Majorhavoc's Winter Renovation: This Old Fuel Tank

[Majorhavoc]

Hi everyone:

OK, I've started work on my new winter project, my new-to-me 1990 GS500E.  Using illustrations from Marc Malagelada Duch's excellent "Carb rebuilding" article in the Gstwin.com "How To" pages, I removed the gas tank and had my first few "Uh-Oh" moments.

First, the fuel chicken seems to have been installed backwards.  Based on Malagelada Duch's illustrations, I was supposed to be able to come underneath the right side of the tank and close the chicken with a screw driver.  The illustration in the Haynes manual seems to confirm this. 



But the shut off screw on my tank is facing the left side, where it's impossible to reach while it's still on the bike.  What really confuses me is the Suzuki shop manual also seems to show the fuel shut off screw facing the left side, even though this makes absolutely no sense: there's just no way to get a screw driver up there if the shut off screw is facing left.  Can anyone tell me which way it's supposed to go or if I'm hurting anything by flipping it around? 

Also: as indicated in the photo above, one of the two fuel hose tubes came out of the fuel chicken and is currently still attached to the fuel hose.  Yes, I did loosen the clamps on both fuel hoses, but that one tube just popped out of the chicken.  I'm guessing that wasn't supposed to happen.  Anyone think I can just glue it back in with some gasket sealer and call it a day?

Next question: my first photo pretty clearly shows a pin hole in the bottom of the tank between the fuel chicken and the water drain tube.  I can stick a straightened paper clip clear into that hole as far as I dare.  After searching Gstwin and other websites, I gather plugging fuel tank holes is a non-permanent solution.   Does this mean I'm in the market for a new tank?  Any creative ideas anyone?

My third snafu may be moot if I need to buy a new tank, but I can't remove the d*mn fuel cap.  Now, to her credit, the PO did advise me she had snapped off a key in the fuel filler cap.  Her workaround was use a flat head screwdriver to open it.  Push down and twist, she advised.  As my second picture indicates, there's ample evidence to support just this kind of fuel cap abuse, but I'll be d*mned if I can open it with a screwdriver. 



Instead, I decided to remove the entire fuel cap assembly and ponder the situation from both sides.  I assumed I could just remove the 8 allen head screws surrounding the fuel cap.  To my surprise at least three of the eight appear to be purely decorative (what's with that?).  The 4 screws indicated came out in the normal way, but three others turn freely, do not back out, and clearly do not attach to anything. 

But while the screw in the 12 o'clock position turns freely and does not back out, the fuel cap collar somehow remains stubbornly affixed to fuel tank somewhere under that eighth screw.   Anyone know what Suzuki voodoo is required to remove it?

As always, many thanks in advance.

[jroymcd]

 

But while the screw in the 12 o'clock position turns freely and does not back out, the fuel cap collar somehow remains stubbornly affixed to fuel tank somewhere under that eighth screw.   Anyone know what Suzuki voodoo is required to remove it?

did you unlock and open the cap?

[Majorhavoc]

did you unlock and open the cap?

Sorry, jroymcd, I probably should have broken up my long-winded post into a couple of different topics. 

As I indicated above, I cannot open the cap because the previous owner snapped off the key inside the filler lock.  She said she could open it by inserting a flat head screwdriver and pushing down on the broken key, and then turning. 

But I can't do that (or I don't have the nerve to use enough force).  I'd like to remove that piece of key without doing any more damage.

[jroymcd]

the collar is hinged to the cap. unless you get the cap open the hinge will hold it together.

[Majorhavoc]

the collar is hinged to the cap. unless you get the cap open the hinge will hold it together.

Thank you jroymcd!  The impossibility of removing that collar any other way emboldened me with the flat head screwdriver.  I now have the cap off!

[Majorhavoc]

Success with the fuel cap!  A proverbial thorn in my side is removed.  Thank you jroymcd! 

[gsJack]

The tank shut-off screw points to the right side of the bike, your assembly is backwards in the pic.  The long tube is towards the front of the bike and is reserve.  The short tube you pulled out is the on position.

http://img.photobucket.com/albums/v443/jcp8832/GS500fuelcocks.jpg

[coll0412]

I hate to be a negative nancy, but that tank is basically toast. If you plug the leak you then, need to coat the whole tank inside since all that rust will make its way into your carbs eventually(or just plug the petcock pickup).

Figure about $50-100 for a tank, the conditions of the tank usually vary widely and so do the colors available. Yours look like the 1989-2000 style tank, and unfortunately the 01+ tanks dont work with out significant modifications.

