Red Vented Fuel Cap Check valve

How to keep the Cessna 170 flying and airworthy.

Moderators: GAHorn, Karl Towle, Bruce Fenstermacher

Post Reply
User avatar
Jim Collins
Posts: 68
Joined: Tue Oct 17, 2017 1:34 pm

Red Vented Fuel Cap Check valve

Post by Jim Collins »

Hey All,

I have two question that I really did try to search the web and this web site to find the answers to but failed.

1) On the Red Vented Fuel Caps, there is a red silicone check valve that has broken and fallen into the tank which is causing fuel to come out the top of the cap and onto my wing. What is the part number for this check valve and where can I buy more?? I can buy the whole fuel cap but they are $180 now which seams too high for what you get.

2) Is there a cleaver way to find and remove the broken check valve part that is swimming around in my fuel tank just waiting to block off my fuel supply??

Thanks much

Jim Collins C170B N2488D

P.S. It was so nice to meet and talk with all the Cessna 170 owners that I came across at Oshkosh
User avatar
n2582d
Posts: 2808
Joined: Mon Apr 29, 2002 4:58 am

Re: Red Vented Fuel Cap Check valve

Post by n2582d »

Jim,
This entry talks about the umbrella valve in the fuel caps.
Gary
User avatar
170C
Posts: 3182
Joined: Tue May 06, 2003 11:59 am

Re: Red Vented Fuel Cap Check valve

Post by 170C »

That little red umbrella piece of silicon or rubber, wondering if it floats or sinks to the bottom of your fuel tank? If it doesn't float I would drain the fuel out of the tank and look inside with a borescope to locate it. Then with one of those flexible, spring activated devices we use to retrieve dropped nuts, screws, etc I think you should be able to remove the errant item.

I'm sure there are safety precautions that will need to be used to prevent ignition of the fuel vapor in the tank. I don't know how dangerous it might be using a borescope probe in a freshly emptied fuel tank, but other members can probably give you some guidance.
OLE POKEY
170C
Director:
2012-2018
User avatar
GAHorn
Posts: 20967
Joined: Fri Apr 12, 2002 8:45 pm

Re: Red Vented Fuel Cap Check valve

Post by GAHorn »

The full feed outlet within the tank consists of a 3" long finger strainer and the little valve will not cause fuel feed problems. Leave it alone.
Buy a Salvage fuel cap.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
hilltop170
Posts: 3481
Joined: Sat May 06, 2006 6:05 pm

Re: Red Vented Fuel Cap Check valve

Post by hilltop170 »

Jim-
I have two old caps with the red silicone check valves that are both still good.

PM me your address and I’ll mail them to you.
Richard Pulley
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
User avatar
Jim Collins
Posts: 68
Joined: Tue Oct 17, 2017 1:34 pm

Re: Red Vented Fuel Cap Check valve

Post by Jim Collins »

Thank you - Gary - George - Ole Pokey (?) and Richard

Richard - I e-mailed you my address and phone number

Thanks again to all of you

Jim Collins
User avatar
Jim Collins
Posts: 68
Joined: Tue Oct 17, 2017 1:34 pm

Re: Red Vented Fuel Cap Check valve

Post by Jim Collins »

To all,
Gary had mentioned I should probably post what I had found and learned so others in the group can benefit.

1) Gary had very kindly sent me two of the fuel caps with the plastic body. I was able to take the two caps and after a little sanding, priming and painting and combining of parts, build a good working cap. Thanks Gary

2) I was also able to repair the original cap with a new umbrella valve from MiniValve part # UM145.003-544.01 made from FVMQ (Fluorosilicone) which had to be special ordered because they normally do not make these with that gas resistant material

3) I know George mentioned just to leave the old broken valve in the tank because it should not harm anything because of the finger screen in the tank. But the thought of it in there bugged me. So I drained the tank and using a camera probe I have for checking cylinders, found the broken valve and removed it with a long pair of grabbers. Luckily it was not in the rear most baffle area as that would have been close to impossible.

Thanks all

Jim Collins N2488D
User avatar
Jim Collins
Posts: 68
Joined: Tue Oct 17, 2017 1:34 pm

Re: Red Vented Fuel Cap Check valve

Post by Jim Collins »

I ment to say Richard and not Gary in the above posting. Sorry Richard
hilltop170
Posts: 3481
Joined: Sat May 06, 2006 6:05 pm

Re: Red Vented Fuel Cap Check valve

Post by hilltop170 »

No problem Jim, glad you could use them.

p.s. You can edit your own posts after they have been entered. Just hit the edit button in the top right corner of the original post and change it however you want. :)
Richard Pulley
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
adedominicis1987
Posts: 7
Joined: Sat Feb 27, 2016 11:11 pm

Re: Red Vented Fuel Cap Check valve

Post by adedominicis1987 »

Advanced auto has the Holly Carburetor accelerator pump check valve for $12.99 in a 2 pack. Looks visually to be an exact match for the umbrella valve required. part# 26-41
Post Reply