The International Cessna 170 Association

Would anyone of you know the dimensions of your 0-300 dipstick gaskets? My 0-200 dipstick gasket measures 2 1/4" OD by 1 3/8" ID.

I understand the Continental may have two different thickness' on their 0-300 gaskets, part number 300641 (thick) and 300642 (thin). My 0-200 is 1/8" thick, looking for something a tad thinner (how's that for scientific?)

If anyone has any knowledge of thier gasket dimensions or knows anything about the thick/thin thing please chime in!

Dave Sbur/Vancouver WA
C-140 driver, but maybe someday she'll grow into a 170...

Dave,

I'm not sure what a dipstick gasket is. Are you talking about the gasket between the oil tank and the case on 4-cyl Continentals (the "dipstick" being the oil pickup tube)? If you are, then since you don't YET have a 170 you may not be aware that O-300's don't have a part like that. They have a cast "oil pan" (offically known as a sump) which is rectangular in shape the runs the lenth of the bottom of the case. Go to www.geocities.com/cessna170bdriver for a better idea of what an O-300 looks like.

Good luck in your search.

Miles

Oh my! I guess that is quite different. Yup, never really looked at an 0-300 close, kinda reminds me of a Franklin. I suspect I need to look more at the Lycoming drivers, I seem to recall they have a 'dipstick' such as I'm accustomed to! Thanks for the education-

Dave,

You might try to find some sheet cork or fiber gasket material and make your own. I would suspect that those materials would come in various thicknesses, and there would be one to suit your application. George, correct me if I'm wrong, but this kind of thing would qualify as an "owner-produced" part, wouldn't it?

Miles

RG-533355 from Real Gaskets is 1/8" thick, RG-633240 is 1/16" thick. These are silicone gaskets. To get the equivalent TCM part numbers drop the "RG". These gaskets will probably be made of Nitrile rubber.

Is this the gasket under the cap for the dipstick? I assume it is and if so I seem to remember someone on a previous thread saying that gasket was the same as the gasket for the fuel tank cap. Check with George or others on this. NAPA rubber impregnated gasket material may work to make your own gasket as Miles has suggested provided it is the correct thickness.

David, what you need is 05-01059 Gasket for FUEL CAPS #2 GASKET FC2651 , priced at $1.95 each, available from Spruce, 877-477-7823:

What in the hell is the difference in the dip stick reading no matter what the thickness of any useable gasket is? If it's a matter of closing the cap: If the cap can't be closed, it's too thick. If it's loose, it's too thin.

Well, to expand a bit, the gasket on the 0-200 fits both the dipstick and the fuel cap. Some owner-produced caps we have seem to prefer a slightly thinner gasket as opposed to the 1/8th" gasket that seems 'standard'. Not knowing any better I was googling around and found a note that 0-300's have two different thickness of 'dipstick gaskets' so naturally I was interested in following up! Now you know the rest of the story-

I keep hoping my 140 will grow into a ragwing 170, you'd think with all the rain we get up here it could happen...

n2582d wrote:You might try one from real gaskets, p/n RG-533355 for $2.50. http://www.realgaskets.com/files/horizo ... ontinental

looks like this and is this thickness - -RG-533355 OIL FILLER CAP GASKET (1/8" X 2-5/16" X 1-1/2") I imagine it needs to be this thick for an effective seal.

WARNING: Do NOT use EPDM (so-called "silicone") gaskets on gascolator bowls, however. This material is NOT suitable for constant immersion in fuel or oil. It will absorb the petroleum product and warp.

If used in a gascolator it will shrink away from the outer circumference and risk the loss of all fuel supply while inflight, while the fuel runs into the slipstream at the exit-cowl.

Most "REAL" brand gaskets are of this material which should never be used with fuel.

Was thinking the same thing. Plus, there are some mogas users amongst us (for a short while longer as we can no longer find the stuff).

Standard proceedure is to soak the stuff for a week or so before using it as even when we're told it's fuelproof or suitable for fuel systems we've been disappointed. We'll stay away from the silicone stuff and search for nitrile-like stuff. An old timer told me the original Cubs used leather gaskets for their fuel caps, go figure. Amazing how sometimes the suppliers tell me it's OK to use only to find out otherwise...

David Sbur wrote:Was thinking the same thing. Plus, there are some mogas users amongst us (for a short while longer as we can no longer find the stuff).

Standard proceedure is to soak the stuff for a week or so before using it as even when we're told it's fuelproof or suitable for fuel systems we've been disappointed. We'll stay away from the silicone stuff and search for nitrile-like stuff. An old timer told me the original Cubs used leather gaskets for their fuel caps, go figure. Amazing how sometimes the suppliers tell me it's OK to use only to find out otherwise...

David,
Good post......soaking a gasket is a good idea......altho...if not put in the criteria that it is to be used......will still give a deformation......if left out to find it's own place, even if the gasket is in the correct environment will "swell"....Brad

As previously stated, properly soaking the cork is very important. Please refer to the following;

http://www.yikers.com/video_cork_soaking_snl_skit.html

gahorn wrote: Do NOT use EPDM (so-called "silicone") gaskets on gascolator bowls, however. This material is NOT suitable for constant immersion in fuel or oil.

So what do you think about Real's rocker box cover gaskets? Do they have the same problem in this application? It would seem to me that these gaskets would be in constant contact with oil here.