The International Cessna^® 170 Association

In the process of removing my wheelpants, and need to order a set of replacement axle nuts. The current ones are the longer ones with the bolt hole for mounting the wheelpants, which extend too far out for mounting hub caps.

I'd like to get a set shipped BEFORE removing the old ones but not sure what size to order. I have the solid axles and cleveland wheels/brakes.

Aircraft Spruce lists the following, but I'm not sure which (if either) is the correct size:

Castle 1-1/4-16 Cessna 06-11800
Castle 1-1/2-16 Cessna 06-11900

Any help would be greatly appreciated!

Looking at the paperwork from when the solid axle / P-ponk / Cleveland mod was performed back in 1994 it refers to a MS21025-24 nut. This matches up to the parts referenced in my first post, but doesn't give me the thread size. Any way of knowing the correct thread size without pulling the old one first??

According to the B model IPC, the standard axle nut is an AN7502-24.

It looks like after the gear conversion I now have the MS21025.

According to the Spruce catalog, thread size depends on the axle:

Specification MS21025 using 4140 steel. Mild steel nuts are not acceptable for use on certificated aircraft. 1-1/4" dia. nuts for 500 x 5 axles, 1-1/2" dia. nuts for 600 x 6 axles.

I'm assuming we have the 600x6 axels????

Take one of your existing axle nuts to any machinist and have him check it with a thread gauge and micrometer.

Just measure the diameter of your axle. If it's 1 1/4 get the 06-11800 if it's 1 1/2 get the 06-11900.

Cessna axles are all 1 1/2".

The one in the a/c spruce catalog is not what you want. P/n 06-11900 is a plain castle nut. not for wheel pants. Unless you can find someone with a spare set they are willing to give you, your best bet is to get them from wentwort or some other used parts distributer. They have them at sun-n-fun for $15. If you buy them now they will run you $45 each. wentacpart@aol.com or call them at 1-800-493-6896.

I meant Wentworth

FredM wrote:The one in the a/c spruce catalog is not what you want. P/n 06-11900 is a plain castle nut. not for wheel pants.

Fred, re-read my initial post. Plain is what I want. I'm REMOVING the wheel pants.

alright, that was my brain fart for the day. I guess I'm still a little upset from the price on the ones I bought right after sun-n-fun.

AN7502 has been replaced by MS21025 in 1960 (AN7502-24 => MS21025-24)

MS21025 has been replaced by NASM21025 in 2000. (no change in part number)

MS21025-24 is a 1.5000-16 UN-3B
Jim

Anyone else have difficulty getting cotter keys (pins) back in the axels after repacking the bearings? I am speaking of putting new ones in, not reusing the old ones. In the past on one side (don't remember which) I always have a problem getting the cotter key in the hole. I am using what appears to be the correct size keys. Just wonder if maybe there is a technique I haven't tried.

170C wrote:Anyone else have difficulty getting cotter keys (pins) back in the axels after repacking the bearings? I am speaking of putting new ones in, not reusing the old ones. In the past on one side (don't remember which) I always have a problem getting the cotter key in the hole. I am using what appears to be the correct size keys. Just wonder if maybe there is a technique I haven't tried.

I bend them into the shape of a banana before I start and that helps quite a bit.

I place about a 30-degree bend in it about 1" from the split end, which can then be inserted in the first hole, and then fed thru to the second hole. I straighten the pin out after inserting it, and then bend it to lock it.
An alternative method is to place the bend about 1" from the loop/eye end, and straighten it as the bend enters the first hole.