Hello and question about fuel tank.

Hello everyone,
I am new to this forum and while I am reasonably mechanically inclined, I do not know everything. As many of you know, the fuel tanks on these bikes can be a problem once rust begins to invade the tank and there doesn't seem to be many aftermarket tanks to replace the original. I bought a 82 650 maxim and the inside of the tank looks ok. There is some rust and there is some particles shaking around inside when I shake it and I have read about the various methods of cleaning the inside. My tank however has a couple small leaks right at the bottom rear where moisture probably accumulated and rusted slightly around the seam. I have not made up my mind as to my plans for this bike. Part of me wants to keep it mostly original and part of me wants to make a scrambler out of it and I might need or want a seca style tank of which there are some aftermarket tanks out there. The problem besides the leaks is that this bike has not run in over ten years. I am cleaning the carbs as we speak and my immediate goal is to try and get it started first. Sorry this is long winded. My questions are a few. One, I am thinking about cleaning the original tank and getting the seam welded to stop the leaks. Is this a viable option and does anyone know how much it might cost to have a welder weld the seam? Two, just to see if I can get it started, how can I rig up a temporary gas tank? Can I rig up a plastic gas can, install some tubing to the carbs and see if it will run? If anyone knows of an article or video they can share a link to I would appreciate it. I don't want to go on a spending spree until I know it will run. I put some Marvel Mystery Oil in each cylinder and let it soak and the motor does turn. There are many issues that I will possibly ask you about in the future but for now if it's not to much to clean and weld the tank, I may use it to try and start it up or go with a temporary rigged tank. sorry about the long post and thanks for any help. Joe

 

the best thing you can do is work the motor first, clean the carbs check the valve shims then see if it starts
I use an old lawn mower tank for my aux fuel tank easy enough to find and works well. put a filter on the fuel line and a cheap petcock.

ohm out the ignition system to see if it is in spec. clean any connectors you take apart and a little silicon on them when reconnecting
there are safety switches and relays that may need attention to get the starter cranking

 

Lawnmower fuel tank. Great idea. Thanks so much.

 

I have a suziki carb rebuild manual I can upload for you if you want it covers the mikuni carbs your working on with a few differances

 

I spent a lot of time getting my old 81 xj550 seca running this summer. Sent carbs to Matt Wiley - Moto services in Arizona. He rebuilt all 4 for $350. Absolutely perfect job and great guy also. I Did many other mechanical fixes, mainly rubber type stuff. Brake rebuilds, tires, carb boots, brake hoses,valve clearance etc.

Anyway put it all together and ran like crap. No power. Turns out one of coils was bad. Only two plugs firing. The plug caps had lots of corrosion also and might have caused the coil to fail I think.

Anyway, after coils and caps replaced, bike ran perfect. Only had to adjust idle speed. My point is check all cylinders for spark before you get carbs back in.

I had lots of rust in tank also. No leaks luckily. I cleaned it best I could and installed the kn 81-0221 gas filter for insurance. Very small but flows well. Bike has been running strong all summer.

Keith

 

Thanks but I have the original service manual. I'm pretty much done with the carbs now. I just need a fuel tank hack to try and start it. I don't want to buy a tank until I am sure it will start and there isn't any major engine damage done. Appreciate the offer though.

 

I did a basic carb cleaning. As I mentioned above, the thing hasn't run in over 10 years. I have no idea what to expect. Until I know that the engine isn't completely shot, I am keeping this cheap. Carbs done, next will be to empty the oil and pull the pan to make sure there isn't pieces of metal in the pan, adjust the timing chain, replace plugs, buy a battery and try to start it. If it starts and runs even poorly, I can make a decision based on what I see when it is running. If it doesn't start, there are steps to take to diagnose what the problem could be. I bought the thing for $350 so even if the engine is shot, I can possibly part it out and recoup my money. I was just looking for a temporary fuel tank hack to use when the time comes to see if it will start. Thanks.