Gas cap numbers?

[RICH MUISE]

You should be good at 7/16, Kerby. I measured mine at the widest part of the cam/sloped lip, just before the stop, and got .407 from the inside step, which is .042 deep on mine, so adding those together gets to .449. 7/16 is .4375, so pretty close to what you got. That cap should work fine for you. I also measured the cap, and at the bottom of the ears to the seal is .410, so the numbers work out good.

I'm glad you asked me to do this...I discovered what may have been causing the small leak with my nice chrome locking cap...look at the outer ring where the seal contacts the neck. Up top next to the notch, almost in the shadows, you'll see a little deformaty in the metal. It's like a little dimple sticking out.

[Wirenut]

Thank you Rich, I appreciate your measuring that. I know it will fit, no more trial caps. I'm glad you found the imperfection.  I'll look at mine a bit closer. Best Regards my friend.

[KYBlueOval]

the gates number for the s/w, ranchero is 31640.this one is a shallow cam.the newest listing i have says it fits full size fords,merc and t-bird for 1970.also have a mcquay-norris number dgf 40.i was a partsman in the 90's and have ford and jobber parts books,the oldest going back to the 30's.here is a picture from the gates jobber data guide showing the spex on the 2 gas caps in question.hope this helps

Thanks for the Gates number 31640. I ordered one from a Amazon seller. Should be here soon. In the mean time, I went to the Gates website and put the 31640 number in and asked for the application. Although our '57 Fords are not listed, they do list this 31640 as being the correct cap for '58 Edsel Bermuda Wagons, '58 Edsel Roundup Wagons and '58,'59 &'60  Edsel Villager Wagons. It's worth noting that there were no '57 or '58 Mercury's listed either.
This all leads me to this question...........is the gas tank and filler pipe and gas cap on '57 Wagons and Rancheros the same as the tanks, filler pipes and gas caps on Edsels and Mercury Wagons? My guess is they are the same, but it is just a guess. Those of you with Edsels and Mercury's hopefully have the answer.
Thanks
John

[canadian_ranchero]

the 31640 is listed for 54-58 and 61-63 merc s/w.the gates book i have does not list the edsel

[KYBlueOval]

the 31640 is listed for 54-58 and 61-63 merc s/w.the gates book i have does not list the edsel

Thanks. I guess it is safe to say that the Edsels, Mercurys and Ford Station Wagons are the same. I wonder why Gates does not recognize they are all the same.  I sent Gates a message today asking if the Ford, Mercury and Edsel wagon gas caps were the same. Their answer was that they did not have a listing for '57 Ford Station Wagons and that their gas caps are made by Stant.
I received my 31640 Gates cap a little while ago. It looks identical to the original I have. It also confirms that the Gates gas cap is made by Stant, as it has the Stant "S" stamped in the center.

[Wirenut]

Got my gas cap Saturday and it fits, thanks Rich for starting the thread and sharing the information and part number.

[RICH MUISE]

Glad it worked out.
I went back and reread the entire thread, curious how it got to 3 pages on just a gas cap, and I've got to correct my very first post where I stated "I found an ebay seller......". What I should have said, and was surprised I didn't, was........... "there was a thread going on in the 52-59 Ford Hamb club about gas caps and one of the members there posted an ebay link....".
Totally his and their doing....I just brought it here.
Also...in rereading the thread, I picked up on something important DJ posted on his first reply. I had totally missed what he said the first time I read it...the fact that the G31 cap did NOT tighten on the Del Rio neck. He, I think, was wondering out loud if that was because the Del Rio needed a venting cap. Could it be he is correct, and to keep all caps the same to simplify and eliminate a posible dangerous situation by offering two caps, they opted to keep just one cap, but alter the neck on the wagons, Rancheros,etc. so that cap wouldn't tighten ?
OR...more likely, I think, was the idea to make the necks different so only the correct cap would fit properly.

[Limey57]

It's posts like this that really make this site what it is!  I didn't know where to start trying to find a gas-cap, I was resigning myself to having to use one of those awful emergency plastic push in caps, but after reading through all of this I'm now FAR wiser (just maybe not smarter!!!).

[Limey57]

.......plenty for sale on EBay but how on earth do some justify $92 to post one to England??  Found someone who'll post for a more reasonable $20!

[RICH MUISE]

That's a huge difference!
Just to make sure we've got our facts straight......
DJ: on your Del Rio wagon, is it the oem tank or an aftermarket?
Clusterbuster: What model '57 do you have that the tank's neck is too 'thin', like DJ's wagon? I was assuming it was a Custom or Fairlane, but realized I couldn't remember for sure.

[djfordmanjack]

Rich, it was exactly what I was thinking in my mind. I didn't even buy the G31 for using it on the 57wagon, it just came in a lot of NOS caps. and I will make use of it later on other cars. My tank and filler neck are original to the 57  Del Rio wagon and the G31 cap is loose. I was exactly thinking the same as you, if they used a different neck to make sure that you had a vented cap on the (non vented) wagon and Ranchero tank (filler necks). I would be interested in what Gary ( Limey) bought for a cap for his Ranchero and if it fits ?!

[RICH MUISE]

Thanks, and now we have to wonder if some of the aftermarket manufactures are unaware there is suppose to be two different filler necks and use the same tooling for both.

[canadian_ranchero]

if you look at the spex page i posted you will see the 31640 is a shallow cam and the 31631 has a deeper/longer cam.that would make the 31631 loose on a s/w filler neck