[Majorhavoc]

Thank you gsJack.  The fuel chicken is now reversed, the way God and Suzuki intended it to be.

Coll0412 brings up a excellent point, although one I'm dreading.  Do I trash the entire tank or is there someway to repair that pin hole? 

I have to say, it doesn't even look like a rust hole.  It's perfectly round and I can see substantial metal thickness through the depth of the hole.  If I didn't know better, I'd say it was drilled.  Except there'd be absolutely no reason to drill a hole in the bottom of a gas tank, would there? 

Just curious, but there on the bottom of the tank the hole is in a location that no one would ever see.  What would prevent me from threading a small cap screw into that hole and soldering it in place?

[xanthras]

I am no expert. In fact I am new to motorcycles in general, but it seems to me that there has got to be some way to fix that hole in the tank. even if it doesnt look great, who cares as long as it doesnt leak. It's on the bottom anways. I was thinking solder as well, but im not sure how well it wil adheer. I mean, but fuelcock on the tank is held on by a couple bolts and a gasket, can you rig something up like that and then line the tank? Anyways. I have my tank off right now, I will go take a look for a strange pinhole in the spot tomorrow. I am always in favor of saving things if possible. With the rust I was fighting in my tank I searched for a while for a tank in good shape. Pickings were slim unless you were cool with one that was dented, scratched, or in as bad of shape as what you have.

[GeeP]

Majorhavoc,

The pinhole can be repaired with either acid core plumber's solder or TIG welding with proper techniques. 

The problem is, how many more weak spots are hiding just below the surface of the paint?  Unless you can do the work yourself, it is probably easier to replace the tank with a "fresh" unrusted tank.  Inspect your donor tank carefully!

I suggest coating the new tank regardless.  Ethanol laden fuel is hygroscopic i.e. it collects water from the air.  There is nothing you can do to keep the tank 100% water free.  You may not be able to see it, but it's in there!

[Majorhavoc]

The problem is, how many more weak spots are hiding just below the surface of the paint?  Unless you can do the work yourself, it is probably easier to replace the tank with a "fresh" unrusted tank.  Inspect your donor tank carefully!

You're absolutely right, GeeP.  What else is lurking in the deep recesses of an 18 year old tank?   I always seem to have more free time than money however, so doing the work myself is pretty much the general rule.

Please feel free to shoot holes in my reasoning:

Realistically, I'd most likely find a replacement tank here at gstwin.com or on eBay, not locally.  While I might be able to negotiate an inspection and return clause, that'll get expensive shipping a dicey tank back to the seller.  Then again, any seller may just as likely skip that hassle if another buyer is willing to snag it sight unseen, as is, no returns.

I'm thinking I may first attempt to braze/solder that hole and derust the tank using electrolysis.  Seems like that would be less likely than an acid etchant to disturb any other weak spots in the tank.  I already own the supplies to do that, so I'd only be out my time if I discover any additional leaks.   If it does go well however, I'll invest in some sort of tank sealant, like POR-15, cross my fingers and hope to get at least a few leak-free seasons. 

That strikes me as a reasonable monetary risk, at least before rolling the dice with another used gas tank. 
Just curious though, does anyone know for sure what is the latest model year tank that would be a drop in fit for my 1990 GS500?

[pjm204]

You can use up to a year 2000 tank with no mods to your bike, the 01+ tanks will require mods to your frame for the mounts and to your seat, possibly more.

[GeeP]

I'm thinking I may first attempt to braze/solder that hole and derust the tank using electrolysis.  Seems like that would be less likely than an acid etchant to disturb any other weak spots in the tank.  I already own the supplies to do that, so I'd only be out my time if I discover any additional leaks.   If it does go well however, I'll invest in some sort of tank sealant, like POR-15, cross my fingers and hope to get at least a few leak-free seasons. 

Your logic is sound.  It is certainly worth a shot.  You may find more than one hole, but if you can solder/braze them closed and then line the tank, you may be OK.  Depends on the condition of the inside.  Since it is mostly a time investment, there is little to lose.

My tank was fairly rusted inside with over two gallons of water lurking in there.  However, I was hole-free.  (Lucky day, I guess.)  I'm running Red Kote sealant with zero issues.

You should be able to run any tank between '89 and around 2000 when the tank shape changed significantly.   The only thing that should be different is the paint scheme.

