Warning: Prefilling An Oil Filter Can Be Dangerous To Your Engine

[rjones]

My 3 diesels I had I never ever prefilled no problems what so ever all oil analysis came back fine no turbo issues etc..... I really dont think its necessary.....

 

[Teich]

Interesting to fill or not! I don't fill use 0/40 syn. oil seems to work out ok. Changed an awful lot of oil ( 40 years wrenching) we never prefillled it takes time. last place i worked govt agency, highway maintance equipment, the operators changed the oil (this was good!) they never filled never lost an engine due to that. Had a L10 in grader went 26000hrs. never filled all sorts of Cummims, DDA's and all the others never an issue. Picked a lot of 'foil' put of top of engines especially the 671's. I don't thik a "dry" start is a problem with our engines, compare them to a N14 they have much longer route from oil pump to bearing than a 5. 9. done from, or, at idle shouldn't be a problem. The Dodge uses 0/40 year round! Laurie

 

[Gonzo 1066]

I have been a diesel engine mechanic for most of my adult life. I have changed oil on engines hundreds of times without filling the filters. Many diesel engines use inverted filters so it is impossible to pre fill... ... ... ... ... . So let me get this straight. We want to be extra good to our mighty Cummins. So we pre fill the oil filter and STRAIN THAT OIL WITH A PAINT FILTER::???????????? This has to be the stupidist thing you could possibly do to a $15,000 engine. DONT FILL THE FILTER!!!! this is a prelude to disaster. .



If you are ever witness to the new engine start up on ANY assembly line the oil filters are NOT pre filled. Do you think Cummins, Cat, John Deere, Detroit do not know how to start new engines?? Ah yes the new owner of a pickup truck MUST know best. .

 

[Gonzo 1066]

Good advice, but I'm still prefilling... That's a whole quart of oil that has to fill that filter before the turbo gets fresh oil. Im not sure the turbo will have a sufficent enough oil film

on the bearings to protect it til the fresh reaches them.

DO yourself a huge favor, remove the air intake from your turbo. . Have someone start your engine for you and see if the turbo actually turns at all till you open the throttle a bit. . If it does turn just a bit there is MORE than enough oil to protect it. How is it possible that class 8 truck engines will turn more than 750,000 miles on the original turbo? and never have the filters prefilled?? Being a diesel tractor puller, where the turbo is on top of the engine I have watched this MANY times. The other interesting test is to remove the turbo oil feed and crank the engine, the oil appears very quickly and there is LOTS of it. .

 

[brods]

I have been a diesel engine mechanic for most of my adult life. I have changed oil on engines hundreds of times without filling the filters. Many diesel engines use inverted filters so it is impossible to pre fill... ... ... ... ... . So let me get this straight. We want to be extra good to our mighty Cummins. So we pre fill the oil filter and STRAIN THAT OIL WITH A PAINT FILTER::???????????? This has to be the stupidist thing you could possibly do to a $15,000 engine. DONT FILL THE FILTER!!!! this is a prelude to disaster. .



If you are ever witness to the new engine start up on ANY assembly line the oil filters are NOT pre filled. Do you think Cummins, Cat, John Deere, Detroit do not know how to start new engines?? Ah yes the new owner of a pickup truck MUST know best. .

You obviously did not read the thread. It is Dodge AND Cummins that are recommending prefilling the oil filter. Everyone saying not to prefill, like yourself, are the ones claiming to know more than the manufacturers!

 

[Yo Hoot]

I just wish they would stop using those foil seals. My thumb hurts after poking them out. I don't pre-fill my filter.

BTW here is the page from the manual... use Ctrl + on your keyboard to zoom... . Ctrl - to unzoom.

 

[NIsaacs]

The control + to zoom is awesome, thanks, I can use it to type while I post... I prefill... .



Nick

 

[Gonzo 1066]

You obviously did not read the thread. It is Dodge AND Cummins that are recommending prefilling the oil filter. Everyone saying not to prefill, like yourself, are the ones claiming to know more than the manufacturers!

AND the manufacturer will WILL deny warrenty if there is a forign object in one of the piston cooling jets. .

 

[AH64ID]

This last time I changed the oil (filter empty) I unplugged the 3 injector harness plugs and spun the starter for about 10 seconds on 30 seconds off, 10 seconds on. I then plugged the harness back in and started it up (after clearing the codes) and I had oil pressure before the gauge came to life, this is MUCH faster than any start, any time of year.

The oil pump moves so much oil that as long as you add warm oil to the block (garage temp for most of us) your filter will instantly be full. Ever read the threads where peoples filters are 1/2 full when they remove them to change the oil? That's half a filter needing oil nearly every start and that does no damage, the additional 1-2 seconds every now and then isn't going to hurt. Like I have previously said, oil psi comes up faster changing the oil with an empty filter on a 45° day, than it does on a 0° day with a filter full from the previous run.

 

[Yo Hoot]

Listen up,



Oil does not exit bearing surfaces and all other critical lube areas in the time it takes to change your oil and filter. In addition, you could probably run your engine with no oil for a lot longer than you would think before damage occurs... that would be idle only. That is because there is residual oil on everything and there is still oils moving around in the galleys.



I never even blink an eye starting my truck up on a non pre-filled filter. Matter of fact most recommend taking the rpms up to get the pressure going sooner rather than later... especially when starting a fresh motor.



For those who have lubiphobia, you can buy a preluber that gets pressurized during run time. When you turn the key on, a solenoid opens and releases the pressure before you crank it.

