Engine/Transmission (1994 - 1998) Necessary to run oil filter bypass valve??

[JGheen]

Ok, I have had an issue with my oil filter leaking upon start-up everytime recently and it still does it but this time it completely blew the oil seal out and made a HUGE mess. This has not been caused by double stacking the filter seals and I have never done that.

Anyway, I believe my issue was a possible sticking oil filter bypass valve and I want to know if I can run the engine without one. This truck is no longer a daily driver, strickly sled puller and will probably never see the street again. Will running no filter bypass valve affect oil pressure at all? I removed the oil cooler/filter housing to inspect everything and the bypass valve seemed to be operating properly but I took it out anyway. Apparently my oil pressure regulator and spring are working cuz they are not sticking, takes a good press of the finger to press the regulator but it works.

I change my oil and filter very fequently now that it is a sled puller and I highly doubt not running the bypass valve should hurt anything but I wanted to check with my fellow diesel heads first.

Thanks for the advice guys, hopefully I found the culprit of this ongoing problem I have been having.



Joe

 

[JFaughn]

I've never been a fan of eliminating parts that are like fuses [ there may be exceptions , not this one ] you know how much time & money you put in , its not worth saving a few bucks .

 

[DavidC]

A bypass valve is designed to open when pressure becomes excessive and needs somewhere to go. Running with out one will result in poor oil pressure and low oil circulation and may cause engine failure. Blocking this device will cause havoc such as filter explosions and other problems. Moral of story: Fix it.



Dave

 

[Vaughn MacKenzie]

Yes if you remove the valve it will pretty much reduce your oil pressure to nothing. It plays a major part in determining your oil pressure. I'd get it fixed asap 'cause you could damage your oil pump, let alone causing bearing damage.

 

[JGheen]

Well, I guess I will have to wait until Monday to get one sent down from Cummins West as there are no Cummins parts dealers down here in northern LA for miles aside from the stealership and of course they don't have one in stock.

Has anyone had anything like this happen before and it be caused by the oil filter bypass valve sticking? I can't say for sure that it was sticking cuz when I removed the oil filter housing/cooler from the engine, it seemed to press in and spring back just fine with a small screwdriver. Maybe I dislodged it when I did that and I also removed the valve for further inspection and it was slightly damaged being removed.

Could there be another oil passage somewhere being blocked to where it would cause a filter seal failure and not be caused by a faulty bypass valve? I just want to make sure I have checked all the other potential problem causers before i go putting this back together and it happen again after a new bypass valve.



Thanks again, Joe

 

[JGheen]

Just another quick thought, could my HG oil passages have been hurt at all by this filter explosion? I mean, if the pressure at the filter was high enough to blow that seal out, should I be worried about the HG at all?

Also, Vaughn spoke of damaging the oil pump but i assume that would be due to the lower oil pressure that would have been caused by not running the bypass valve, correct?



Thanks again and again, Joe

 

[DavidC]

Either the bypass is not opening at the correct pressure or maybe a blockage in the bypass return passages not allowing the pressure to return to the sump or a blockage leading to the bypass valve and the bypass not seeing the over pressure. I have had experiences with a bypass stuck partially open (a wire wheel strand stuck in the valve not allowing it to close) on another vehicle but NOT a Cummins. Did you notice what the oil pressure was when this happened?. The pump will not have any problems with free flowing oil as long as it is immersed in oil but if it is run under high pressure it and the associated pump drive system could be destroyed.



Dave

 

[HEMI®Dart]

First I've ever heard of the problem. Somethings gotta be wrong w/ the bypass valve. I'd Replace the cooler.

 

[JFaughn]

I would have to look at an exploded view again , but there can be as many as 3 , oil filter , the OF adapter , then in oil pump .
The OF seal is like a fuse , should be a lot easier to blow than HG .
Doing a pressure test all along the oil train to find blockage , need an oil path diagram ?

 

[JGheen]

need an oil path diagram ?

Yeah, I have one but it is not very descriptive as I thought it would be. My small operation and maintenance manual illustrates the oil going from the sump to the pump, to the oil pressure regulator valve, through the cooler, then the bypass valve, then the filter and out to the bearings and valve train from there. Kind of weird how it goes through all those other places before the oil actually hits the filter.

Just wondering if there could be another place in the oil passages that could be plugged somehow since the oil blew out of the filter where it goes into the filter. So that would tell me there could be something blocking it downstream on the clean side of the filter toward the bearing/valve train passages since the oil apparently could not pass through the filter causing the seal to blow. I highly doubt a brand new Fleetguard Microglass filter could have suddenly clogged on top of a possible faulty bypass valve causing this blow-out.

Just gonna go ahead and order parts tomorrow and hope for the best. Going to price out a new filter housing as well as crack check the old one at work tomorrow.

Man this is going to suck if I get it all back together and the filter still leaks or blows out again along with a pull coming up on Sunday. :{ Hopefully it was the bypass valve, which I am still confused on how that could have actually caused this filter failure since the filter was brand new.



Joe

 

[JGheen]

Well, I can't figure this out for the life of me. :{



Got it all back together and the filter still leaks but I was able to let it warm up fully to operating temp, letting the oil pressure come down and the oil thin out and the filter seal held during free revs to 2K-25K RPM but the filter still leaks upon cranking and then as soon as the engine fires and runs the leak stops.

Replaced the oil filter bypass, regulator spring and piston. New filter housing gasket and cooler gasket and also a brand new oil cooler. The engine is not knocking and runs great, doesn't seem to be starving for oil anywhere, it has oil pressure, according to the dash gauge, which is in fact a very new sensor as I replaced the sensor when I did the headgasket about a year and a half ago. It is not overheating and there is no metal coming out of the oil nor in any of the old oil filters that leaked as well. The blow-by vapor level seems to be slightly up(could be a figment of my imagination with all the frustration) and I double checked all the vacuum points, no leaks there.

Anyone else's advice or thoughts on this is greatly appreciated, but in the meantime, I am going to my next sled pull and hoping for the best. Just gonna let it warm-up real good before any higher than idle RPMs and see how it goes... ...



Thanks, Joe