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Oil pump housing failure, probable rebuild...

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On my way to elk camp I developed a whine from the engine. I presumed it was the vacuum pump failing and removed the belt to install my non-vacuum pump belt. While the belt was off I started the motor to verify the noise was belt driven, it wasn't, pointing to a gear noise. Due to my remote location I drove the truck 15 miles to camp, 45 miles closer than town. I shut the truck down and waited. Two days later I started the truck and the noise was present instantly and got much louder when the oil pressure came up, I have a real gauge. This further led me, and my mechanic, the believe it was the gear train. We decided I should have it towed, and my insurance covered the tow (what a PITA) 255 miles to the shop. The truck got delivered yesterday and the mechanic got the timing cover off today, and it's amazing I made it to camp. The oil pump housing broke right where the idler gear is. The broken housing caused the gear to contact the housing and allowed the gear to run crooked and damage the crank gear. Somehow the cam gear also has a broken tooth, probably from a piece of the broken housing contacting the gears. The oil filter was full of metal, some of which was copper colored. The magnet in the pan had some metal on it, but not overly fuzzy. The big questions are how much metal got thru the filer? I run a 15um filter vs the OEM 40um filter. How much contaminated oil splashed up on the crank and cylinders while I was driving after the failure? I probably put about 45-60 minutes of run time on it from when I heard the noise. Before hearing the noise I was doing 30-50 on a dirt road with mud tires, the noise could have been masked for several miles. What else is damaged that we cannot see?The engine is coming out this week.. time will tell how far we tear it down. But probably all the way if it's out. I will be rebuilding it with QSB early CR pistons and nozzles. I have 93k miles and 2800 hours on the motor, surely no where near soon enough for this kind of failure. I bought a Cummins because they don't this!!Have any of you seen this before? My mechanic hasn't. Sorry, no photos yet. I wasn't thinking about that when I got to the shop. On a positive note I had a great week with my dad and brother, and filled my elk and deer tags.

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I have only seen one oil pressure/pump problem and that was a delayed pressure build up that took about 15 seconds to build pressure then it would be completely fine. I havn't even heard of any oil pressure problems.

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Sooo are you still under warranty?As well, atleast someone has killed something this year! I've had zero luck getting anything... Freezer is looking a little barren...

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That sucks.................too bad I can't see the carnage in person to do some failure analysis. I can say one thing from having been through several cummins technical classes over the years is that by running a smaller UM oil filter, cummins would point to that as a partial cause to the failure right off the bat. Filtering the fuel cleaner is ok but when you mess with running different full flow oil filters Cummins takes issue with that in a strong way.

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Surprisingly the pump still worked. As far as micron ratings of the filters Cummins offers 2 different filters, and Mopar a 3rd with many others on the approved list. Micron rating is not the most important thing, it's flow rating. The filter I use has better flow properties than OEM. To say a failure of any kind, let alone this, is based on cleaner oil is ignorant any way you look at it. Lack if flow means heat, and heat leaves marks and there are none. Not to mention that the oil pump is lubed by pre filtered flow, so even it the filter limited flow the pump lubrication would not be effected. The the biggest issue I have seen Cummins dislike about several filters is ones like Fram that come apart and clog piston cooling nozzles.

post-10129-138698210138_thumb.jpg

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Any idea if'n it's related to the internal engine mods you've done???? Turbo, cam etc.??

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Just passing on the info I get from the horses mouth in this case cummins, it's not my opinion. I won't get into a filter spec debate here.By looking at the housing it is a secondary failure for the housing to break clean like that, which looks to be a quick fracture from what I can see in the pics. Something mechanically had to break first. what do the teeth on the gear look like?After rereading the original post you stated a cam gear tooth was broke off, I would lean towards that being the initial failure, but not being able to inspect all the parts closely can't know for sure.

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Nothing I have done to the motor has been near the pump, nor would it have an effect. The missing tooth on the cam gear is odd, but right now we are thinking its a result of damage to the crank gear thou still unknown.Aside from some marks on the side of the idler gear where it was contacting the housing the gears look fine. There is no indication that anything went thru the gears to cause the breakage. I think anything that would have gone thru the gears to break the housing would have dislodged the idler gear, but it didn't. Hopefully more will be known by the end of the week.

