Oil bath air filter

[Jordan Baker]

I’ve got three different Chevy oil bath air filters. I’d like to know which one is appropriate for a Cab13 C15a

The sandblasted one and the middle one are the same diameter. However the sandblasted one seems to have an extension on the bottom of the oil bath. This makes it taller. However the oil bath is still the same depth. The other difference is that the filter portion is removable allowing for cleaning out of the filter. Whereas the middle one is not removable.

[Jordan Baker]

Last couple of photos showing the middle filter.

[Owen Evans]

Jordan,

I can't speak for the 13-cab, but the one off my 11-cab C15 is the same as the one on the right (i.e. the one with the 'curved' orange AC decal). The diagram in the MB-C1 maintenance manual (Section Q - Fuel & Exhaust) suggests the 'tall' one is not correct. Assuming the diagram is accurate, of course.

Owen.

[Harry Moon]

Both of mine look like the one on the right.

[cordenj]

Hi Jordan,

Its the one with the orange label...or at least that is identical to the one on my Chev 216 in the HUP

[Bob Carriere]

Been trying to use a frame CA146 paper filter element as recommended by Harry Moon..... however...... I have now discovered that the filter assembly comes in at least two different sizes.......... mine and the five other spares I have are all 8 1/4 inches across the oil bath bowl........ above paper filter will not fit....

Grant as a very similar filter set up except that it is 9 inches across and the paper filter does fit......... 3 feet away they look the same until you measure them.

Small ones seem to be more abundant even on EBay......

Parts book shows 3 different one at 9 inches and one as 8 /34 inch.

May try to find a smaller diameter fram filter......

Any suggestions???


Question for Phil W. ..... in another posting you showed a picture of your wiring harness and you air filter bowl......... would you mind measuring the diameter of your bowl.....no rush. Thanks

Did mine shrink??????

[Grant Bowker]

Jordan's filter with the orange AC label seems to have part number 1544945 on the cover. Can the number be confirmed? I don't see it in the parts list for C15A, C60S, C60X or the earlier list covering all models C8 to CGT. Nor do I see it in the 1929-1948 master parts list.
Googling Chevrolet 1544945 didn't produce any relevant results for me either.

First, can the number be confirmed?
Second, can anyone help me to understand?

A possible explanation is that the cover to the air cleaner isn't listed separately in any of the above parts lists so the number might be the number for the cover alone.... If the cover is integral with the element this idea seems to fail as the number isn't one of the ones given for the element in the parts lists.

Bob - feel free to photo and post my cleaner along side yours and the mockup of the Fram CA146 to show the fit issue...

[Bob Carriere]

According to the Master parts Catalogue to 1951 it could be an early 50s series.......

1951 COE oil bath number of 1544981 and pass. 1544872.....
none give any dimensions.....

None of the other early 40 civilian and Maple Leaf truck parts book list more than one oil bath.....serviced by AC.... no dimensions given.

In the 1947 shop manual the truck HD oil bath is shown similar to the large deeper bowl that Jordan sand blasted........ it is almost as if a regular bowl stamping had been cut to insert/weld a strip of sheet metal to make the filtering element deeper.......more surface area to trap dirt.

????????

[Bob Carriere]

Harry is right........ the one with the decal is a larger size that would accommodate the Fram AC 146....... the middle one is what I have on my C15a and is the smaller bowl..... also the same on other 40 and 42 civilian chev trucks..... the left one recently sand blasted is the HD with the factory modified deeper bowl..... shown in a 1947 Chev truck manual..... no part number. The top lid of the larger air cleaner and the HD cleaner are probably interchangeable at 9 inches......

Hollander's interchange book does not list air cleaners.

????????

[Paul Singleton]

I know that General Motors used identification numbers on parts, particularly on interior plastic parts. These were not part numbers, but usually were close to the actual part number. I remember ordering a glove box door that was plastic and calling the dealer and saying that I have the number. The number moulded into the plastic I was told was an identification number for a subcontractor to GM, and not a part number. When I received the part the number on the door was the same format but not the same as the part number. Maybe this is where this air filter number came from.

[Lynn Eades]

Grant, just because it looks Chev is it a Chev filter?
AC stuff was made for all sorts of vehicle makes
I have not looked into this at all, but maybe it's an AC number?
Just suggesting...........

[Grant Bowker]

Agreed that it could be an AC number rather than Chevrolet. However, both are 7 digit numbers and as of 1927 (according to Wiki) "AC became a division of General Motors" so I wouldn't expect them to be issuing numbers in the same range without some type of co-ordination 10 years later. I might also have a United Motors (another component of General Motors) parts catalog around that could give a hint.
Trying to be more generic, I had searched air cleaner 1544945 without luck.... So more digging to be done.

[Bob Carriere]

For those of us with tiny little air filters it appears that CA2675 paper filter should fit........ only 2.75 inches tall and may need some elevator shoes in the form of soft foam padding to raise the lid enough for proper airflow.

Seems to be the next best thing as per the Chat room at Fram. Will have one to try out tomorrow and to post photos. Price $17 at Benson and $19 at CTC but they have to be ordered.....listed as low demand.

Another one is CA79 ...but only 2.55 inches tall.....but could stack up two for 5 inches.......


Another glitch I have encountered is that the smallish air filter (8 inches something) once properly filled with oil will also spray oil at high speed and possibly due to increased airflow from the 6 bladed fan I am using......... some GM air filters for the early 50s did have a sheet metal strip added to the leading front edge of the bowl that effectively reduced airflow into the air filter assembly.

I am planning to add some hi temp insulation to the inside of the engine cover and it would be nice to keep it reasonably clean. Passenger side is only 3/4 inch from the exhaust manifold and does get dangerously hot in the Summer time.

Cheers

Stay tuned.