Repairing a hole in the gas tank?

[Anonymous]

I have a fuel tap for my '79 550L, but it won't fit - the mounting holes are 1.75" apart on the tank, and on the petcock they are 1.5". I can't find the right part anywhere, it's discontinued and all the used ones I keep looking into are for the different model (1.5").

SO I was thinking ... I can drill a new mounting hole in the tank, and fit my fully functional used part on it - but how to cover up the original hole that I won't be using? I'm thinking Bondo won't do it for me this time, lol. So what can I use?

Am I crazy for thinking this all up, by the way? I figure that if I get a Pingel, it's gonna be almost $100 and I gotta drill into the tank anyway - and mine won't even have a reserve (I already called them). And I have NO space for a cutoff valve from a lawnmower (already tried).

Man, I have all my riding gear now, my MSF course is this weekend, and my bike is still not running (petcock is stuck on PRIme) - I gotta start thinking outside of the box and fix it! It runs so well when it doesn't have gas dripping out of the overflow tube Thanks for any help!

[SqDancerLynn1]

Look for a fuel valve from a larger GS I think you are just asking for problems by drilling the tank. Even if yours is stuck on prime it should work ok as long as your carbs are working it should not leak fuel. You could unplug the fuel line and plug the fuel tap with a short hose and bolt. when the engine is not running until you get it fixed

[Anonymous]

Yeah, I don't like the idea of drilling into my tank. Let's say that, in the future, I find the right piece - then what do I do to put it all together correctly?

However, the tap on there now is aftermarket and not quite the same shape as the original - it's not at all easy to plug it, really the tank should be raised for it. Since it won't shut off at all, the second I take the hose off a lot of gas will come out, so I need to be able to plug it off real fast.

Anyway, this is meant to be my daily driver (crazy, I know), so plugging up the tank every time I stop is not something I'm gonna wanna do too many times. It's how it is right now, but I'm not riding it yet. Thanks for the suggestion, though! And also for the tip on looking for a bigger GS's fuel tap. I'll try that, too.

My other option was: getting a longer fuel line, so I could make it go from the tap, a few inches forward of the tap (along the bottom outside edge of the tank) so I could fit the cutoff valve I bought, and be able to reach it... and then the rest of the hose would go to the carbs. Trouble is, since it's gravity fed, I think the straight, horizontal section of the new line would cause me problems. Especially since I think the tank has a slight upward tilt to it. Any thoughts on that one?

[SqDancerLynn1]

As you have figured there is not very much room to work with . My 77gs750 & 79&80gs850 all have bolt spacing of approx 1 3/4 inch like your tank

[SqDancerLynn1]

This one would probably work

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2422580046&category=35597

[SqDancerLynn1]

Another One

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2422714285&category=35597

[Anonymous]

I'm gonna try looking for those models' taps. And thanks for the links, I tried the second one as well, but the seller measured the part differently and it turns out that it is the wrong size. Ack!

I'll try those other models at ronayers.com and such. Hopefully I can get one this week that fits.

[Anonymous]

Welp, no luck at ronayers, bike bandit, or CRC ... Man, I don't have to sell this bike without ever having ridden it, just 'cause I can't find parts for it Hrmph. Back to eBay ....

[Anonymous]

what about this.... http://www.650motorcycles.com/Petcock.html

[Anonymous]

Thanks, that's a good writeup - and a much cheaper alternative to the Pingel petcock, too. I wonder what he meant by the "second on/off petcock" installed inline? Where'd he find the space for that thing?

Now, couldn't I just make my own adapter plate for the good petcock that I have, but that is a 1/4" too small? I could drill an opening in the plate that matches the tank's, then use a longer screw on one end of the plate and the petcock, so it would go all the way through to the tank, a normal-sized screw for the other end of the plate, and a short screw for the middle - the other, shorter end, of the petcock itself, to bolt it on to the adapter plate?
Thus, no drilling into the tank! Hmmm?

[Anonymous]

As long as your fuel line does not rise above the tank outlet, you will be ok no matter what tangled mess you have.