C2 Fuel Tank Sending Unit O-Ring

[Joe L.]

Re: C2 Fuel Tank Sending Unit O-Ring

Joe. I have done seminars titled, "The Evils of Ethanol" for the Pittsburgh chapter. In that seminar I bring buna rubber parts and viton rubber parts. I put both in various beakers of 10% ethanol. The buna rubber parts and Hoses swell up in short order.

You know friends I have been worried about this sending tank o'ring for years but never brought it up here.
Viton rubber comes in two colors. Brownish and satin black.
Wayne said he has issues with the undersize one.
Check with McMaster Carr on the viton o'ring. If the size you want is not in their catalog (on line) they can special order it for you. Don't plan on buying one though. But whatever and sale them to our friends here. Would be a good thing for someone to do.
Back to work, JD

John-------


But, have you placed the rubber seals in gasoline with 10% ethanol and gasoline without ethanol? That would be the more meaningful test.

In any event, just because the buna-N seal might swell a bit, that does not mean that the seal would fail and leak. I have never heard of a 63-74 Corvette fuel sender seal leaking at the seal, even after long service here in California where the fuel has been 10% ethanol for many years.

The 63-74 Corvette fuel sender seal is not a standard o-ring and it's not even of any standard o-ring size I know of.

Of course, if a Viton seal of the same size and configuration as the original GM seal were available, that would definitely be the seal to use. It might not be necessary but it sure couldn't hurt to use it.

[Paul Y.]

Re: C2 Fuel Tank Sending Unit O-Ring

That's what I do too Mike and it makes them easy to install also.

[John D.]

Re: C2 Fuel Tank Sending Unit O-Ring

Hi John, A confined buna rubber o'ring will last longer than one that is not confined. Until a point. When it dries out from non use it starts cracking and is very brittle.

One would imagine that if the exact size viton o'ring was available for the sending units Wolf would have it.
Thanks Gary for the dimensions. That's a very fat o'ring. John

[John D.]

Re: C2 Fuel Tank Sending Unit O-Ring

[QUOTE=Gary Beaupre (28818);759095]JD,

Here's a photo of a NOS GM o-ring. The OD is 2.375"; ID 1.875". So the "wire" diameter is 0.250".

Gary

McMaster Carr. Viton o'ring. Dash No. 404
OD = 2.400
ID = 1.850
1/4" wire diameter
Part number: 9464K726 $7.03

As you can see friends the MC Viton o'ring is a tad larger OD and a tad smaller ID. But it's close??? Have no idea if it will work. John

[Gary B.]

Re: C2 Fuel Tank Sending Unit O-Ring

McMaster Carr. Viton o'ring. Dash No. 404
OD = 2.400
ID = 1.850
1/4" wire diameter
Part number: 9464K726 $7.03

As you can see friends the MC Viton o'ring is a tad larger OD and a tad smaller ID. But it's close??? Have no idea if it will work. John

Based on the OD and ID of the McMaster Carr o'ring, the wire diameter must be 0.275", compared to 0.250" for the GM. I don't know if any of those dimensional differences from the GM would have a bad effect. The difference seem pretty minor.

I'd love it if someone else would be willing to buy one and try it out.

Gary