is being low on blinker fluid. Good luck.
Oh no!!!! I just remembered I never checked that! Boy, thanks for nothing guys! Haha.

I am still holding out hope 4 either a quick, or not expensive, or both diagnosis. I'm not convinced on a major mechanical failure given that there was no indication while under a load. It happened overnight, though maybe I should check my security camera from that night to make sure no one was in my driveway with a wrench, hammer, or jug of gasoline while I was sleeping (it was a short sleep too... I was loading the camper till 2 a.m., back up at 6 to finish up).
 

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Hey any update yet?
 

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Maybe get a helper to spin it over while you video the fan/belt spinning so we can get a better handle on what it sounds like with a decent starter in place. It should spin quick, smooth, and even with a steady cadence as each piston comes up. If you know anybody with a LB7 maybe have a listen to how theirs spins.
 
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