Gas cap leaks, can it be repaired?

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jbjeeps
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Gas cap leaks, can it be repaired?

Post by jbjeeps »

This is the cap on my A1. It has leaked for years. A couple of years ago I bought an aftermarket replacement. Didn't fit. Returned it. But before I did I decided to try putting two gaskets on my original cap. It fit tight and prevented leaking, but I was concerned that the tank would not vent properly, so I went back to just one gasket.

So, it still leaks. The cap fits tightly, but the gasket doesn't fit tight enough to prevent gas from sloshing out.

Since it appears to be an original style cap, I'd like to repair it if possible. Can it be repaired? Or, should I just buy another one? Can you suggest a source for a correct cap that will fit.

I just checked my post and I see that the pictures don't appear in it as I thought it would. So, highlight the photobucket address without the "img" on each end, right click and select go to image and you'll see the picture. I'll keep working on learning how to post pictures!

[/img]http://i859.photobucket.com/albums/ab15 ... de.jpg[img]

[/img]http://i859.photobucket.com/albums/ab15 ... de.jpg[img][/img]

Image These two icons must enclose the photos url as thus Image You have gotten them mixed up at each end of your URL's.

When entering a photo in tje dialog box during the typing of your post do this: Above the dialog box you click on the Image and it will appear at the end of your url.

If you try to use the Image icons at the top of the dialog box after you have typed your message they will be appear at the very end of your message. If you decided late in your message you wanted a photo up in the message then wait untill you have typed in your full message. Move the cursor to the next open line and click on the Image icon above the dialog box and it will appear at the end of your URL. Now cut and paste the entire image entry from that line up into the body of your message where you wanted it to be.

This is how your photo entries should have looked:
[img]http://1000.photodump.com /albums/ab152/jbjeeps/gascapoutside.jpg[/img]

[img]http://1000.photodump.com /albums/ab152/jbjeeps/gascapinside.jpg[/img]
I deliberately change part of your URL so it would not open a photo.

This is what happens when you follow the instructions above:
Image
Image
1953 M38A1 (His)
1963 CJ5 w/Tuxedo Park Mk III (Hers)

See you at the Old Jeep Rendezvous in Ashton, Idaho 9:00 am - Noon on the first Saturday after July 4th. All pre-1970 Jeep vehicles, military or civilian, stock or modified welcome.
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Bretto
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Post by Bretto »

Image

Image
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Bretto
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Post by Bretto »

On photobucket, at the bottom of the picture, you can click on IMG code box and it automatically copies it then paste it in your post. Its easier than copying the URL then tacking on the [IMG]
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wesk
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Post by wesk »

To answer your question, there are several causes for your sealing issue.

1-The tank is a repop and the rim of the filler pipe is formed incorrectly.

2-The locking ears on the tank's filler neck have been bent upwards.

3-The locking tabs on you fuel cap have been bent downwards.

4-The old seal is extremely worn.

Image

With the circumstances with the use of the repop cap with two seals I would suspect the filler neck on the tank is the issue.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
jbjeeps
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Post by jbjeeps »

First, I can't tell if it was Wes, Brett, or someone else who inserted the photo posting instructions into my original post, but thanks to whoever did it. I've copied them into a word doc and will save for future reference.

Second, thanks to Brett for the additional instructions.

Finally, thanks Wes for the tips. Judging by appearance the tank has been in the jeep for a long time, so I'm guessing it is not a recent repop. I'll try bending the tabs on tank and cap and see if I can get it to seal better.

Also, I don't know how that little spring like piece in the center of the cap is supposed to work. From looking at it I've been assuming that it is supposed to be attached to the plate under it and turn it to open or close a valve. But, it doesn't do that. It just spins freely. So I've just figured that maybe it had come loose and isn't operating the valve properly.

I've also sent an email to John at Midwest. Waiting to hear back about some better quality gaskets.
1953 M38A1 (His)
1963 CJ5 w/Tuxedo Park Mk III (Hers)

See you at the Old Jeep Rendezvous in Ashton, Idaho 9:00 am - Noon on the first Saturday after July 4th. All pre-1970 Jeep vehicles, military or civilian, stock or modified welcome.
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wesk
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Post by wesk »

As a group Co-owner and moderator I can access your post and edit it.

The small rectangular piece should feel resistance as you turn it to operate the small internal valve. Sounds like your best bet is a new cap. Try to get an NOS military issue cap. Ord PN 8333722 manual vent valve cap. I prefer these since they give your tank two means to vent it. Through the pressure relief vent to the air cleaner in the top of the tank and through the cap. The older caps are unvented.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
jbjeeps
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Posts: 179
Joined: Sat Jun 12, 2010 6:00 pm
Location: Idaho

Post by jbjeeps »

wesk wrote:Try to get an NOS military issue cap. Ord PN 8333722 manual vent valve cap.
Thanks for that info. I'm going to start looking for one today.
1953 M38A1 (His)
1963 CJ5 w/Tuxedo Park Mk III (Hers)

See you at the Old Jeep Rendezvous in Ashton, Idaho 9:00 am - Noon on the first Saturday after July 4th. All pre-1970 Jeep vehicles, military or civilian, stock or modified welcome.
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