The International Cessna 170 Association

I was going to do this to my 170A but gave up. The plug was too messed up to allow me to remove it while installed in the airplane. I am holding off on doing it till I have to take out the fuel selector valve one day. I would think a log book entry would be fine for this one.

A question I sometimes get about this is : " Can the pipe-plug be removed and a quick-drain installed without completely draining the airplane of fuel?"

Answer: Yes. If you turn the fuel selector valve OFF... the internal check-balls will close and shut off all fuel from flowing out of the valve including the valve-drain. However, be alert to the fact that any fuel inside the valve (an ounce, perhaps) and any fuel in the gascolator which is above the valve in the 3-point stance, may "back-drain" and exit the drain. So, drain your gascolator first... and be prepared to see a few tablespoons of fuel come out of the valve when you remove the plug.

Also, do not use Teflon tape on the install. (It can/will shred and might allow particles to enter the fuel system which can plug carburetor passages.) A small "dab" of Permatex No. 2 sealant on only a couple of threads of the new drain valve is all that is required, ... and be careful not to overtighten the new drain to avoid cracking the valve body.
REmember: it's only gravity fuel pressure down there. You don't need much more than finger-tight (plus perhaps a 1/4 turn.)

OK, this thread got me curious about a drain under the fuel valve under 10B. I crawled under and found that there is no inspection port under my valve and no way to access the valve without cutting a new one! I could see the bottom of the selector but it was a good 6 inches from the nearest port. 4410B is a '55 B model (ser #26754) so shouldn't it have access? Anyone else seen this?

Mine is just like the picture in the parts manual except the belly skin plug, Number 8 in picture, has a hole for the quick drain. My serial # is 25501.

I have the #6 port next to the #8, but no #8!