Oil Wieght in Air Cleaner

Before the weather turned cold here in Wisconsin I changed the oil in a JD 3010. It was not expected to run in the winter months so I put the standard JD 15W40 in both the crankcase and air cleaner.

Well, after the temperatures dropped a little it had to be moved in the shed it was sitting. It flooded up, no choking.

I got to thinking that maybe the air cleaner oil was too heavy for that application/temperatures. In talking to a fellow JD enthusiast that had a 3010 gas, he had the same issue and went to 5W in the air cleaner.

Have others had this same experience? Is 5W the correct weight for winter? Can 5W, or whatever thinner oil, be used all year long in the air cleaner? Is there any performance (air cleaning effectiveness) difference between dino and synthetic oils for this application?

Thanks.

Paul

Bet there are going to be a lot of opinions on this one. The oil is supposed to "wet" the air and any dust in it so yes go for the thinner oil in cold weather.

The operators manual for older tractors say to use the same wt. that you put in the engine, so that would be 10w. Now that many people use 14-40 year around you should probably put something lighter in it in cold weather, although the air is usually pretty clean in winter, unless your grinding feed. The oil in the air cleaner never warms up either, it stays as cold as the air.

30 weight always worked good for me year around.

I agree, there could be a wide range of opinions on this subject. Check your owner's manual.

My 3020 owner's manual engine oil and air cleaner requirements are:

Gas & LP-gas
above 90F, SAE 30 or 20W-40
32F to 90F, 20W or 10W-30
-10F to +32F, 10W or 10W-30
below -10F, 5W or 5W-20

Diesel
above 32F, SAE 30 or 20W-40
-10F to +32F, 10W or 10W-30
below -10F, 5W or 5W-20

Yeah, 15W-40 could be too thick for below freezing temps. You can save the oil in it now and use it next spring.

I use 15-40 diesel oil in the air cleaner and the engine of my 4020 gasser "Ingrid" in northern North Dakota where it gets colder than -20?F with no issues. YAMMV.

Several years ago I got to thinking about the function of the air cleaner and getting the oil up to the breather fins is what traps the dirt. So I went with the cheapest ATF I could find. Thought I would use quite a bit but to my surprise hardly tell the difference in consumption. Right or wrong that's what I did and why.

Hello 2510Paul,

Same oil as in the pan, single W oil only though,

Guido.

Seems I recall a recent discussion on here about oil bath air cleaners.

Some designs have the tube extending below the top of the oil level, some stop just above.

If the design is the type that the tube is in the oil, I could see how that would be very restrictive in cold weather. Not only restrictive, but ineffective as there will be no "bubbling" action, just a glob of thick oil pushed aside enough to let air through.

I don't see where using thinner oil would hurt, as long as it stayed in there. Maybe something like the new synthetic 0w 20 would work, just keep a close watch on it.

I use 15-40 but pull warm air through air cleaner and it has so far worked even down to zero.

"Some designs have the tube extending below the top of the oil level, some stop just above. "

Not that I'm calling total "bull" on that second part, but I have never seen an oil bath air cleaner where "some stop just above".

If that were true, and the engine was never run "fast" there'd be no oil carried up into the mesh and no "washing/filtering" action.

Yeah, I'm gonna call "bull" on that!

Oops. I've run 15-40 in all of the old tractors all of these years. And one of them grinds feed every couple weeks or so. Don't tell the old tractors around here.

Wikipedia says:

Oil bath

An oil bath air cleaner consists of a sump containing a pool of oil, and an insert which is filled with fibre, mesh, foam, or another coarse filter media. When the cleaner is assembled, the media-containing body of the insert sits a short distance above the surface of the oil pool. The rim of the insert overlaps the rim of the sump. This arrangement forms a labyrinthine path through which the air must travel in a series of U-turns: up through the gap between the rims of the insert and the sump, down through the gap between the outer wall of the insert and the inner wall of the sump, and up through the filter media in the body of the insert. This U-turn takes the air at high velocity across the surface of the oil pool. Larger and heavier dust and dirt particles in the air cannot make the turn due to their inertia, so they fall into the oil and settle to the bottom of the base bowl. Lighter and smaller particles are trapped by the filtration media in the insert, which is wetted by oil droplets aspirated there into by normal airflow.

Oil bath air cleaners were very widely used in automotive and small engine applications until the widespread industry adoption of the paper filter in the early 1960s. Such cleaners are still used in off-road equipment where very high levels of dust are encountered, for oil bath air cleaners can sequester a great deal of dirt relative to their overall size without loss of filtration efficiency or airflow. However, the liquid oil makes cleaning and servicing such air cleaners messy and inconvenient, they must be relatively large to avoid excessive restriction at high airflow rates, and they tend to increase exhaust emissions of unburned hydrocarbons due to oil aspiration when used on spark-ignition engines.


And this...
Oil Bath Design

I've never changed the oil bath oil for winter. We don't have much dust to deal with in the winter time. I'll use hytran oil year round in the air cleaner. Usually good second hand oil drained from the newer tractors. It looks clean so its good enough for me.

Standard recommendation is to use the same oil in the air cleaner as in the crankcase, based on expected temperatures. You don't say how cold it was in your shed, but 15W-40 should be OK down to 0 degrees F. If the oil is thin enough for the engine to crank, it should not be restricting the intake enough to cause a problem.

You say it "flooded up". Do you mean gas poured out of the carb? That's not necessarily due to a restricted intake.

By "5W", I assume you mean a multi-grade oil, such as 5W-30, not straight-weight SAE 5 oil. (I don't even know where you can get straight SAE 5 motor oil.) I've had problems starting my tractor in sub-zero temperatures (~ -20F) with 15W-40, but 10W-30 seems to work fine. I suggest you stick to using the same oil in the air cleaner and crankcase; if the oil is stiff enough to cause intake restriction, it's probably not circulating through the cold engine very well, either. 10W-30, 5W-30 or 10W-40 should all be fine.