[The Buddha]

The problem is, how many more weak spots are hiding just below the surface of the paint?  Unless you can do the work yourself, it is probably easier to replace the tank with a "fresh" unrusted tank.  Inspect your donor tank carefully!

You're absolutely right, GeeP.  What else is lurking in the deep recesses of an 18 year old tank?   I always seem to have more free time than money however, so doing the work myself is pretty much the general rule.

Please feel free to shoot holes in my reasoning:

Realistically, I'd most likely find a replacement tank here at gstwin.com or on eBay, not locally.  While I might be able to negotiate an inspection and return clause, that'll get expensive shipping a dicey tank back to the seller.  Then again, any seller may just as likely skip that hassle if another buyer is willing to snag it sight unseen, as is, no returns.

I'm thinking I may first attempt to braze/solder that hole and derust the tank using electrolysis.  Seems like that would be less likely than an acid etchant to disturb any other weak spots in the tank.  I already own the supplies to do that, so I'd only be out my time if I discover any additional leaks.   If it does go well however, I'll invest in some sort of tank sealant, like POR-15, cross my fingers and hope to get at least a few leak-free seasons. 

That strikes me as a reasonable monetary risk, at least before rolling the dice with another used gas tank. 
Just curious though, does anyone know for sure what is the latest model year tank that would be a drop in fit for my 1990 GS500?

I have been able to seal and do stuff with tanks. However it depends on how bad your leak is. This is one extreme.

http://picasaweb.google.com/srinath.the.man/TankDeDenting#

I can remove crap pockets if that part is shot, or do other things. Then weld it all shut coat it and what not.

These things will all cost you, figure 60-70 for a cut+weld+undent and figure 50-60 for a coating. That does not include crap pocket repair/removal.

I wont be able to coat till weather get warmer. So I guess I could trade you a tank that is coated etc etc for yours. But its shiny black powdercoated and I'd like 50 for that too. Essentially it be like 175 and your tank for a near perfect black powdercoated tank that has been coated on the inside. I'd like to know what exactly is wrong with your tank too. I will need to know what needs to be done to your tank to get it to where these other tanks are. No dents, no bondo is what I would like.

Oh, I have a red tank as well. Its also powdercoated red. nearly the same color as yours. Or ... whatever color the early 90's GS red was. Not sure what color yours is.
Cool.
Buddha.

[The Buddha]

The problem is, how many more weak spots are hiding just below the surface of the paint?  Unless you can do the work yourself, it is probably easier to replace the tank with a "fresh" unrusted tank.  Inspect your donor tank carefully!

You're absolutely right, GeeP.  What else is lurking in the deep recesses of an 18 year old tank?   I always seem to have more free time than money however, so doing the work myself is pretty much the general rule.

Please feel free to shoot holes in my reasoning:

Realistically, I'd most likely find a replacement tank here at gstwin.com or on eBay, not locally.  While I might be able to negotiate an inspection and return clause, that'll get expensive shipping a dicey tank back to the seller.  Then again, any seller may just as likely skip that hassle if another buyer is willing to snag it sight unseen, as is, no returns.

I'm thinking I may first attempt to braze/solder that hole and derust the tank using electrolysis.  Seems like that would be less likely than an acid etchant to disturb any other weak spots in the tank.  I already own the supplies to do that, so I'd only be out my time if I discover any additional leaks.   If it does go well however, I'll invest in some sort of tank sealant, like POR-15, cross my fingers and hope to get at least a few leak-free seasons. 

That strikes me as a reasonable monetary risk, at least before rolling the dice with another used gas tank. 
Just curious though, does anyone know for sure what is the latest model year tank that would be a drop in fit for my 1990 GS500?

Actually electrolysis is not right at all.
Anyone who has done chrome plating knows, electrolysis is line of sight. You will electrolyse crap pockets the least and everywhere else the most.
Now your leak is where ? crap pocket ? or along a weld, more than likely you wont touch that at all.
Acid etch is usually pretty in consequential on un rusted metal, and its actually more severe on areas that had more rust and the crevices where stuff collects. Its more like where access is difficult is where it gets cleaned up the best.
Cool.
Buddha.

[The Buddha]

OK screw it all ...
I should read all the posts before posting. Not just look at the first 1 line and post away.
If that hole in the middle by the fuel tap is your only hole in the tank, yes a weld - do not braze, weld up with tig torch, then acid treat and coat and run the tank, it would as good as any I sell if you coat right - Forget it ... this tank is likely to live a 100 years if you coat and dont crash the bike.
Cool.