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Old 02-09-2020, 04:13 PM   #1 (permalink)
thetundrawolf
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Hi,

I just got new head gaskets on my truck, I started it after install, of course hard starting for a long time but it fired up and ran and idled very well. But this morning I went to start it again, activated the glow plugs for about 10 seconds, and it hesitated a little bit like the last few seconds of cranking last night (after having the system completely open). It didn't start as hard, maybe 4 seconds of cranking (usually starts instantly).

I am also observing some small bubbles in the return line that connects the low pressure side back to the injector Pump, I installed a clear line for it so I can see. Where might the bubbles be coming from?

I should add that I installed all new return fuel lines so the system should be sealed.

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Old 02-09-2020, 07:57 PM   #2 (permalink)
Bigboytoys
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You have an air leak some where IP and back.

Yes new return line seal weepy leaks but won’t cause air into the fuel system pre IP as it’s a pretty much gravity return to the tank.

We can walk you through finding this leak many ways but step one is go over every line and connection, clamp and tighten them, looks for any wet spots of fuel as fuel out, is air in pre IP.

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Old 02-09-2020, 11:28 PM   #3 (permalink)
thetundrawolf
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Originally Posted by Bigboytoys View Post
You have an air leak some where IP and back.

Yes new return line seal weepy leaks but won’t cause air into the fuel system pre IP as it’s a pretty much gravity return to the tank.

We can walk you through finding this leak many ways but step one is go over every line and connection, clamp and tighten them, looks for any wet spots of fuel as fuel out, is air in pre IP.
Okay, I checked all the connections, I didn't see any fuel. But when I went to start it again, it started hard and there was zero fuel in the return line going into the IP. Someone suggested a leaky injector draining into the cylinder, because this was going on when I was driving it last, are the injectors hard to rebuild or at least re seal? I can't afford 200 dollars right now for a new set...
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Old 02-09-2020, 11:36 PM   #4 (permalink)
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Here is some info on rebuilding the injectors.
The pics no longer work but the info is there:
https://www.dieselplace.com/forum/71...-pictures.html
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Old 02-10-2020, 01:01 AM   #5 (permalink)
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Quote:
Originally Posted by OkDually View Post
Here is some info on rebuilding the injectors.
The pics no longer work but the info is there:
https://www.dieselplace.com/forum/71...-pictures.html

Thank you so much!

Is there any way I can pinpoint the specific Injector that is leaking?
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Old 02-10-2020, 09:38 AM   #6 (permalink)
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Quote:
Originally Posted by thetundrawolf View Post
Thank you so much!

Is there any way I can pinpoint the specific Injector that is leaking?
Pull the injectors and pop test them to find any issues.
You can build a pop tester with a bottle jack if you are handy enough.
There are videos on Youtube on how to build one
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1996 K3500 6.5L,( "F" Eng #141 cast block) 5 speed manual, crewcab, dually longbed: 208,000mi.
Diamond Eye 4" Turbo Back Exhaust w/2.5" Flo-Pro Crossover
AirDog II DF165 w/ tank sock delete - XDP
TD-Max boost controller - Kennedy Diesel
OPS extension hose - Leroy Diesel
Glow Plug Harness- PT Wiring Solutions
Glowshift Maxtow EGT,Boost, Fuel gauges
Boost & Fuel Pressure Bolts - Leroy Diesel
2/0 Battery Cable Upgrade - PT Wiring Solutions
PMD w/#9 resistor and Re-Location Kit, mounted to bumper - Leroy Diesel
GM-5 Turbocharger
4.10 gear ratio
OptiLube Winter Formula


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Old 02-10-2020, 12:40 PM   #7 (permalink)
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Quote:
Originally Posted by OkDually View Post
Quote:
Originally Posted by thetundrawolf View Post
Thank you so much!

Is there any way I can pinpoint the specific Injector that is leaking?
Pull the injectors and pop test them to find any issues.
You can build a pop tester with a bottle jack if you are handy enough.
There are videos on Youtube on how to build one

I might do that. Thank you. What are the threads on the injectors where the high pressure line connects to it?

Also, hear me out. Could I discover the leaky one by attaching clear tubing and filling it with diesel fuel on a barbed adapter screwed to the injectors, and elevate the tubing, with a sort of "U" so dust doesn't get in, like a p trap? And when the diesel drains overnight, I will know which injector is leaking? But for like $10?
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Old 02-10-2020, 01:36 PM   #8 (permalink)
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https://mrotools.com/tu-15-13a-lang-...motometer.aspx

I need something like this that I can connect clear vinyl tubing to to see which one is leaking. I am on a pretty tight budget and trying to keep my business going right now... Need this truck to work and stay reliable. My theory is that I can fill the tubing with diesel from a turkey injector, and mark the level, and by the next morning or even over the course of a few hours, I can see if any of the injectors are "leaking", and then I can address that injector specifically. I read you could use crocus cloth or fine sand paper to help the injector "seal" internally, that way I am not buying 8 rebuilt injectors for $200, i can get the truck back on the road for like $20.
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Old 02-11-2020, 12:59 AM   #9 (permalink)
thetundrawolf
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I used a broken injector line and secured some vinyl tubing to it and filled it with some diesel fuel. I marked the level and will check it again tomorrow.
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Old 02-11-2020, 01:52 PM   #10 (permalink)
legendman
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I would think you would be able to find the bad injector if when you pull it, it is wet with Diesel.

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