77' 3B ENDTB 675 won't turn over acts like it's siezed

[Mtnmblmech]

Howdy-

I am trying to help the old boy next door get his dump truck running again and having some issues. The truck ran great for him and then all of a sudden it just died. He restarted it again and it ran for about twenty minutes and then died again. I asked him if his oil pressure was low when that happened and he said when he first started it, it was only pumping at twenty some psi. The engine now will not turn over now and is acting like its seized. I unplugged the jake to make sure it was not possibly creating and issue upon start up. It has new batteries and starter seems to be engaging fine. Just wondering how I should I go about testing without completely dismantling, other possible causes of this symptom (I was thinking injection pump gear issue or valve train/timing problem). I am a busy man but would really like to help the my neighbor out as it provides him with much needed income and he is just one of those awesome old guys that deserves to have someone else help him out for once. Please help and thank you for your time.

[tkobes43]

I'm sure someone will chime in to help you... But welcome to BMT!

[rhasler]

See if you can turn the engine over using a wrench on front crank hub bolt (the big bolt in the center), turn clockwise.

[joes mack]

cut open the oil filters to see if there is any metal in them.. joe

[Mtnmblmech]

Turning the engine over by hand was next on my list to try, going to do that tomorrow. Will cut filters if it does not turn over. Appreciate the help very much and thank you.

[41chevy]

If it doesn't turn over by the wrench and no metal in the oil filters.Did it smoke at all? White or black smoke? Check for low coolant in rad or coolant in the oil. If it is low, I personally would look towards coolant in one of the cylinders causing Hydro lock. Paul

[Mtnmblmech]

I asked him if it smoked before it died and he said it didn't and never really has ever smoked. I thought it may have have been locked when I first looked at it so I pull #1,3,&6 injectors to help release compression, and tried to turn over and got nothing. Will try turning over by hand tomorrow and go from there. Appreciate the help and thank you very much.