No start after motor swap

Embarger

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Well during this quarantine I decided I would under take my first stab at a motor swap. The truck is a 96 and the motor is out of a wrecked 97 with 200k. Everything was fairly straight forward and plugged right in. I've topped off all the fluids and filled the fuel bowl and nothing. I think it's something electric, the truck turns over but I'm not seeing any smoke. Won't fire on either either. I checked connections and swapped the cam position and still nothing. Can anyone point me in the direction of what to check next?
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psduser1

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Double, triple check the 42 pin connector on the drivers side head.
Before you crank the engine, check the oil level in the hpop reservoir, it should be about an inch below the top. No oil=no injection event.
Do you have a battery charger hooked up while cranking? Slow cranking or low battery voltage will be a killer also. You should be seeing at least 11.5 volts while cranking, with the charger hooked up.
Are the glow plugs coming on?
 

Embarger

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Glow plugs are working, while im cranking it appears I have oil pressure and there is oil in hpop for sure. Hooked up to trickle charger so I have good cranking amps. I'll recheck the 42 pin connector though.

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psduser1

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A trickle charger may not be enough to keep cranking rpm fast enough, depending on battery or starter condition.
 

psduser1

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How long did your replacement engine sit before you bought it? As in, are the fuel and oil rails filled?
I've had a couple engines that needed a lootttt of cranking for a first fire up, especially higher mileage engines that had been sitting for a while.
 

Embarger

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I'm not sure how long it sat before I got ahold of it. I'm not sure what the voltage is while im cranking but it seems ample. Would the fact it wont fire on either prove that it is in fact an electric issue?

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psduser1

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I'm not sure how long it sat before I got ahold of it. I'm not sure what the voltage is while im cranking but it seems ample. Would the fact it wont fire on either prove that it is in fact an electric issue?

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That would point to a compression issue, in my mind.
Low cranking speed, poor ring sealing, or, possibly, valves not sealing, will not allow enough cylinder pressure to build, resulting in no fire.

Did you see/hear the engine run before you bought it? Need some backstory, lol.

Assuming the engine is in reasonably decent mechanical condition, you only need enough rpm to build cylinder pressure, enough oil to actuate the injector, and cam position sensor to signal the pcm to fire the injector.
Ether eliminates two of those requirements.
 

Embarger

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The motor came out of a truck that got t boned and totaled I purchased it from a friend that runs a wrecking yard he told me the truck had 200k and still ran after the wreck. I'm really at a loss all the connections look good its pushing fuel at the fuel bowl (cracked the bleeder valve while cranking) hpop has oil, shows oil pressure while cranking sounds good while cranking just refuses to fire. I've been told they can be a bear to prime but good god I would think it's primed by now. I have a bit of smoke out of the exhaust but nothing crazy.

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Lt.Dan

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If you're getting smoke out the tailpipe, then the PCM is commanding the injectors to fire. That's a good sign. Usually if you're getting smoke, then it's a glow plug issue, or low compression like mentioned previously.
 

Bgdiesel

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If your getting some smoke then you must be hearing the injectors start to click and inject some fuel, but simple trick to help worn injectors and or low compression is to plug the block heater in and come back in a few hours and give it another shot, not all starting fluid is the same we like the John Deere starting fluid, also engines do seem to loose ring seal or there is some slight buildup on the cylinder walls from us being in the south and by the ocean salt air and high humidity.. but what I am getting at is we have brought many engines back to life that had obvious signs of no compression and just needing and engine rebuild or replacement by mixing bg products brake clean and trans fluid in a sure shot can and using it to start the engine I only reference the brand because they have changed brake clean and from what we have been able to get locally only the bulk brake clean wants to start engines in the past 5 or so years... give it a shot and report back. Bg possibly sells smaller quantities that you might be able to obtain


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superpsd

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Agreed with above I would plug in block heater. Let that sucker warm up. I have got 7.3s fired off that have been sitting without fuel. I disable the glow plugs spray WD40 down it's thoat and very small whiffs of starting fluid. I would actually just start with the WD40 first that and a heated block would probably fire off quickly if your already seeing smoke. WD40 will help bring the compression back up on a engine that has sat.
 
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Lt.Dan

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If you want to pull the glow plugs out too, ive here you can pour a little Mystery Oil (or a lubricant of your choice), to get a good ring seal as well. After sitting for too long, cylinder walls will loose their oily film and it takes a while for rings to seal against them again.
 

Embarger

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I've been out of the state working but I'll be back tomorrow hopefully. I'll give it a shot and see what happens. Thanks fellas for all the good info.

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tomlin

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It sounds compression related. Here's why. You used ether. It should fire on ether without a PCM or any electonics hooked up. If it won't fire on ether, it won't fire on diesel. I would disconnect the glow plug relay or controller and giver her a good snort of ether. If it doesn't fire, you have a major compression issue
 

ghohouston

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I doubt seriously it's compression. I'd clean the area around the i.c.p. sensor, then remove it, and top the oil rail off with a small funnel. You can also pull one of the plugs on the passenger side oil rail and do the same. It likely just needs more cranking. I've seen plenty of motors that have had the fuel system apart not really run on starting fluid, they will sort of hit as long as you're feeding ether to it, but they still wont start. My guess as a professional diesel mechanic of over 10 years is either the fuel system or high pressure oil system is not bled fully, provided everything else is good.

And for the ultimate stupid question, have you re checked the engine oil level?
 
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tomlin

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I will say it again. It needs 3 things to fire. Fuel, air and compression. If you have all three the engine will run with NO electronics or NO oil or IPR or HPOP or PCM. He stated he sprayed ether into the engine. Either he is getting no air, IE blocked plenums or no compression or not enough ether. If you have all three, a diesel will run.
 

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