The N-Series Tractor Oil Filter, Part Number 9N6731, is an intregal part of keeping your engine running smooth and clean. Dirty oil can cause premature wear and tear on internal engine parts. Keeping oil changes on your Preventative Maintenance schedule only makes sense. Check the oil level and condition each time you use the tractor before you start the engine. If it shows signs of getting dirty, plan on an oil change soon. The amount of use and external conditions will vary with each tractor so determining exact intervals is basically up to the owner, but plan on at least once or twice a year under normal use. You will want to change not only the oil, but the oil filter too. Most replacement filters today still have a wire handle to help ease the filter out of the oil filter canister. The exception I know of is that the FRAM C3 does not, but the FRAM C3P does. FRAM was the original supplier to FORD -in the pictures, the left most is an original and it has the Ford logo and FRAM Corporation listed on the decal. The decal that applies to the top lid of the oil filter housing also denotes the FRAM Corporation as well as Ford. Most filters also come with the new rubber gasket that fits under the lid. New filters use to also come with a new washer that goes under the hex bolt that clamps the lid down in place, but I have not seen this washer in packages for several years now...probably a cost cutting procedure although the unit price doubled. You might want to replace this washer also if it worn too badly as you will get leakage at this point. Just8Ns carries filters and the washers. Don't forget to check your air cleaner while you're at it. Your oil bath cup needs to be cleaned and refilled with same grade oil as you use in your engine. Go to the NTC "HOW-TO's" under lubrication to do the "Perfect Oil Change'. Here are some pictures followed by a list of oil filters and manufacturers for replacement filters for the N-Series Tractors. The right most unit is Ford Part Number CPN-6731-B, for the NAA, NAB, and Hundred Series tractors. Quart of oil and can of beer shown to give perspective...

Left to Right -
Original Ford p/n 9N6731; NOS Ford; New Holland; FRAM; NOS FORD p/n CPN-6731-B for NAA/NAB/Hundred Series Tractors.

Original & NOS -close-up View-

REPLACEMENT OIL FILTERS

Baldwin P40Big A 92010
Bosch 72127
Carquest 85010
Fleetguard LF574
Ford CPN 6731B 9N-18649; 9N-6714; 9N-2731
Ford CPN-6731-B for 53-57 tractors
Fram C-3; C-3P *C3 has no handle
Hastings Mighty M3LF-130
Luber-Finer P3
Motorcraft FL144
NAPA Gold 1010
New Holland 86546605
Puralator L20110, L20701
Texaco HSO 100
P 70 FR
Unacol 76 OF 1010
White 10575
Wix 51010
Fleetrite LFR-8574

Tim Daley(MI)

The oil filter housing cap has a large rubber gasket that fits up under the lid in a groove and it usually comes with a new filter. There is also a gasket that looks like a washer under the center bolt that clamps the lid down. The original Ford part number is O1A-18675, later changed to O1A-6749. Some may have been made of copper originally. Sometimes you need to replace it too when you do an oil change. If you get seepage from there, replace it. Don't try a regular flat washer, it won't work and it'll leak. Trust me. You use to get a new O1A6749 gasket in the filter element kit, but they were discontinued by the late 1990's. Probably a cost-savings move -reduce materials, up the price. The part number shown on package here, O1A6749, is a good number at your local CNH dealer. Just8Ns and Dennis Carpenter sell them too for around five bucks a pop. My local CNH dealer told me he has never sold one. He may not have because they do last a long time. Just remember not to overtighten center bolt. This unit is made of fiber material and measures approximately 57/64 OD x 29/64 ID x .5/64 thick.

Tim Daley(MI)

Tim:

The last time I talked to Derek about these five buck gaskets he said that they were on his list to have reproduced by an independent gasket maker. I don't know if he has made any progress on thet front.

Bob

The original 9N, 2N, and 8N oil filter cartridge and housing carried part numbers:
9N18660 - Oil Filter Housing
9N18662 - Cartridge

All Master Parts Catalogues up until at least the May 1950 one, show these part numbers. The September 1952 MPC lists the parts as:

9N6714 - Housing
9N6731 - Cartridge

Tim Daley(MI)