First I will say I've been reading for hours on here about injector/injector cup replacement. I've learned a lot and will repair myself. Still things are still bothering me.. What I have is an lb7 with 320k miles. I first noticed raw fuel from exhaust. I figure stuck/broke injector. Next it began loading up at idle and producing steam. Coolant in combustion chamber or after it. I loose a pint a day now and smoke the road out with a white cloud when I take off. That's what makes me think it's an injector cup. No coolant leaks anywhere on motor I cleaned and looked for way longer than I should have. The truck runs fine with no missing or any issues. Also when parked it loads at least one cylinder with coolant as it try's to lock when cranking. I guess the worn rings allow it to go ahead and crank.. Any way I would appreciate any thoughts from y'all on this issue. Thanks
Lb7 drinking coolant
- Thread starter tommywalton1974
- Start date
That sounds like a head gasket problem. Do you have any coolant in your oil? It will look like chocolate milk if you do
You have a blown head gasket and id get on it fast yours sounds worse then any ive heard of.While your doing the head pull all the cups anyways and do new orings and seals and reloctite them back in.Id quit driving it if it were me untill you can get the parts together IMO
Water in oil at all that's what is strange. I guess if it's a head gasket the location of the leak could be away from the oil passage. I'm tearing it down today. I'm putting all 8 injectors In and have been looking at so cal diesel standard flow Bosch. Any suggestions on injector type?
Also just now when I cranked it it cranked normal and had very little smoke. Also no excessive pressure in cooling system and no air bubble in tank
yeah. Definitely sounds like a head gasket problem. LB7s and LLYs had crimped hgs that were prone to fail. I have a friend that is working on his now replacing the head gaskets and wound up having to do some head work as well. replace the head gaskets and while your at it, put on some ARP head studs.
I will bet one of your pistons will be shiny clean in one spot when you remove the heads. Antifreeze and water does that.
Holy crap my list just got long. It also has a leaking rear main I've been putting off and will do it now. My next question is should I just pull the engine. I have a twin post lift in my shop to make removing the trams much easier for rear main install but with all I now face it may be easier to do this on a stand. I learn by doing and have never done major work on dmax yet. What would you guys do? Btw it's 4x4 also
Either pull the motor or pull the cab
My friend pulled off his doghouse and was ok for doing the hgs, but if you have to replace a rear main seal, I would pull the motor I think and really make life easier while replacing the parts.
Thanks guys. Yep I got it on the lift today the motor is coming out tomorrow. Check this out, I've never seen this before it's a first for me.. The head gasket is blown for sure because I watched water ooz out from the OUTSIDE of the motor. It's coming from the rear corner by number 8. I've never seen a head gasket do that. I hope the head is not damaged. I've seen turbo gas motors eject molten aluminum across the heads mating surface. I'm going back with studs this time. Any suggestions on head gasket?
Darryl and Henry have a deal on the gm gaskets and arp head studs,dont use anything else and probably want to use "c" gaskets
The rear of the cylinder head seem to be the common place they leak, if they leak externally as well.