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New to posting on the forum, but have been using it as a resource for a while. Thanks for having me. Have a couple questions about a fuel pump on an ISX12

Had a fuel pump go out on ISX12 a few weeks ago. Had it towed to my shop and called mobile maintenance out from dealership to assist in diagnosing issue. Mechanic pulled the head off the fuel pump and found the ceramic plungers stuck in the head. After having a heck of a time finding parts for the ISX12 fuel pump, found the repair parts for this head. The new kit came with steel plungers. Replaced plungers and tappets. Reinstalled and truck fired right up. We ran it around the shop a couple of days, had to do exhaust manifold and get the concrete jack hammered out that setup when it shut down. Go to put it back in service, load the truck and it made it 5 miles down the road and bam, engine shut down. Had truck towed back to dealership, they pulled the head off the fuel pump and the new plungers were stuck in head. They recommended changing out the whole fuel pump so had them do it. Truck has been running fine ever since. My questions are, first has what would cause the plunger to stick in the head and secondly, what kind of labor time should I expect on changing out a complete fuel pump?

Thanks

Not sure but when I do mine I just change the whole pump because I usually see wear in the barrels of the pump that I don’t like so I just change the whole thing.

By whole thing, are you referring to whole pump or head? If you mean head, Cummins doesn't have a head for the pump that came on this truck.

(10-07-2020 )RMKC MIKE Wrote: [ -> ]By whole thing, are you referring to whole pump or head? If you mean head, Cummins doesn't have a head for the pump that came on this truck.

I know nothing about the X12, but if like the CM-2250, cummins updated the pump from I believe three cylinders to two, or vice versa. Odds are, you need an entire new pump. I would register the motor on quickserve, you will need your engine serial number (EIN), register it and see what Cummins says in the manual and parts section, you will see everything the dealer sees. https://quickserve.cummins.com/info/index.html

That seems to be my issue is that it's an ISX12. I'm registered on quickserve already, but thanks for the advice. Luckily I have a friend at Cummins that helped us even find the parts for the fuel pump that is on that ISX12, nothing showed up on the actual parts section. What kind of time does it normally take to do a whole fuel pump swap?

Looks similar to the X15 pump, so what, 4 hours?