Cat C7 Shutting off

Have a CAT C7 in a 2006 Freightliner M2. First thing first this truck takes a beating. It is used to spread lime and fertilizer in fields and I have rode with the guy in it and he has it in second gear running wide open all day long. Turning 2500 rpms non stop and the engine stays at 200+ coolant temps. Here is the problem. It is shutting off. When it shuts off sometimes it will not start back up. It was serviced recently so it has fresh oil and filter. The injection pump and injectors were replaced about 8 months ago along with rear check valve and injection sensor. It has a code for injection pressure and during startup it is only putting out 500 psi. I know this is not enough. It will not start on ether either. I am attaching a video of the injectors at start up. I am thinking my first step is to take out the two injectors in this video and inspect and replace o-rings. The truck has 118,000 ROUGH miles on it.

 

Maybe a week since service. Not long. Everything Fuel Wise (pumps, sensors, and check valves even line to pump) was changed last year.

 

Just looking at the oil that seems to run out from the base of the injector. It will sometimes have a burp when running flat out. If you come to a stop it shuts off. Sometimes it will start back. Sometimes it will not. It was towed in Thursday because it would not start back. It sat in the shop Friday and I took the valve cover off and filmed this video. It of course cranked. The only codes in system of Injection Pressure and low cranking fuel pressure. The fuel pressure never changes whether it cranks or not. So that is constant.

 

Was so busy today I did not get a chance to pull all of the injectors out. I did get the hard ones first though. The pictures below show #3 injector (with old o-rings) and #6 injector (with new o-rings). #3 top o-ring and the backup ring both show slight damage. Will let you know how it goes after I complete them all and fire up. You can also see how much further the o-ring sticks out compared to the old injectors.5

 

OK ended up putting another HEUI pump on it. After several runs it came in and the actual and desired injection pressure was not meeting at all. Before this I would hook up computer and never could get anything injection pressure wise other than occasional low at start up. The pump that was on the truck was only 8 months old and has about 6k miles on it. Hard miles though. Will let everyone know how it goes.