Hey guys my lb7 motor locked up on me on the highway. No warning lights all gauges showed good. Went to pass a semi and it wouldn't idle back down. Before I could get to the shoulder it shut down. Let it sit for a bit then it cranked 5-6 times and locked up. I thought it hydrolocked but I took out glow plugs and tried to turn it by hand to no avail. I have it taken apart to the heads and I don't see anything obvious to me. I don't know a lot about diesel motors. Wondering if anyone might have an idea of what to do first?
LB7: Need help
- Thread starter Jmwindham
- Start date
Have you tryed hand turning it by the balancer? Maybe transfer case? Did you try rescaning for codes?
Not neccesarily. It will only lock up the drivetrain if something seizes connected to the output shaft. If something seizes connected to the input, it can stop the engine but still rotate at the output shaft.
Crank bust? Threw a rod? Drop a piston squirter into the crank? Broken flexplate?
Need to go further into engine teardown unfortunately...
Need to go further into engine teardown unfortunately...
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Pull the starter and you can get to the bolts through the starter hole. Not to likely to be the transmission though..
Unfortunately if he cant turn the engine over he won't be able to remove those bolts.
What you can do is pull the transmission leaving the converter attached to the engine. The transmission will need to be slid straight back until free of the converter before you can drop it
Metal could have lodged in the converter if it came apart inside. Or if the pump broke, it can make a real mess. I seen once where the converter got froze into the front of the trans, and they couldn't get the engine and trans apart because of it. They ended up having to torch the flexplate to break them apart.
I doubt it's the tranny cause unless pump or converter seized, it would still move. And your description of what happened doesn't really match that. Going with bent rod some bottom end failure. But either way, gonna need to pull tranny first to even get at it. Unless you can pull engine trans together.
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My truck broke a tooth on the tranny pump gear and the converter spun on the two flats and locked everything up. So it is possible.
Ya I’d try rolling the engine both directions from the balancer bolt. If she’s locked up pull the trans with converter still attached to the engine. Then you will know which end piled up. My guess is it’s the engine but I’ve heard of weird things locking the trans up as mentioned above.
Thanks everyone for the help. I am still in the process of finding the problem. I will remove transmission and see that helps anything. I have almost got it ready to pull engine bit did not want to risk messing up my transmission. Will pulling the transmission first prevent any damage to it?