My First Post - Fuel Valve No Strainer

[jefffromwr]

This being my first post, I will introduce myself as a new GS650G owner. Found an '82 on CL and bought it. Now I am digging into the issues.

The previous owner reported it being cold blooded and hard to start. He said he had removed and cleaned the carbs. He also said that there was no rust in the tank. The tank was full, so I had to take him at his word.

I decided to begin working on the slow starts by check fuel delivery and removed the tank and fuel valve. I am attaching a photo, but there was no gas screen/filter. The valve had a lot of black particles in it. I am assuming rust.

IMAG1202.jpg

I would appreciate any insites on my best options. I've read a couple threads that suggest that replacing the valve is the best option, but they were a few years old. I obviously need a best option for cleaning the tank out too. I am willing to do the work myself, but any experienced users with first (or second) hand opinions are welcome to give me opinions on the practice amity of doing this all on my own.

Many Thanks,

Jeff

[tom203]

Another 650? The chinese must be making replicas. Your pic shows a petcock with no vacuum diaphragm- did you remove it? See attached link for pic of what it should look like and where to get new one for $60. Don't fiddle with old unit- there will be plenty of other stuff to do. Can you tank a pic of inside gas tank area below filler? Maybe the rust ain't bad and flushing it will save it.

http://www.georgefixs.com/brand-new-suzuki-gs300-gs450-gs550-gs650-gs750-gs850-gs1000-gs1100-petcock/

Edit: put little faith in previous owner's work

[jefffromwr]

Another 650? The chinese must be making replicas. Your pic shows a petcock with no vacuum diaphragm- did you remove it? See attached link for pic of what it should look like and where to get new one for $60. Don't fiddle with old unit- there will be plenty of other stuff to do. Can you tank a pic of inside gas tank area below filler? Maybe the rust ain't bad and flushing it will save it.

http://www.georgefixs.com/brand-new-suzuki-gs300-gs450-gs550-gs650-gs750-gs850-gs1000-gs1100-petcock/

Edit: put little faith in previous owner's work

I took the petcock apart and do have the diaphragm etc. I'll try to get a photo of the inside of the tank and send it.

Thanks for the quick response!

[jefffromwr]

This is a pretty sorry picture of the inside of the tank. My phones camera leaves a lot to be desired.

I do see some rust and pitting. There is more of the black granular stuff I found in the petcock.

Thanks again!

[tkent02]

That's not rust. Got a better picture?

[jefffromwr]

That's not rust. Got a better picture?

Sorry, that's the best I can do with the camera I have. It looks a lot like coffee grounds to me. I'd guess flakes of paint, but the interior isn't painted. Also wondering about the missing screen and if it accounts for part of the debris.

[Big T]

Dump the black stuff out onto some paper towels and take a picture

The screen will be white

maybe a failed tank liner?

[jefffromwr]

I ended up taking the tank down to a local repair shop. Their assessment was that it is dirt and junk. Nothing more. I am moving on to cleaning it out with vinegar.

Thanks again!

Jeff

[hannibal]

Don't leave the vinegar in too long. It will eat through the rusty metal and open up holes. I learned this the hard way.

[adam]

Hey if the rust is to bad you could always do a sealer just to make sure. I used this and it seamed to work very well.

http://www.jegs.com/i/KBS+Coatings/1...FYkCaQod-4gHig

It was a little more than say Kreme or other brands but it is a reputable system. I also used it on a 67 t bird I helped restore, haven't had any problems with it yet.

[jefffromwr]

Adam,

Thanks, but after using the vinegar, the crud is gone. Unfortunately I have a thin layer of orange rust. I followed Youtube instruction and used distilled water to rinse. I let it dry and now I have the layer of rust.

Anyone with experience here?

Thanks again!

[JTGS850GL]

What you have is flash rust. You can use a mild phosphoric acid solution to remove the flash rust and it will not flash rust again. The phosphoric acid will convert the rust pickle the metal. Fill the tank with fuel and you should be good to go.

[jefffromwr]

Thanks JTGS850GL!

[jefffromwr]

Hey all,

Well, I finally have collected everything; petcock with filter, replacement gaskets for the tank openings and the phosphoric acid.

I am trying to give myself a reasonable chance at getting this right and so I would appreciate any input on the following questions.

Considering the time since my last post, do I need to start from the beginning and use vinegar? Even if I don't go back down that route, I will have flash rust to deal with, so I need a better idea of the strength of the mild acid wash. I am assuming I need to cut it with water. I purchased the standard stuff from Home Depot, but there are no basic recipes included for various applications of the acid. After I use it, is there a best (or better) practice for cleaning the areas of the tank where the gaskets and cap go? Again I am assuming that the rubber isn't impervious to acid and since area between the gaskets and tank won't get coverage from gas, I will need to clean them. Finally, is the acid solution a swish and empty affair, or do I need to partially fill and periodically rotate the tank?

Thanks so much. I can't imagine what a mess I could get into without the kind contributions of forum members.

Regards,

Jeff

[geol]

Leave the vinegar alone. Put the phosphoric acid in a solution. Use no more than a quart, pout it in the tank and fill with water. Make sure all tank openings are plugged and swish it around some. Let the tank sit and look in the fuel cap opening to see when the rust turns black. Once it is black, drain, rinse the tank with water, install it and fill it with gas asap. The flash rust happened because the tank is plain steel and rusts almost immediately if left bare. It probably isn't a bad idea to coat the tank if you want to take this on as it will fix this issue, more or less for good unless you buy the wrong tank coating system. Lots of info on this site regarding which works best. The main thing if coating is patience as most cause you to have to turn the tank over for a long period to get the coating distributed evenly; most are two part epoxy-type stuff.