Hey guys, I've got a buddy with an 02 lb7 that's our work truck. When I started working with him he was loosening the cap on his coolant take everytime he shut her down so it wouldn't hold pressure and leak into his cylinder. I pulled the glow plugs and pressurized the system and sure enough the number 6 cylinder was full of coolant. Radiator hose doesn't stay hard, so I was leaning toward a cup. Especially since it was only the one cylinder and he said it started right after he had his injectors replaced. So I tore it down and pulled the cup, no cracks or anything, but to be safe I cleaned the bore out spotless and used red loctite gel and a brand new cup and o rings. Bolted injector back in right away, then let it sit 24 hrs before adding coolant. Ran great. Better than it ever had he said. Then the 4th day after he ran it for a few hours while it was real hot out and the next morning hard start and white smoke. Burning coolant like crazy. So I tore it back down and did it all again, but used red hi temp loctite and another new cup. Waited 36 hours, rand great for 4 days, ran it long one day and then it did it again. Hard start and eating coolant. It's gotta be the cup since I replaced it and it stopped both times, but how after a long day of running is it making the cups leak? Bad head? Any ideas please. Thanks guys.
LB7: 02 lb7 coolant leaking in cylinder, replaced cups twice.
- Thread starter RBritton
- Start date
Sounds like you know what your doing.
Did you use a new copper washer under injector.
Also I've read need to over torque some times. Maybe another 10 lbs. on the inj.
Could also be a cracked head maybe.
Did you use a new copper washer under injector.
Also I've read need to over torque some times. Maybe another 10 lbs. on the inj.
Could also be a cracked head maybe.
Anything is possible. Cracked hold down also. I changed head gaskets for a bad water that wasn't leaking externally
Any other ideas? I'm thinking either a cracked head in the cup bore or a bad hold down bolt. The head would make sense since the loc tite fills the crack and holds it together for a few days until the loc tite eventually gives. That's why it runs for a few days perfect then back to eating coolant. If it were a head gasket I would think it'd leak no matter what. Right track?