M923a2 8.3 Injection Pump Troubleshooting

[Flatlander]

So I won a truck and am awaiting my EUC to clear. I spoke with the site rep and he told me that he cranks the truck, fuel gets to the injection pump, but goes no further. His opinion is that there is a shear pin on the gear that drives the pin that needs replacement. Is this an issue any of you have seen? If it shears, is the IP likely to need replacement?

He said there is a cover that can be removed to visualize the pin. I'm thinking I can do that if needed, and probably can replace the pump if needed. Haven't done it before, but after reading the TM it dosn't look too difficult. I'm a little foggy on the timing procedure, is that difficult?

 

[Flatlander]

Here are some pictures of the pump and the front of the motor.

 

[simp5782]

Have one in NC that actually broke the timing gear on the crankshaft. No way to know until you open it up. Could be a bad pump. timing gear or anything or he may simply not have a clue what hes doing as far as priming it. These are all possible.

 

[MAdams]

Sorry I can't help but there is no shear pin or key on the IP gear. Its a tapered shaft.

 

[Flatlander]

Sorry I can't help but there is no shear pin or key on the IP gear. Its a tapered shaft.

The site rep may have been referring to the timing gear, which drives the IP gear.

 

[Flatlander]

I have just about decided that I should have the truck delivered to a local mechanic rather than to my house. While I know I could remove the front cover and repair a shear key, or even replace the IP, anything more involved would probably be too much for my experience level with these engines. So, I'll shop around and find a reputable place here in Lubbock to work on it. If anyone is aware of a good shop, let me know!

 

[Flatlander]

Have one in NC that actually broke the timing gear on the crankshaft. No way to know until you open it up. Could be a bad pump. timing gear or anything or he may simply not have a clue what hes doing as far as priming it. These are all possible.

What can cause a timing gear to break like that?

 

[simp5782]

What can cause a timing gear to break like that?

This one the cam broke and bent some valves. It spun over and sounded normal as well.

Or it just broke. Things do break for unknown reasons.

Sent from my SM-G935P using Tapatalk

 

[snowtrac nome]

the gear could have came loose and slipped time or a mechanic put one on wrong and didn't time it right I have seen that before also chech shut d0own solenoid and emergency shut off make shure they are in the proper position mw pumps don't have shear pins or key ways the gear must be torqued to 130 ft lbs or they will slip

 

[snowtrac nome]

through out my years in service we had a lot of problems with 8.3's getting air in the system you might try a good bleeding if that fixes it the fun starts looking for the air leak.

 

[Flatlander]

through out my years in service we had a lot of problems with 8.3's getting air in the system you might try a good bleeding if that fixes it the fun starts looking for the air leak.

I'm hoping this is the problem! I'm thinking tracking down and fixing an air leak would be a lot less $$$ than replacing internals...

The site rep told me he was able to get fuel to the IP, but that nothing was getting pumped through. Do you think that would be a pump issue rather than an air in the fuel line issue? I didn't ask him how he knew there was fuel getting to the pump. He's a nice guy and I can call him back to ask him questions if you think there are any that could help with diagnosis.

 

[Cade904]

What did you end up finding on this? I’m currently facing the same issue.