Aluminum in LPOP regulator?

DamageINC · February 25, 2011

Ok, here's a fun one. One of those "the customers story doesn't add up with what I found" ones, hehehe.

Our shop owner is friends with another shop owner who does lots of heavy duty diesel work, but usually ships his 6.0 stuff to us because I work here and have lots of dealer experience with them.

Soooo, basically he drops a truck off, 06 model F-250 6.0, tells me that he put a HPOP in it for low cranking ICP and that it ran fine for a few hours and then shut off on it's own. Cranking ICP went to 0psi, totally dead. He replaced the IPR and ICP sensor and still had 0psi cranking, so he towed it to our shop.

I get in, verify no ICP cranking. Also notice that the oil pressure gauge on the dash will not move. I go and take out the oil filter - the thing is BONE DRY. Has never seen a drop of oil. This filter was installed AFTER the vehicle died out and wouldn't start, apparently. But he told me that he has no clue how old the filter is.

Regardless, the drainback valve isn't stuck open, and if I manually depress the standpipe and crank it, the filter housing still won't get any oil. So I decide to yank the regulator.

It didn't seem seized at all, but there was a decent sized chunk of aluminum (maybe half the size of a valve core) resting on top of the regulator piston.

So, off comes the LPOP. Small, VERY shallow scoring marks on the LPOP cover plate, including a tiny little gouge about the size of a grain of sand. But no real obvious marks or indentations on the Gerotor assembly itself, or in the timing cover where the LPOP atually sits.

NOW, it turns out that the vehicle was also in for an oil leak on top of the engine, which was determined to be coming from the oil filter housing, I guess one of the mechanics at the other shop had the oil/fuel filter housing off of the oil cooler assembly and replaced the gasket there.

SOOOOOO, my questions - what could the other shop have messed up while servicing the oil filter housing (which explains the new filter) that would prevent the oil filter housing from getting any oil flow? AND, where else could the aluminum on the LPOP regulator have come from if there are no signs of real damage to the timing cover? I can't imagine that the oil cooler itself is coming apart and leaving bits of aluminum in the oil.. I thought maybe one of the fuel injectors could have broken apart, but again, this looks like it was a piece of cast aluminum.

I'm debating whether to yank the timing cover completely off or take apart the oil cooler, but I'm not sure I'd know if I'd recognize a problem there even if it was staring me in the face. The coffee table book gave a decent rundown on the oil flow through the oil cooler/filter housing, but it doesn't make sense to me why the filter housing won't fill up still. I need to be edjumikated!

lmorris · February 25, 2011

To my knowledge there is nothing in the oil filter housing/base to stop oil flow to the filter. Taking apart the oil cooler won't help you either.

Typically any debris in the LPOP comes from the top oring on an injector, a lifter roller needle or the fitting on the HPOP.

If the LPOP doesn't look to bad, try to clean and re-install the regulator and see what happens.

If you still have no oil to the filter you may need to tear this down and find out where the debris came from. You may want to check all the rockers while cranking, lifter failures causing low oil pressure are not uncommon.

Bruce Amacker · February 25, 2011

The chunk could also be an unrelated piece of casting flash leftover from engine production.

We (a cust of mine) just went through this a few weeks ago without much learned or the real issue solved. You should probably read this post- it will sound familiar.

http://www.forddoctorsdts.com/forums/ubbthreads.php?ubb=showflat&Number=35854#Post35854

I can't think of what the previous tech could have done during the leak fix to stop oil from reaching the top of the engine. If I were in your shoes, I'd replace the LPOP, check the regulator and reinstall it, and advise the cust where you are. Let him call the shots to keep you out of the hot seat, but chances are good it will be fine with a new LPOP.

Lay the gears on a table and check the distance between the tips of the teeth, IIRC it's supposed to be .005" or so. Commonly I measure bad ones at .012-.015".

Keep us informed.

Good Luck!

Posted Image

Good Luck!

DamageINC · February 26, 2011

Well, I got around to screwing with this thing some more today, went ahead and peeled the HPOP cover off and sure enough, there was a mark on the rear cover from a little make-out session with the old STC fitting. I can only assume that it was part of the fitting that I found in the regulator Posted Image

As for the timing cover, I pulled that off and gave the regulator bore a good thorough inspection. Although I couldn't see anything wrong, sliding the old regulator piston in & out, it would noticeably bind up pretty heavily every now and then unless it was DEAD straight. I have no clue why there was no pressure when I removed it originally, maybe it was just one of those "bad timing" things, but I'm pretty sure that the regulator was stuck cock-eyed in the bore and just dumping the oil right back into the pan. We have a new Timing cover/LPOP on the way for tomorrow morning, and hopefully this thing will be running by noon.

I'll keep you cats posted with the results, thanks so far for the input though - this place has been a lifesaver Posted Image

Mikill · February 26, 2011

Kind of a crazy question but is there oil in this engine? I have seen a tech chase his tail for a few hours trying to figure out a no oil pressure concern and didn't even think to check the oil level.

GregH · February 26, 2011

Second on check the oil level. If it is ok, it might be a good idea to drain what is there and check the magnet, maybe even pull the pan and look at the screen..