A little trouble....(Updated With Pics)

[coll0412]

So I finally got to my reserve on the bike, only to have it basically loose all power.

At frst I thought that maybe I had switched the hoses when putting the tank back on, but I was able to limp it homw to the gas station only to find that I could only fill it with 2.5 gallons

Luckily I am only a few blocks down and mananged to limp it home.

After a little snooping, I think I determined the cause, when I drained some fuel from the float bowles it didn't really have the potent smell of gas, infact rather water downed, and after a little more draining out came some onrange tinted fuel, with like what appeares to be rust(looks more like red mold).


So how did water get into my tank, we have had some serious stormes out here over the previous weekend, and the bike was out in the rain. Is it possible that the seal around the filler cap is leaking?

What is the best way to get all this out of there, besides draining the tank, any tricks?

Should I also take apart the carbs and clean them or since I caught this early enough will they be okay....


Anyone else ever had this problem?

[Kerry]

Minnesota has some pretty cold winters, right?  The water in the fuel system is probably a result of condensation right out of the air in the tank.  (Unless you were very careful to store the bike with a FULL tank of gas.)

Since we're talking rust (and not just varnish) shine a light in the tank and see what the bottom looks like.  (Use a flashlight ... NOT a lighter!  )  If it's pretty rusty, you might want to fix that problem before cleaning the carbs TOO well, since the source of the rust will still be there.

If it were me, I would definitely take a look inside the carbs.  You know that there's some rust on the bottom of the float bowls, but a good cleaning will also take care of any varnish that may have formed in the jets, etc.

[GeeP]

I copied from this thread:

http://gstwins.com/gsboard/index.php?topic=26466.0

You'll have to take the tank off and wash it out.  Water will continue to lurk in the tank if you don't flush it.  I would also give the carbs a cleanout.  If it was CLEAR water I would leave them alone, but rusty water always has crap in it.

Here's what you do:

Go down to Wal Mart and buy the following:

8 quarts of 92% rubbing alcohol
2 cans of carb cleaner
1 roll of paper towels

You will also need:

1 metric socket set to remove the tail plastics and tank
1 #2 phillips screwdriver
1 standard screwdriver
1 plastic hammer (to drive out emulsion tube)
1 pair needle nose pliers (to fiddle with the control cables)
1 pair safety glasses
1 pair chemical gloves
1 container to hold the contaminated gas
1 large LIGHT COLORED dishwashing bowl or similar


Method:

Turn the petcock off and mark the location of the petcock hoses.  Remove the fuel line to the carburetors and put it in the container.  Put your petcock in the "prime" position and drain all the fuel.

Remove the tail plastics and then remove the tank.  Turn your petcock to the "off" position.  Now dump TWO bottles of rubbing alcohol into the tank.  Close the lid and shake like hell in all directions for several minutes.  The alcohol will combine with the water, even in tiny crevices, and remove it from the tank.  It will also dislodge whatever crap is within the tank so you can flush it out.

After shaking for several minutes open the cap, turn the tank upside-down and shake out all the alcohol into the dishwashing bowl.  You'll see water and crap.  Dump the bowl where you don't mind killing the grass and repeat three more times.  By the third load the alcohol should be coming out clean.  On the last batch, turn the petcock to "prime" and allow some alcohol to run though the lines and petcock.

Your tank should now be spotless inside.  Put it aside, now we get to do the carbs.  I hope you have a Clymer's manual available, if it's your first time you'll likely be needing it.

Remove the carbs from the engine.  Disassemble them ONE AT A TIME on your kitchen table.  This will prevent mixing parts, and will also make it easier to find whatever you drop.  Start by removing the float bowl, vacuum cap, and slide.

Look for crap in the bottom of the float bowl.  Next, remove the float, float needle, main jet, and idle jet.  Remove the emulsion tube from the housing, being careful not to break the slide guide.  Trick:  Unscrew the main jet all the way, then re-thread it about a half-turn.  Tap on it with a plastic hammer to remove the emulsion tube.  Hold the carburetor in your hand, DO NOT place it on a table such that the slide guide will contact the table as the emulsion tube is unseated.  You may have to gently remove the emulsion tube from the slide guide once you have removed the assembly from the carburetor body.

Now take out your safety glasses, chemical gloves, and carb cleaner.  Put the straw on the can and spray the hell out of every passage from both directions.  Use the whole can if necessary.

Assembly is the reverse of disassembly.  Be especially careful that the floats operate freely.  Mechanic's trick:  GENTLY shake the carburetors up and down once assembled, the floats will sometimes stick.  If you can hear them rattling they're not stuck.

Put it all back together and put a gallon of gas in it.  Pull your spark plugs to check for fouling.  If fouled, you can get by if you brush them thoroughly with a brass brush.  Reinstall and fire it up.  Remember:  You'll need to put the petcock in the "prime" position to start it the first time.

You should be able to get this thing running tonight, in time your test tomorrow.   

Keep the thing out of the rain, and keep the tank full to prevent condensation from forming in the tank.  If your cap leaks, go to the local sign shop and have them cut out a circle of magnetic sign material in your favorite color.  Make it about 3" larger than the gas cap.  Just slap that on there to keep the rain out.

[coll0412]

SO I have found the problem, water in the tank....the drain hose was plugged...prorbably from my last removal of the tank 
So once the length of the tube was full it just ran into the gas cap(which must leak)

I found this out when I pulled of the tank, and the drain hose unkinked and rusty water ran out.

I drained most of the tank, and there was a very visible line of this soft spongy looking rust sitting on the bottom of the tank.

Here is a pic what it looked like when it drained out....(yeah I had to use my oil drain pan because the gas can was full by the time I emptied the tank into it)





So threw some gas back into it, and shook it around and most of it came out.

There was still a thin film of the rust so a made a little contraption to scrub it off



And now the tank looks like this on the bottom




Put it all back together and she runs like new again, what is intresting is how the rust was just like floating ontop of the metal and could be wiped right off


I opened the carbs up also, and the float bowl and all the internal were nice and clean still so i got lucky there

[Kerry]

SO I have found the problem, water in the tank....the drain hose was plugged [...] once the length of the tube was full it just ran into the gas cap(which must leak)

I found this out when I pulled of the tank, and the drain hose unkinked and rusty water ran out.[...]

Good one for the ol' GS500 mental archive!  I never would have thought of that possibility.