Gas Leaking thru Fuel Cap Key Hole

[Bunkie]

I have a 1992 FJ1200 and if my tank is above 3/4 full and under hard throttle fuel with bubble up the they key hole in the fuel cap. any suggestions for fixing this problem?

Thanks

J.L.

[Pat Conlon]

Hey J.L. welcome to our site!

I also have a '92 so here's a couple of pointers:
1) Never fill your gas tank while your bike is on the center stand. Never. You WILL overfill it. Guaranteed. Always use the side stand.
2) Do the surgery on the flapper valves in your gas cap. http://www.fjowners.com/index.php?topic=2024.0
     Hint: when you take your gas cap apart to get to the valves, do it in a bucket.
That way when that little ball and spring shoots out of the lock cylinder (and they will) you won't loose them..... Don't ask....

Cheers anigo!   Pat

[andyb]

Easier way to do it is leave the cap on the bike, stuff a rag solidly into the tank opening, and surround yourself with rags so there's not far for it to go.  But the big secret?  Sweep the garage floor first, makes it much easier to find when you do drop it. 

[Bunkie]

Hey guys,

I appreciate your help, your right about the center stand, I never fill up using the center stand.

I willtake my cap apart next week and see how it works and let you know.

Thanks for the help

J.L.

[Dan Filetti]

I know this is a different bike and all, but I ALWAYS fill the Gixxer up to the very top while sitting on the bike, with it standing upright, and never had an issue with a leaking gas cap, from sloshing or any other reason.  Seems to me if Suzuki can do it, so can Yamaha. 

Thinking about it, it sure seems like a safety issue.  Are we saying it's normal for the bike to spill fuel on the ground if it falls over??!  I rather think there is, or damn well should be a problem here that is fixable.

Dan

[simi_ed]

I essentially do the same as Dan.  I always part on the centerstand, and fill to the very tippy-top.  Sometimes I even get it so full that the area above the neck gets some gas in there.  Never have I had a problem with gas overflowing the cap either.  I can't blame the PO for screwing with the cap, 'cause there isn't a PO.  Maybe everybody else's gas cap have PO'd?

Ed

[RichBaker]

I would think the flappers are already gone, the main reason they're there is so the tank can breath without letting fuel OUT..... 

[DB Cooper]

Just saw this post. I had the exact same problem on my 89 this past summer. Do the flapperectomy and the problem will disappear completely. Now I can fill the tank right to the brim and ZERO gas leaks out. The job is really easy, and it gives you a chance to lube up the lock and keyhole cover.
Kevin

[Bunkie]

Well I have disassembled my gas cap and found the problem. Previous owner cut up the large black gasket. he cut little slots following the path from the valves to the hole to the breather tube.

Is this gasket available separate?

Thanks

J.L.

[andyb]

Doesn't appear to have an individual part number that I can find.  Wonder if you'd have luck at a junkyard. 

Donors that share the same gas cap assembly (and presumably the gasket then) are:

86-93 FJ1200
86- 89 FZ600
86-88 FZ750
87-93 FZR1000
87-90 YX600 Radian
92 TDM850
93 XJ600 Seca II


I'd try using some various sealants to repair it first, personally.

[Yamifj1200]

Well I have disassembled my gas cap and found the problem. Previous owner cut up the large black gasket. he cut little slots following the path from the valves to the hole to the breather tube.

Is this gasket available separate?

Thanks

J.L.

http://cgi.ebay.com/ebaymotors/NEW-FUEL-CAP-W-2-KEYS-FZR1000-FJ1200-YZF-SRX250-RADIAN-_W0QQcmdZViewItemQQhashZitem4158be1c7fQQitemZ280661728383QQptZMotorcyclesQ5fPartsQ5fAccessories

Eric M

[Bunkie]

I removed the valve and I used Permatex on the gasket to help it seal. Filled up my bike this morning and rode it to work and no more leaks.

I would like to thank everyone that responded for your help.

Again Thanks

J.L.

[carsick]

If that is silicone it may not hold up long to gasoline. I've seen a few carbs put together with silicone and the results were hideous. At least you know the source of your leak, that's good information.