Cummins N14 oil pump damage

[OVERKILL]

Slammds15 asked me to snap some pics of this:

Details:

-2000 International straight frame boom truck
-Cummins N14 Select Plus
-372,562Km
-12,440.6hrs
-Quaker State 15w40
-15,000Km OCI's
-Fleetguard filters

 

[onion]

The gears commonly flake on N14 oil pumps. Can't say why- Kestas would be better qualified to venture a guess on that. But I can say that I've seen it plenty of times. Same goes for the N14's direct ancestor, the 855.

I can't see that regulator valve well enough to comment on it directly. But if that wear patch is just shiny, but not scored or indented, then I'd reinstall the valve and forget about it. Maybe shine it up with some scotchbrite first.

Here's a quick tip on those oil pump setups that you maybe aware of, but lots of people aren't. There's a square seal ring inside the cast aluminum piece that slides over the oil pickup tube going to the oil pan. It's a good idea to replace that square ring along with the o-ring and gasket, as they tend to start sucking air when they get old and rotten... causing low oil pressure and pump damage.

 

[OVERKILL]

The regulator was scored. The entire pump assembly was replaced.

 

[onion]

Yes, the gears alone would warrant pump replacement.

 

[OVERKILL]

Yes, they were heavily pitted.

 

[rshunter]

Nice. I've only run a couple of Cummins over the years, without a major problem to speak of. I always seemed to err toward CATs, though. I quite like the Volvos I've got now, as they haven't skipped a beat. Have you guys seen much of this in such a low mileage truck? Did the unit have unusually high hours on the engine due to PTO use?

BTW, I noticed how you strategically got that Timmy's cup into both pictures there, Canuck. God I hate the "Americanization" of the TH product down here in the States. It just doesn't live up to my memories, but then I suppose little does...

 

[OVERKILL]

Hours are in the original post: 12,440.6.

I'm not Jon, so I can't speak as to the frequency at which he sees this stuff, I'm sure he'll chime in shortly.

Yes, that's my XL 1-cream there you spy

 

[rshunter]

Originally Posted By: OVERK1LL
Hours are in the original post: 12,440.6.

I'm not Jon, so I can't speak as to the frequency at which he sees this stuff, I'm sure he'll chime in shortly.

Yes, that's my XL 1-cream there you spy

Can you tell I'm in the over-the-road business? I saw the mileage and completely missed the hours...

Yeah, I'm one of those people that can take a glance, at a picture or a view, and instantly spot things. I'm always saying things like, "Hey! Take a look at (insert anything here)!". To which everyone responds, "Where the heck do you see that?". Followed by my predictable, "IT'S RIGHT THERE!!! HOW CAN YOU NOT SEE IT? IT'S RIGHT THERE!!!".

But hey, you know what they say about Canadians, right? "A Canadian and his Tim Horton's cup is rarely parted..." I should talk, though. I've still got two very, very old Tim Horton's mugs. Yellow plastic jobs from the '70s, with their little mascot on 'em. Yeah, real old school...

 

[slammds15]

I haven't seen this failure that often. I'm not well versed in this engine. My specialty is the ISX and ISM. The truck came in for low oil pressure, it had logged many OP DTC'S. After verifying electrical sensor operation I checked the OP regulator and found it to be heavily scored. Rather than replace it I decided to check on oil pump health and discovered what you see.

Originally with the engine oil at 200F there was 8-9 PSI OP. After the new pump there is 12-15 PSI at 200F. Cummins states that 10 PSI is the minimum required but the engine is still on the border line. I'm currently awaiting authorization to further diagnose. I'm suspecting a possible worn ACC drive bushing or worn crank/cam/rod bearings. Usually if the bushing is worn severely the ACC drive pulley has some sort of the leak, there isn't one. The engine has no abnormal audible noises. any one with previous experience please feel free to chime in.

 

[slammds15]

There is new engine in the engine as well. XD3 15w40, there was only approximately 4000k on the old oil.

 

[onion]

I worked at a Cummins dealer for several years in the mid/late 90's, left in 2000. The ISX had just come out, so I've barely touched one- same goes for the ISM. But I've had more N14's, M11's, L10's, B's and C's apart than I could possibly recall. I agree about the N14's accessory drive- if there's a problem, then the seal will usually be leaking... often a spun bushing due to some gorilla tightening the fan belts.

Those N14's never had much oil pressure even when new. I think your oil pump and regulator will likely bring it back up to acceptable levels, but it might not be a bad idea to check a few bearings.

 

[slammds15]

I just find it odd that the oil pressure is so low. This company is top notch for maintenance. Every 15,000km the oil is changed and every week to two weeks the trucks are greased. They run fleet guard filters and Quaker HDX 15w40 bulk oil. I see no reason for failure... I've been wrong before though.

Lowest spec is 10psi and this engine is just floating above it.

 

[Doug Hillary]

Hi,
slammds15 - Like "onion" indicated, it is interesting to trace Cummins back a few years, now, the 903 and 903T (or the 555!)

The 855-N14 families had a good reputation here (well Big Cams at least) save for plastic non secured water pump impellors and etc. We called them the "Xmas" engines - my Clients always pulled them in during the Xmas holiday period and rolled the bearings etc. Some in-frame rebuilds were needed then too. The bearing roll was usually required because of falling OP! I'm not sure if it was always restored though