M818 won’t turn over

[Dagostini87]

I bought a 1971 Amgen 5 ton m818 that the previous owner said it ran when he parked it. My buddy and I went and picked it up on his flatbed trailer(we had to pull it on with a winch).
I got it home and put new batteries in it and it won’t turn over. My dad worked for Cummins for 20 years and he came and looked at it and tried to get it to turn over with no luck. We pulled the injectors out and the cylinders look clean, no rust. We poured atf on top of the pistons to try to get the engine freed up and still no luck. We pulled the pan off the motor and everything in the bottom end looks fine too.
Has anybody experienced anything like this on these trucks? thanks for the help!

 

[dmetalmiki]

Why did you not inspect or try the motor before purchase?
Anyway, Why not 'Tug it' gently in a reasonably high gear and high range and see if it is indeed free,
WITH the injectors REMOVED,

 

[tobyS]

If you have the pan off, seems a bar could be used to make it move...or not.

 

[Karl kostman]

I really feel that you need to give it a pull with the injectors out like was mentioned earlier whatever you need to do to see if the engine is actually froze? Right now by the way your describing what you have done it could be a stuck starter?

 

[Tow4]

You can bar the engine over at the accessory drive pulley. I forget the socket size but it's easy to do.

 

[Dagostini87]

You can bar the engine over at the accessory drive pulley. I forget the socket size but it's easy to do.

Thanks for all the input guys. I got the truck super cheap so running or not it was a good deal. I have a large breaker bar on the accessory pully and it doesn’t move by hand. I’ve tried rocking the truck back and forth with my tractor with no luck. I like the starter idea, maybe something in there is hung up.
thanks guys

 

[fuzzytoaster]

I've been there and it turned out that an exhaust valve was open allowing moisture into cylinder #3 causing it to be stuck. It was in a M929 so I couldn't pull start it but in your case lube the cylinders again and give her a pull then drop that clutch. Being a tractor you may not have enough weight on the rear to keep it from skidding but with repeated attempts something will give. If that something isn't the piston breaking free then it wasn't going to start anyway and take out 250's aren't that expensive. Keep us posted!!

 

[Dagostini87]

I've been there and it turned out that an exhaust valve was open allowing moisture into cylinder #3 causing it to be stuck. It was in a M929 so I couldn't pull start it but in your case lube the cylinders again and give her a pull then drop that clutch. Being a tractor you may not have enough weight on the rear to keep it from skidding but with repeated attempts something will give. If that something isn't the piston breaking free then it wasn't going to start anyway and take out 250's aren't that expensive. Keep us posted!!

Thank you! I’m gonna use a little bigger tractor today and see if that works

 

[tobyS]

Something will give....eventually.

 

[Dagostini87]

Something will give....eventually.

Haha yep! Good or bad!

 

[Dagostini87]

Drug the truck forward and back for about 20 minutes today to try to get it to break loose with no luck. Pulled the starter off and still nothing.
scratching our heads for sure

 

[WillWagner]

Cut the filter open and see what is in the pleats. Could have a locked up trans. Roll under it and see if you can use a bar through one of the holes in the flywheel housing on the flywheel teeth.

 

[Dagostini87]

Cut the filter open and see what is in the pleats. Could have a locked up trans. Roll under it and see if you can use a bar through one of the holes in the flywheel housing on the flywheel teeth.

the truck rolls with clutch in or in neutral but the engine won’t turn over when truck is in neutral when we try to bar it over

 

[fuzzytoaster]

Time to drop the oil pan and see what's going on in there.

 

[WillWagner]

Time to drop the oil pan and see what's going on in there.

Think he said he has already done that. If the truck moves with the clutch depressed or in neutral, no issue behind the engine. Cut the filter open to see if there is any debris. Could be a compressor.

 

[fuzzytoaster]

Think he said he has already done that. If the truck moves with the clutch depressed or in neutral, no issue behind the engine. Cut the filter open to see if there is any debris. Could be a compressor.

You're right, he did. I'm curious to the cause as I have a C7 with the same issue and never found the cause.

 

[tobyS]

I watched a show about rebuilding a motorcycle and a mouse had filled the cylinder with nut shells. Locked it up fairly tight. If you didn't find a problem with the pan off....probably time to take off the head(s).

 

[Dagostini87]

I watched a show about rebuilding a motorcycle and a mouse had filled the cylinder with nut shells. Locked it up fairly tight. If you didn't find a problem with the pan off....probably time to take off the head(s).

Yea we were able to look into the cylinders with a bore scope through the injector holes everything looked clean

 

[Dagostini87]

Think he said he has already done that. If the truck moves with the clutch depressed or in neutral, no issue behind the engine. Cut the filter open to see if there is any debris. Could be a compressor.

We were thinking it could be the compressor also, we took the top of the compressor off and it looked clean in there no rust. We may have to dig into the compressor a little farther