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Discussion Starter #1
I have been having an ongoing problem with my VN700 and fuel leaks.

When I bought the bike (an '85, the only year they made the VN700), it had a leaking fuel tank. I identified (or thought I had) the leak, it was between the mounting flange under the seat and the base of the tank itself. I filled it with JBWeld and thought the problem was fixed. Well, it was also leaking around the front left mounting flange. At this point, I got POR15 and sealed the inside of the tank. Problem solved, or so I thought again.

Well, I remounted the tank, and came home a day later to a garage full of gas smell, and the left side of the engine was damp with gasoline. I got my hands on a Clymer manual, and noted that the two petcock screws were supposed to have nylon washers on the screws. The manual says something to the effect of "do not attempt to use metal washers, they do not seal, and cause gas leaks." The previous owner did not have them on there, and I didn't know. I went looking for nylon washers, but could not find them at the Kawasaki shop, hardware stores, auto parts stores, etc. I did have some rubberized fiber gasket material, so I fashioned washers from that. I also replaced the petcock gasket (which the Kawi dealer did have in stock).

I reassembled the tank and petcock and left it on a tarp for 2 days. No leaks.
Another two days sitting on the bike. No leaks.
Last night, I bolted the tank back down and reconnected the fuel lines, and all of a sudden I'm smelling gas again.

Does this sound like a problem with the petcock? Could bolting it down to the frame be torquing the tank in such a way as to cause the leak? (When bolting it down, I did notice that the front flanges were bending slightly inward as I tightened the bolts. I thought this was normal.

Can someone suggest something? The tank is great until I bolt it down...And my wife has given me two unpalatable options...Store the bike outside or drain the fuel.

Also, does anyone know someone in Northern/Central Virginia who is good with Vulcans? I am going to need a carb job since I have not ridden the bike that much since I bought it (in June).

Thanks,
--Storm
 

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HAWK
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People have had problems with the mounting flange tabs cracking if tightened to tight. Will cause a fuel leak.
 

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storm16 said:
Also, does anyone know someone in Northern/Central Virginia who is good with Vulcans? I am going to need a carb job since I have not ridden the bike that much since I bought it (in June).


--Storm
There's a good Yamaha dealer in Frederick, MD who has always done a nice job for me. Fredericktown Yamaha - it's a family-run business, and they are very good. The service manager, Jerry, is excellent. The other option in this area is up in Hagerstown - Twigg Cycles. They're a little bit more of a fancy-pants dealership, and although they sell and service Kaws, I've not taken my bike to them ever (bought a used one from them once, and it had a significant problem). You might also post a question to the NoVa Craigslist motorcycles site and see if anyone has any recommendations - most of what I've read there has been pretty negative for the DC area.

However, before you go schlepping your gas-laden bike around (and thereby having your wife tell you that you now need to sell the car/truck), check the Vulcan Verses on this site for the use of SeaFoam to clean your carbs. It's got all kinds of reports of being a "miracle worker" on long-sitting bikes (and even new bikes that get crud in the carbs). You can get it at Pep Boys for about $6 - for the money, it's a great first shot at cleaning out the system.
 

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JB weld will disolve with repeated contact with fuel. I sealed an old 72 Galaxy car tank with it way back when and the patch held for about a year or so and then re opened. That and the JB weld doesn't flex very well so if you bent the tabs on the tank when mounting it, I would suspect that you broke the patch loose and it is leaking again.
As far as options, you can try the Weld again, drain the tank and dry it out and have the cracks welded by a shop, or replace the tank. Used tanks are on ebay all the time or you may check a motorcycle salvage yard if there is one nearby.
 

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Threre is suppose to be a rubber grommet between the ear on the tank and the frame. You can see it on the diagram at this link http://www.ronayers.com/fiche/400_0213/fuel_tank_1_2/fuel_tank_1_2.cfm?man=ka&groupid=10850&parent=10700 It is part number 92075. If this is missing then tighten down the ears will cause leaks. I this found out the hard way. Once you have found the leak the best fix is to find a good welder that can weld the crack closed. You will have to drain the tank and let it sit for a few days to make sure the fumes are out befire it can be welded on. There are also tank patch kits at your local hardware store. Either way I would drain the tank and let it sit for a few days to make sure the fumes are out. Otherwise the patch won't hold or the welder will be in for a nasty surprise.
 

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and the Adventure Cycle
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Definatly get some seafoam. And, like Fergy & Sky Rider said, probably a good idea to look for another tank. IMO, that'd be the best option.
 

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Discussion Starter #8
Crobins365 said:
There's a good Yamaha dealer in Frederick, MD who has always done a nice job for me. Fredericktown Yamaha - it's a family-run business, and they are very good. The service manager, Jerry, is excellent. The other option in this area is up in Hagerstown - Twigg Cycles. They're a little bit more of a fancy-pants dealership, and although they sell and service Kaws, I've not taken my bike to them ever (bought a used one from them once, and it had a significant problem). You might also post a question to the NoVa Craigslist motorcycles site and see if anyone has any recommendations - most of what I've read there has been pretty negative for the DC area.
Thanks for the tips. Fredneck and Hagerstown are a little far for me. I actually consider where I live "Central" Virginia. With the Northern VA traffic, Richmond is actually about the same amount of time though further in miles. So hopefully I will run across a shade-tree mechanic who specializes in Vulcans, or at least Kawasakis.

--Storm
 
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