The Cessna 120-140 Association Forum

I need a oil cap with a dipstick for my C-90.

Anyone know where I can find one?

Thanks

Ben

Wag Aero and Aircraft Spruce (below) both carry them new...kinda pricey @ around $60 bucks. They are on Ebay occasionally at a better price...but pre-owned may require the extra cost of a new gasket.


DIPSTICK SHT NK 0-200 & C-90
$63.75/Each
Part# 08-04613
MFR Model# I-944-200

Mac

Thanks Mac! I had looked on Spruce and WagAero with no luck -- guess I didn't use the correct words in my search!

It doesn't get very good reviews on Spruce but I may have no choice!

Tom Julian is also going to check and see if he has one.

HOPPY New Year!

A couple of types that I've seen (pics below)...one may be more "correct" than the other, but the one with tabs that are spring-loaded (left pic) vs. fixed tabs relying on pressure from gasket (right pic) seems to seal and stay put(!) best in my experience. These are for C-85 but I expect similar are used for the C-90. (Incidentally, I tried to convince Tom Julian to just trade me his C-90 when he OH'd my C-85...but, he was intent on saving it for his own 140 ). I'd bet that Tom will find a good one for you -- plz. give him our best regards! Yep -- Hoppy New Year back to you, old friend! Hope to see y'all @ SNF. Mac

There are about 50 variants of the oil cap. First, C85s, C90s and O200s all have different "full" capacities, which is stamped on the cap itself. Second, there are 5 quart and 6 quart oil tanks. Third, there are several different lengths and angles of fill tubes. There is even at least one variant with the tube on the other side of the tank.

Continental have published a service information letter that lists the various part numbers for each engine/airframe combination, SIL00-7A.

OBTW, the one in the photo above with the fixed ears looks like a converted gas cap. Note the hole in the handle for a chain, which would have to be quite long with that dipstick, and the pop rivets...

The plain round cap with the spring loaded ears is "original" to my '46 140. I have been using the later eared type cap for the last ten years or so. I wired a small spring onto the engine mount, so that it connects to the hole in the ear. Thus, and extra step and 100% sure that the oil cap cannot come off in flight. Been there, done that.

John wrote: "OBTW, the one in the photo above with the fixed ears..."

Yes...an interesting "repair". It was included in an oil tank I bought a few years back...seller threw it in for "free" . Mac

Strange -- I am sure I replied to your photos Mac but I don't see it in this thread, so I'll try again.

Mine looks like the one on the left in your top photo but the one on the right is the one being sold on Spruce and WagAero - and that is the one that the reviews were not good - people seem to have problems with that one.

I'm hoping Tom Julian might have one.

Thanks to John Cooper and E Thomas for your replies.

Guess I need to take another look at mine and post a photograph.

Ben

There should be a part number stamped on the edge of the oil tank flange. If you can get that, it will tell you which neck your tank has. Also, the SIL lists the dipstick part number for the engine/airframe combo, assuming the engine has the tank originally specified by the airframe manufacturer.

The SIL specifies part number 649608-17 or 649608-9 for a C90 in a 120/140, depending on the sump.

All that said, sometimes you just have to go with what you've got (or can get).

Many thanks John!