The International Cessna 170 Association

I am posting a response I made to a Member who wished me to confirm which gasket I had found successful for the gascolator.
YMMV

Question:
Hi George,
Is this link still the right gasket to use on 170B with the glass bowl? I hope so, as Cessna has lost their mind at nearly $35 each.
Thanks,

(The link provided is to Aircraft Spruce PN: 05-01059, labelled a “Fuel Cap Gasket, FC2651, priced at less than $2)

Response (Don’t really want to label this as an “Answer”:

That is the one in mine and it is what I buy each year at annual inspection, PN 05-01059 (also known as FC2651, Fuel Cap gasket. It fits the gascolator, the fuel cap, and the engine oil cap.)

The dimensions for part # 05-01059 are: 1-1/2" ID, 2-1/4" OD, 1/8" Thick.

There are others which “can fit” but I don’t like them.
Examples:
06-02052, Oil Fill Cap Gasket, (also known as the TCM 533355 Oil Fill Cap Gskt),
05-11187, Gascolator Gasket, I don’t like the smaller, I.D. At 1-3/8”.
05-11191, Gascolator Gasket, I don’t like, Too Thick at 3/8”.

The Koehler K2250B gascolator used on the 170 A/B is the original. Garwin made an almost identical replacement which I mention just in the off-chance yours has been replaced. I have not tried any of these gaskets on a Garwin (and have no excuse because I actually have a NOS Garwin in my stockpile. (You never know, I may need to ransom a grandchild from China some day when they take-over the rest of aviation.)

Certainly, these options are all less expensive than Cessna Genuine Parts, which are made of a white rubber which hardens and becomes brittle after a year. The ones I replace each annual (05-01059) are still flexible and show no signs of deterioration. (Note: They claim it is not suitable for auto-gas. While I once-upon-a-time used MoGas for a short-hop of desperation ... {Disclaimer: I landed at Ol’ Gar’s place over on Toledo Bend LooEasyAnna and being the cheapskate he is, had no AvGas available... so I put in 5 gals of Shell in my right tank, took off on a short hop to Center, Tx for real AvGas, making sure to switch to that right tank to burn that MoGas out ASAP and filled up with cheap AvGas.).... I didn’t notice any difference in that gasket after that short exposure.)

Hope this helps.
George

I purchased this gascolator gasket for my next annual. I haven't installed it yet to confirm it is correct, but is another option.

https://www.ebay.com/itm/124097038714

dstates wrote:I purchased this gascolator gasket for my next annual. I haven't installed it yet to confirm it is correct, but is another option.

https://www.ebay.com/itm/124097038714

That is represented as the “official” Cessna part.... the one which becomes hard and brittle after awhile....but certainly cheaper than $35.
(See if it comes with genuine Cessna picking-tag and is not a counterfeit.)

PS: You will need TWO.

What kind of fuel drain valve is this
and where do I find one?
Thanks
Iowa

The next Q would be
are these 'butterfly' type drains still available?
Iowa

That is a Curtis Valve, PN: CCA-7450. It was used on early 172/175 aircraft. It has been superceded with CCA-7450 available from Spruce, McFarland, and others.

Did you mean to list
the Curtis valve
and the one that superseded it
with the same PN?

Thanks Mr. GAhorn!!
I'll order one up
Dave

iowa wrote:Did you mean to list
the Curtis valve
and the one that superseded it
with the same PN?

Thanks Mr. GAhorn!!
I'll order one up
Dave

It’s not a choice which I made…. It’s what the mfr’r Curtis actually did…. They simply changed the design of their 7450 valve, from a rotating tab to a twist-lock…and retained the same nomenclature. (I agree…. It’s counter to conventional practices…. surprising they didn’t assign the later design something such as 7450-1 or 7451 or 8450 or such… but, it is what it is… CCA-7450.)

Does a mechanic have to install them?
And, how are the threads prepped to prevent leakage?
Dave

You can do this yourself and just a “dab” of Permagtex #2 on the middle-thread will take care of any seepage. (DO NOT over-tighten these things….they are tapered threads and it’s only GRAVITY …no pressure exists at the valve.)
Turn your main fuel-selector valve OFF….drain the gascolator…. remove the old valve…install the new one…. turn the main fuel selector valve back ON and check for leaks.

Personally I'd use Loctite 567 thread sealant if I used anything at all. Permatex, though it shouldn't, does get hard and makes removal next time very hard. Also be a bit careful when tightening. It is easy to over tighten the valve thus squashing the "tube" by rounding it with a slipping open end wrench. It won't work well if you do.

thanks guys
dave

what is the correct O ring for a F391-72 fuel drain?
thanks
Dave

Permatex #1 hardens. Permatex #2 does not and is recommended for fuel systems. Do NOT ever use teflon tape in any fuel system.

I ended up using the original drain
with a new o-ring installed.
There was a tiny piece of red plastic stuck over the o-ring
(picture later)
Mechanic used EZTURN
He also replaced the gascolator rubber seals top and bottom
One of these cork seals was almost 'welded' on the glass!
No leak now
Ready to leave for Oshkosh in the morning
Dave