Oil & Fuel Chnage oil, leave filter unchanged

[jwnge]

My old Daddy use ta say, " changing the oil and not changing the filter is like washing your feet and putting the dirty socks back on." I always change the filter when changing the oil.

 

[sandman2234]

I think if I were going to half way do it, I would probably replace the filter and leave the oil alone, but I don't think I would do it that way either, so it is a mute point.
Change both...
David from jax

 

[Soundguy]

I've done that sometimes on a first oil change on a new-to-me tractor.. that is.. change oil, then change the filter after a few days of running.. then cut it open and see what came out of the engine... as a way to see if the prev owner let it get real cruddy.. or just semi-cruddy.. then slap a new filter on and go, as long as the new oil still looke dok, and not too much stuff came out of the engine.

On my jd-B.. so much junk came out of the engine i had to do 3 oil changes and 2 filters on it the first week i owned it..

Soundguy

Soundguy

 

[TrippleT]

While oil may not wear out, it becomes contaminated, oxidized, etc. And because of this, the filter should be changed at the same time as the oil is changed. What role does the filter play? It is to filter the contaminates out of the oil. Particles of metals and other things that get into used oil. Hypothetically, if a filter becomes plugged with these contaminates what happens? The bypass opens and you have no filtration at all. Change both at the same time for long engine life. Changing at what, was it 12 hours, seems exterme to me unless he is operating, in some unimaginable to me, extreme condition.

 

[Doc_Bob]

On my jd-B.. so much junk came out of the engine i had to do 3 oil changes and 2 filters on it the first week i owned it..

Soundguy

Before you cut open the filter, did the oil give you any hint that it was dirty? or did you have to cut open the filter to really know?
Bob

 

[john_bud]

First off I would like to say that filters do just that -- filter out stuff --. They do it by having wee little holes, pores, or spaces in the filter media that allows the fluid to pass but not the solids. Filters are graded by how uniformly they trap particles. There are 2 numbers that tell how well a filter works, the beta number and the particle size. The beta is a probability that a particle of a certain size will be captured in the filter. A filter rated at 2 microns with a beta of .9 is going to trap 90% of all 2 micron particles. The beta number approaches 1.0000 very quickly for particles greater in size than the rated ones. Engine oil filters are designed to trap most particles in the 15-20 micron range. About 1/2 to 3/4 mil for you inch types. Any smaller and the filter would have too much pressure drop from in to out.

Odd thing about filters is that as they capture more particles, the spaces get smaller and they become MORE effective at trapping particles. The pressure drop across the filters will increase as this happens. When a set pressure across the filter is reached, there is a spring in the filter that gets compressed and allows the oil to flow around the filter media and go directly from pump to engine. (By the way, this happens every time you start a cold engine, if it didn't the filter media could blow out.) On modern engines, the filters almost never get to the point of clogging up -- unless maintenance has been ignored completely. Usually not changing the air filter or using a damaged air filter. Your tractor has a 2 element air filter with the housing engineered to spin off most of the big particles IIRC. Very good design.

On diesel engines the oil turns dark quickly. That is due to the presence of carbon particles or "soot" from the incomplete burning of the fuel. These particles are soft, easily stay in suspension but are so small that they pass thru the filters. You can filter them out with a by-pass filter (Amsoil sells them, others do too.)

Keeping the filter won't cause it to suddenly start spewing out a load of particles that instantly destroy the engine. It won't suddenly go into bypass mode and allow unfiltered oil free reign in the engine. In fact it will probably filter better (more smaller particles captured) and the lower viscosity oil will have a lower pressure drop moving you farther away from the point of bypass.

jb


(With all that said, I would change the filter. It's just a good habit to have, even if it is not needed.)

 

[Doc_Bob]

(With all that said, I would change the filter. It's just a good habit to have, even if it is not needed.)

Talk about having it both ways
Bob

 

[KubotaSteve]

I agree changing the filter since your changing types of oil.

I follow the manual on mine. I wouldn't think Kubota would say it is ok to do something if it is going to hurt the engine, but maybe I am young and naive or at least naive

As far as the one excuse that how much does a filter cost, if you do that with everything on the tractor it would end up being cheaper to get a new tractor . Those cylinders could have some grime in them, we should change those out. Might as well change the fuel filter even though I still have another 150 hours before it is required. Same with the hydro fluid. You start changing things like that and you would have several hundreds of dollars extra tied up every year. And if the truth be known, you could probably go beyond the manual requirements and still be ok, but a chance I'm not willing to take even though my warranty is just about gone.

 

[john_bud]

Talk about having it both ways
Bob

Chuckle...

yeah, you're right! Although, as I get older remembering if a filter was changed in the fall or spring or at all gets harder and harder. Much easier (even if not strictly needed) to change it out.

(go Packers!)

jb

 

[Soundguy]

Before you cut open the filter, did the oil give you any hint that it was dirty? or did you have to cut open the filter to really know?
Bob

When I drained the crankcase, chunks and globs came out. When i pulled the filter ( jd-B has the filter burried in the middle, under the tractor ), it came out with stuff that looke dlike dog food packed around it.

So yes.. oil looked pretty dirty..

Soundguy