 

[Teich]

Changed alot of oil in Cummins engines NHC 220's 250's 335's N14's never filled the filter never had one problem, hard to fill a filter when it mounts on it's side is (horizontle). They all ran no noise rattles etc. Laurie

 

[Moe]

I always prefill, unless the filter isnt upright. I also have a Detroit Diesel in my motorhome with over 600,000 miles and have never had a problem like some describe. Common sense dictates that you would always remove the seal completely before pouring in. Just my thoughts, Moe

 

[brods]

This thread brings the awesome!



So to all those so strongly against prefilling, please explain why CUMMINS recommends prefilling the oil filter if it is so risky. Is there no benefit what so ever? Are we to believe that the manufacturer of the engine with all their technical knowledge and real world experience on millions of engines somehow got this so very wrong??



Bottom line is do whatever makes you comfortable. If prefilling worries you, then simply don’t do it. For myself, until someone presents solid evidence which clearly shows Cummins is wrong, I will continue to follow their recommendation to prefill the oil filter. YMMV

 

[NIsaacs]

Changed alot of oil in Cummins engines NHC 220's 250's 335's N14's never filled the filter never had one problem, hard to fill a filter when it mounts on it's side is (horizontle). They all ran no noise rattles etc. Laurie

I hated those PITA horizontal, even the later vertical canister type cartridge filters! So much better when the spin-on was introduced. I never cared much for the huge nasty 'ole Lubrifiner bypass filters either.



Nick

 

[Yo Hoot]

This thread brings the awesome!



So to all those so strongly against prefilling, please explain why CUMMINS recommends prefilling the oil filter if it is so risky. Is there no benefit what so ever? Are we to believe that the manufacturer of the engine with all their technical knowledge and real world experience on millions of engines somehow got this so very wrong??



Bottom line is do whatever makes you comfortable. If prefilling worries you, then simply don’t do it. For myself, until someone presents solid evidence which clearly shows Cummins is wrong, I will continue to follow their recommendation to prefill the oil filter. YMMV

I don't think anybody said Cummins is wrong. They are just pointing out that if you get any foreign matter in there, it's after the filter element and will go directly into the engine.



Same problem with prefilling fuel filters which is even more critical. I never prefill fuel filters either.

 

[mwilson]

I hated those PITA horizontal, even the later vertical canister type cartridge filters! So much better when the spin-on was introduced. I never cared much for the huge nasty 'ole Lubrifiner bypass filters either.



Nick

Those were a complete PITA to change. First tractor I drove was a White 9000 with an NH-250 that had the horizontal oil filter. That filter was in there so tight that White made a semi-circle in the lower frame rail flange so you could flip the canister upright and get it down out of there.

Then you had to run it back up through the rail with the new filter element in it, lay it down and try to get it tight against the filter head without pinching the o-ring. A three handed job... ..... and let me tell you it got dirt in it, could not be helped.



Mike.

 

[brods]

I don't think anybody said Cummins is wrong. They are just pointing out that if you get any foreign matter in there, it's after the filter element and will go directly into the engine.



Same problem with prefilling fuel filters which is even more critical. I never prefill fuel filters either.

No, no one has yet come right out and claimed Cummins is wrong, but some are telling others to ignore Cummins recommendations and not to prefill. Not sure how that logic works. If prefilling is not wrong and Cummins recommends it, then it should be done, yes? So telling people not to do it has to mean Cummins must be wrong, but you say that is not true. . …. So confusing, lol.



A fuel filter is much different for several reasons. And there is no need to prefill since the lift pump can and should be used to prime the filter prior to starting the truck.



If you look at some of the ISB oil change recommendations in other applications (like welders, pumps, etc) prior to starting the engine Cummins recommends to crank it without fuel until the oil pressure comes up. Since it is not really practical for the average pickup owner to disable the fuel supply and crank the engine without starting it, I wonder if that is one of the reasons why they recommend prefilling for our trucks.



I did contact Cummins about it and posted their response earlier in this thread. Unfortunately they did not explain why they still recommend the practice though they do warn to be careful of the foil.

What strikes me as odd is it appears nobody can list all the reasons why Cummins recommends prefilling, and without knowing why something is recommended how can one make an informed decision not do it, let alone encourage others not to do it?

 

[Yo Hoot]

I think they recommend against prefilling only because there is less chance of accidentally getting dirt in there. And probably based on lots and lots of members with hundreds of thousands of miles without prefilling... well you get the picture.



I say whatever floats your boat just be extra careful if you prefill.

 

[NIsaacs]

Same problem with prefilling fuel filters which is even more critical. I never prefill fuel filters either.

This makes sense on the electric lift pump trucks, but not on the manual pump trucks. You will be manually hand pumping the lever till the cows come home. Also on the Cummins engines with the PT fuel pump systems, if you didn't pre-fill, that sucker ain't gonna start. There wasn't any provisions to manually bleed them, other then running the starter.



With the large 4" fuel tank fill opening, just stick your hand and filter down in the tank and fill it, then smell diesel for the rest of the day



Nick

 

[Bill Stockard]

With the large 4" fuel tank fill opening, just stick your hand and filter down in the tank and fill it, then smell diesel for the rest of the day



Nick

... and you just pre-filled your fuel filter with unfiltered fuel! It probably didn't matter with the old PT systems. :-laf You could prefill the filter with hydraulic oil and it would still start and run.



Have you ever prefilled the fuel filter with B-12 Chemtool and watched the results?



Bill