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Gear failures can be tricky for sure. My vote goes to the cam gear tooth failing, dropping and catching the idler gear just right and breaking the housing depending on how it hit it could have broke and still not showed any damage to any other teeth. The crank gear damage sounds like a "Result" of the "secondary damage" the pump hsg caused by the "root cause" the cam gear tooth.This is just my unexperienced opinion though. :2cents::whistle:

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Ouch! This is going to hurt real bad.Makes a grown man cry.Good luck on your repairs and what ever else you decide.

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Gear failures can be tricky for sure. My vote goes to the cam gear tooth failing, dropping and catching the idler gear just right and breaking the housing depending on how it hit it could have broke and still not showed any damage to any other teeth. The crank gear damage sounds like a "Result" of the "secondary damage" the pump hsg caused by the "root cause" the cam gear tooth. This is just my unexperienced opinion though. :2cents::whistle:

It's certainly possible, hopefully we find a smoking gun. The direction of rotation could cause it, but I still think it would have dislodged or done more damage to the gear. If that is what happened, what caused the cam gear to break?

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It's certainly possible, hopefully we find a smoking gun. The direction of rotation could cause it, but I still think it would have dislodged or done more damage to the gear. If that is what happened, what caused the cam gear to break?

If you can get me some very clear detailed pics of the broken gear tooth with pics of the broken casting area of both the tooth and the gear most importantly, Hopefully I can see if it was a casting defect or a break caused by some other reason.

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I plan to get some better pics when it's apart. To me the tooth does not look like a casting failure, it's chipped about 2/3 off width wise and about 7/8 of the top edge of the tooth is missing. To me that is a break from something else, looked like the R&P I had a R&P bolt go thru 10 years ago on a Toyota.

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I have my failure analysis bible laying right next to me at work and will take it home this weekend if you do get pics by then.I attended a week long Catapillar failure analysis class in january and we spent most of the time learning metalurgy and how to analyze this exact type of failure.

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Given the geometry of the gears & pump, is there any chance that what caused the broken tooth caused the housing failure? Meaning, that potentially something lodged in the gear, breaking the tooth and the housing?

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Ouch... That going to hurt more than the turbo I fed a hose clamp. Ekkk... I kind of wonder about the cam gear since its not stock and maybe there was a minor defect in the gear. Since between bill and yourself you got more information to nail down this issue.

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Well there went my though. Man I got to admit that sucks to have something a small as a gear tooth wipe out the oil pump and possibly the rest of the engine. So did you get to open up the engine and verify the internal stuff like bearings?

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The cam gear is stock, just the cam isn't.

Knowing this is what makes me think it was the cause, something could have happened while doing the gear swap from one cam to the other, I have seen several engines over the years that had massive damage from cam gear failures and a couple were after a cam or gear swap.

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The motor isn't out and apart yet, time will tell but it seem to have had a lot of metal go thru it. I really feel that if there is any wear it needs to be fully torn down and tanked, then put back together. There is 40K miles on the cam, and over 1800 hours. While anything is possible the shape the gear was in doesn't indicate a break from anything off the motor. It looks like something went between it and the crank gear, and the brunt was taken by the cam gear.Really wanting to see all the parts when its out.

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I really feel that if there is any wear it needs to be fully torn down and tanked, then put back together.

I myself would do the same thing, total tear down

There is 40K miles on the cam, and over 1800 hours. While anything is possible the shape the gear was in doesn't indicate a break from anything off the motor. It looks like something went between it and the crank gear, and the brunt was taken by the cam gear.

This is a possibility as well, shock loads are a common cause of gear failures, but I need to see what the broken part of the cast looks like to determine what kind of break it was.

Really wanting to see all the parts when its out.

Make sure to keep all the pieces including those that may be found in the oil pan and inspect things very closely as you disassemble, don't do like some and rip and tear as fast as they can until they have a pile of parts and then sift through them after the fact.

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