'48 Fuel Selector Valve Weirdness

[gobrien]

Hi All,

I have just discovered that my fuel valve has 2 off positions, the left tank is in the left position and the right tank is in the straight ahead position. The image shows the plate that was installed.

The photo from TC170A archive shows Left = left tank, Straight Ahead = Both on, Right = right tank, Straight back = Both off which seems sensible!

Has anyone else got this kind of selector valve arrangement?

Thanks,

Gareth.

[GAHorn]

I’m suspicious your fuel valve itself has been changed-out from the original. Can you show a pic of it?

[gobrien]

Hey George,

I suspect you're correct. Looks like it might be one of these: https://www.aircraftspruce.com/catalog/ ... hutoff.php

Blurry pictures attached which may not tell you much. I have not pulled the valve so these are from my phone shoved into the hole in which the valve is located.

My initial search found nothing about 48 fuel valves, but Google now found me your earlier post about rebuilding it at viewtopic.php?f=24&t=10065#p89658.

I'm searching online but have not (yet) found a selector with the both position.

G.

[GAHorn]

There IS a way to do it...

The original valve was a brass plumbing valve made by Weatherhead and that product is still being produced (by a successor company)...just not for aircraft. I suspect someone has substituted your original with THIS valve... but didn’t modify it to keep the “Both” position.

I recently bought one to add an aux tank to my boat and it is high quality and works perfectly. It’s interior parts are changed from the old brass “cone” and fiber seals to a synthetic (plastic) cone. I like it because the synthetic has less susceptibility to “freezing” from loss of lubrication.

The new part would require you to modify it by drilling/adding a new port to the cone so that the “Both” position would work however. (And take care that you order the one with the correct sized ports.... this is made in both 1/4” and 3/8” ports. Here’s the link to the 3/8”)

https://www.amazon.com/Moeller-Fuel-Thr ... 837BQ8M1VQ

EDIT: The Spruce valve is the same item. The 1/4” valve might be more appropriate (according to Spruce, the 1/4” is for AN6 fittings): https://www.amazon.com/dp/B000MTB7Q0/re ... UTF8&psc=1

[Bruce Fenstermacher]

Wait a minute. DO NOT GET AHEAD HERE. We are talking about a '48 which had two different fuel valves, NEITHER of them being the same as found on an A or B model.

When laking about '48 fuel valves you need to talk to a '48 expert on the subject of which there are few as there are not so many '48s as there are the other models. Second best is to canvas just the '48 owners to see what they have. All the while remembering just because you found it in your airplane or someone else found it in their airplane, does not mean it cam that way from Cessna. Now if you find 5 or 6 or more is better, who have the same or something different, then you can come to a theory as to what is 'factory" and what is not.

[GAHorn]

Wait a minute. DO NOT GET AHEAD HERE. We are talking about a '48 which had two different fuel valves, NEITHER of them being the same as found on an A or B model.

When laking about '48 fuel valves you need to talk to a '48 expert on the subject of which there are few as there are not so many '48s as there are the other models. Second best is to canvas just the '48 owners to see what they have. All the while remembering just because you found it in your airplane or someone else found it in their airplane, does not mean it cam that way from Cessna. Now if you find 5 or 6 or more is better, who have the same or something different, then you can come to a theory as to what is 'factory" and what is not.

The VALVE is exactly the same for both versions (all serials) of 170 and the 170A and the 170B thru SN: 20285......PN 0413020-3.

320254D7-BA43-446D-BA99-C72DD24E229B.jpeg

380172FF-AD8A-4940-BF28-9A63279BE5BE.jpeg

.
The method of attachment of the placard, actuating mechanism, and placard assembly only is different.

[gobrien]

I opened the valve today, thankfully with no need to remove it from the aircraft. It was drilled as George described with 2 ports at 90 degrees. I mounted it in a vice in the drill press and drilled through the "left" port to form a "right" port, so it now has a tee instead of elbow inside the cone. This gives the original left = left, ahead = both, right = right, aft = off. I'm now messing about with label design.

Thanks for the info. I was happy to give it a go knowing that in the worst case a replacement valve would be $30ish. Total cost for the fix was $0. Not often the case with aviation!

Gareth.

Before.jpg

Before Drilling

After.jpg

Drilled out

Selector Label Option 1.png

Fuel Selector Label Option 2.png

[hilltop170]

That plug looks very dry. Be sure and use Fuel Lube when you reassemble it.