View Full Version : why no oil filter

Shady Brook
09-14-2002, 09:33 PM
I just purchased a Toro walkbehind, 12.5 horse, and there is no oil filter. All my other walkbehinds with 12.5's have had an oil filter. Anyone with info on this?


09-14-2002, 09:34 PM

You should be able to buy a oil filter kit for it

09-14-2002, 09:35 PM
Not all engines come with them standard. Did the one you looked at before your purchase have one? I'd talk to the dealer and see what you can work out. Good luck.

Shady Brook
09-14-2002, 10:10 PM
Oh I see, seems odd to have no filter standard. I purchased it from an individual. Any idea how much a kit would cost? Do they still make them without filter? Strange.


09-14-2002, 10:11 PM
It is well worth the money to install the kit. I had one that was without a filter and it only lasted 2 years. My others with filters still go strong.:)

09-14-2002, 10:42 PM
First thing I do before buying a mower is to make sure it has a pressurized, and filtered oil system.


09-14-2002, 11:55 PM
Oil filters are not as important as oil changes.
As an aircraft mechanic there is not much more important to us or the pilots than the health and life of these engines.
Many of these 6 cylinder piston engines can cost $ 20,000 to rebuild. An in depth study was done a few years ago comparing the wear of bearings and camshafts in engines with and without oil filters, ( yes many aircraft engines do not have oil filters ).
Guess what, the engines without oil filters had less wear !! Now I should point out that the mandated oil change interval for engines with an oil filter is 50 hours vers. 25 hours without a filter. The reason of course is that the sooner you get the "fines" out the less wear you will have, apparently the microscopic fines go right thru the filter and act as a lapping compound wearing away on the sliding parts hour after hour. I should add that we are required to cut open every oil filter we remove, and almost never find anything in them. I change my own oil quite often but seldom change my filter. BTW very, very few aircraft engines have air filters. hope this helps

Shady Brook
09-15-2002, 12:04 AM

Wow, thanks for the post, that was very enlightening. Would you suggest changing the oil twice as often as manufacturers suggest seeing how the filters may not be keeping the stuff out? I have been doing oil analysis on a PSD for a couple years, would these "fines" manifest themselves in the samples? Do you have some background in tribiology?
Thanks a bunch, and if you know of any published info on the web pertaining to the topic, I would love to read it.


09-15-2002, 12:09 AM
Heres the problem.

Many...not all...lawn mower engines without filters also do not have pressurized lubrication. I have never seen one that had a filter, and wasnt pressurized (but they probably exist)?

The reason for pressurization is because lawn mowers are often run on side hills, and wihout pressurization critical components will not get the oil they require.

09-15-2002, 12:53 AM
Hi Jay,
yes, twice as often is about when I change oil in my cars, trucks and small engines.
I do not have a background in tribiology I did take a course in it years ago. My area of expertise is in bearing vibration analysis, mostly turbine engines and propellers. we do oil analysis as well although all we are looking for is a change compared to baseline, if all of a sudden we see allot more copper or aluminum we tear it down. BTW some oil filters are great, they are bypass filters they push a small amount of oil ( 2% ) continually thru a very dense filter media like as dense as cardboard, they will filter out the fines.

Richard Martin
09-15-2002, 06:37 AM
Point, most Dixie Chopper's come from the factory with a 1 micron Amsoil bypass filter installed. I have opened a lot of my filters that come off of my engines and a few for fellow lawn guys. The only filters I have ever seen anything in is was the Amsoil filter off of my Dixie and my buddy's hydro filter off of his Exmark. The Amsoil filter had extremely small glittery particles in it and the Exmark hydro filter was just full of all kinds of junk. The Amsoil filter came off of a new engine with around 250 hours on it and the Exmark also had about that many hours on it.

09-15-2002, 09:46 AM
Jimbo you have a good point about the pressurized system on a hill. I owned a Ferris that had an un filtered un pressurized engine on it. Every time I would cut a steep hill with the oil stick side towards the downhill slope the engine would start knocking about half way thru that pass. I had to plan my cuts where I would cut with the oil dip stick side up the hill whenever possible. This usually meant going in a circular pattern instead of a back and forth pattern. Sucked. All my mowers now are pressurized and I make sure before I buy one that they are.:)

09-15-2002, 10:51 AM
to the question ,will changing the oil twice as often,exstend engine life.
in 89 i was looking at bankruptcy.
id just bought two 90 festivas ,as we lived a long way from wk. got a big financial surprize ,that i wont go into.
anyway,i determined i might not be buying new nothin for a while.
started changing the oil,the minute it got any color.using just a walmart oil that met specs. one of the cars is wrecked out back with about 200.000 on it the other is my get around to fleamarket car and i believe 227.000 last time i looked..
decide for u self . was i just lucky.:)
aint to bad for what everybody told me was a disposable car.

09-15-2002, 01:10 PM
Richard Martin,
You are correct, I should have said that in the first 100 or so hours it is even more important to get that oil out as there is all kinds of metal to metal wear and break in metal floating around. My first oil change is always at 5 hours then at 15. As I said in my second post a bypass filer can't even be compared to a regular filter when it comes to cleaning oil, they are called 1 micron but the will trap to .01 micron to some degree ( now that is small ! ). If you don't have one the only way to get it out is to change the oil.