oil bath air filter capacity??

thomasinnv · August 04, 2010, 08:43:43 PM

i am going to be servicing the oil bath air cleaner soon. I have the service manual which gives the procedure, but it does not give the quantity of oil. I know the cups have fill lines on them, but how much oil do i need to buy to do the job? don't really want to run to the store for oil a quart at a time.

Madmike · August 05, 2010, 05:04:14 AM

I had heard some where that it is a 1-1/2 gallons. I need to do the same thing, let me know when you find out for sure.

kyle4501 · August 05, 2010, 06:57:11 AM

If it were me, I'd remove one & measure how much oil was needed for it - then multiply that by the number of cups.
Some here advise using the used motor oil from your last engine oil change for the filters

- but I haven't finished forming an opinion on that yet, but I'm still pondering . . .

Len Silva · August 05, 2010, 07:06:38 AM

I would hesitate to use old oil but not to use the cheapest oil I could find.

kyle4501 · August 05, 2010, 07:29:53 AM

OK, so I went & looked at the manual.
I now have an opinion concerning oil in the air filter - use only clean new oil - I may not use delo 100, but it will be 40wt & it sure as hell won't be used or dirty oil.

According to the GM manual -
Oil required is the same as used in the engine.

Service interval is every 2500 miles!

To service, remove cup, pour out oil & clean cup. Remove the mesh & clean it with solvent - let it dry (don't use compressed air) before reinstalling.

The dirty air must go thru the oil as it is making an abrupt change in direction. most of the dirt is slung out of the air into the oil. Some oil is carried by the air & the mesh traps this oil & as this oil collects in the mesh,it traps any fines that are still in the air as the oil drains back into the cup.

It is for this reason the mesh needs to be cleaned when the cups are serviced. My guess is that that doesn't happen often & is why paper elements are used today (- after you factor in the labor rate to do it right, the paper filters are cheaper if you're paying a shop to do it for you. )

How much dirt will dirty oil collect? How much will it let pass? How well will it drain back into the cup? How much dirt will it leave behind as it drains back into the cup?

FWIW, the original service manual for my Scenicruiser calls for 2 quarts in each cup & there are 4 cups. . . .

mountain goat · August 05, 2010, 10:59:00 AM

This is what I found on my 1965 PD-4106.........I had to remove the ENTIRE Air filter assembly from the bus in order to hone the right side cylinder bores for fitment of new liners. The oil in my filter "bowls" was clean as were the elements, BUT when I pulled the assembly I found 45 years of dirt and grime! It was a wonder the engine was able to get air at all. This "stuff" was caked on so thick it took 1 hour with a putty knife, 4 cans of degreaser, $10 at the local car wash to get it all cleaned up! I'll bet I scraped 15 pounds of "stuff" off of these. So just cleaning the filters and replacing the oil is NOT enough maintenance on these older buses.

kyle4501 · August 05, 2010, 11:13:38 AM

How many use heavy grease to seal the paper filter to the housing?

A filter can't filter air that isn't forced thru it.

That is one of the problems with owning an old bus - we don't know what sins it has suffered before we got it.
If the oil bath was run dry in the past, dirt would have gotten past it & the later cleaning of the elements can't undo what already got past . . . .

sweeney153 · August 05, 2010, 03:05:33 PM

The manual says

Quoteslush element up and down in bath of cleaning fluid until all oil and dirt deposits are removed

What kind of fluid do you use? Should I use a parts washer or Soap and water or something else?

Kevin

Sweeney153

mikelutestanski · August 05, 2010, 03:26:48 PM

Hello: When those units were in my bus I cleaned them with diesel or kerosene. Then reoiled with 40 weight. Mci was appprox 2.5 qts per hole. One of my friends found a paper replacemment element for the oil bath utilizing the original hardware. One paper element per hole. If you take some measurements you may be able to find the filters. Mci used to carry the kit but not now. most of those buses are gone and they dont hardly carry any 9 parts anymore.
Regards and happy bussin mike