Etching and Sealing a gas tank

A big thanks to Cougar for his excellent work on this article. ETCHING the 6 gal RSV tank

First of all this Job Sucks.

I had purchased my 2K mm RSV last year

with only 5k on it. You would think that the

tank would not be rusty inside of it. (WRONG)

The Previous Owner apparently never topped his

tank off during our very cold winters in Iowa!

That was one thing that I always did on my past

bikes and never had a problem with RUST!

So this is how I went about doing this project

if you ever decide or have to do it.

Here is a picture of my first Filter change about 4 months

Before the ETCH Process http://www.venturerider.org/kreem/thumbnails/1.jpg http://www.venturerider.org/kreem/thumbnails/2.jpg

http://www.venturerider.org/kreem/thumbnails/3.jpg http://www.venturerider.org/kreem/thumbnails/4.jpg http://www.venturerider.org/kreem/thumbnails/5.jpg

#1- Drained all of the fuel

#2- Remove tank

#3- I brought the tank down to my local car wash put my

Quarters in and flushed the tank out for about 5 Min's.

BOY did a lot of rust pour out then! I figured that I had

Over a full cup of RUST in my tank from the start.

#4- Remove tank and place it on a towel up-side down

#5- Remove the Sender

(most likely it will be rusty) http://www.venturerider.org/kreem/thumbnails/6.jpg

Mine was always reading (NOT FULL) every time I filled

it up.... should have been my first sign! So I order a new

one at Yamaha the part # is 4XY-85752-00 and the cost is around $56.00 .

#6- Take that old sending unit and HACK it up!

with a dermal and a pair of cutters http://www.venturerider.org/kreem/thumbnails/7.jpg what you want to end up with is this

http://www.venturerider.org/kreem/thumbnails/8.jpg this will be your first (PLUG)

Then you will place that part (the old sender) over

the hole http://www.venturerider.org/kreem/thumbnails/9.jpg and bolt it on!

#7- Now remove the fuel pet-cock and make a plate and bolt that on

with the same screws that hold the pet-cock on. Use some gasket

sealer or make a rubber gasket.. http://www.venturerider.org/kreem/thumbnails/10.jpg http://www.venturerider.org/kreem/thumbnails/11.jpg

NOTE::: DO NOT USE DUCT-TAPE (it will NOT work)

Now that all the EASY stuff is done! http://www.venturerider.org/kreem/thumbnails/12.jpg

OK the FUN PART! , I used product called KREEM You will probably hear horror story's about the product , but I have always had pretty good luck with it.. Its far better then paying $1200 for a new tank. or I guess you could eBay one for about $125 and have it painted.

What I did was WAX the tank real well, then I put a good

amount of VASELINE all over the tank.. this will save your

paint job. as it worked excellent for my project!

(when all done with the project I went back to the car wash and washed

the VASELINE all off with the high power soap and water)

THE RSV Tank took TWO bottles of KREEM.

My results are awesome and the Kreem Stuck Real well

I also bought a minnow battery power pump at Wally-World

for about 6 bucks and had the air line in the tank for about 3 days or so.

Another NOTE: after I took off the Plastic and the Bib. there was

also RUST around the top part of the tank where stuff bolts onto,

I used some Auto Touch-Up Paint to stop the rust after a I cleaned

those parts off to be rust free again. the bib and plastic Cover will

cover the mismatched color anyways.

---------- these are some other people that have done this -----

Coating Your Gas Tank Interior:

The kit is a 3 solution (bottles) program. Before you start, first degrease the tank with your own dish washing soap. I used regular liquid dish soap, then did it again with Simple Green. You would be amazed at the amount of rust and crap I got out of the tank just by doing this.

This is a good time to drill out the breather hole in the tank neck. With all the gas fumes gone, I increased that little hole to almost ¼ inch and added another one, opposite, on the other side.

This was discussed here many times.

Now the hard part is to seal up the tank for the acid bath. These chemicals are NOT paint friendly and you have to be extremely careful using them.

You cannot pour them in and out without getting some on the tank. The tank has to be covered with plastic & plastic tape to prevent contact. The pickup tube hole is easily plugged by taking a small piece of metal and drilling a couple of holes to line up with the ones in the tank. A rubber gasket under the metal plate does the trick. The hard one is the tank filler hole.

I tried a few different methods with not great results. I even used an automotive expansion plug in the hole. Everything leaked. Finally, I took a double layer of heavy plastic bag and pushed in into the hole. Then I forced the gas cap in while holding the key open and slid it into position, released the key and wiggled the cap it to set the locking prongs.

That worked.

I was ready to start the kit. The first part is an acid bath that I kept in for about 24 hours with agitation every once in a while. Tilting it this way and that got the solution to all interior parts. There was still rust in the filler hole area, so I used an old toothbrush to get that clean.

Dumping this out revealed a lot more gunk. This stuff must have grown in there because I was very careful with what went into that tank. A good rinsing out and draining was next. There was still a lot of water sloshing around in the tank even after through draining from both holes. I used an aspirator and some oxygen tubing to suck the rest of the water out.

The next bottle is a conditioner/water remover. This was sloshed all around the tank to absorb the excess water and coat it with solvent to receive the tank coating. A couple of minutes of this and it was dumped and aspirated out.

Finally, the white paint like, Kreem coating was dumped in the tank, and the tank sealed. The tank was rolled every direction possible to get this stuff all over in insides. The tank was opened up and aired per the instructions and then re-agitated for another coat. The Kreem was dumped back into it’s original container (about half came out). There was still some liquid inside and the tank was rolled around every hour and placed in a different position so the coating wouldn't puddle in one place. After a day of drying, this process of coating the tank with the white liquid was done a second time. After a good drying, the holes can be cleaned out and the petcock reinstalled. I have a nice clean white interior now.

These tanks are bare metal.

The only manufactures that coat their tanks are Harley and BMW. Go figure.

Chuck C.

----- MORE-----

I have used Kreem w/ v good success, but as with most things in life, the preparation is the most important part. Four important fine points to consider:

#1 - Tank preparation:

The inside of the tank should be completely free and clear of all loose particulate (i.e rust, dirt and sludge). Even more importantly, it must be totally devoid of any and all hydrophobic (oily) substances, including any and all traces of gasoline, oil and grease. To achieve this, I drop two 8" lengths of medium size linked chain into the tank, then pour a small bottle of liquid degreaser full strength in and slosh vigorously with all the openings capped off. Do this good and long, and don't forget to invert the tank and get all of the surfaces degreased up around the filler neck, as well as the very top of the inside of the tank.

Next, add about 1/2 gallon of the hottest water you can get, and add this to the degreaser and the chains still in the tank (don't pour out the degreaser yet... leave it in there) and slosh it around again. The degreaser will emulsify (turn milky white) and hold all of the oils in suspension... this is a good thing. After you are quite certain that you've degreased all surfaces... give it one more slosh just for good luck. Then, pour out the entire mixture and fish out the two chains. After that, pour about a TBSP of hand dishwasher detergent and about a gallon of very hot water into the tank and slosh thoroughly (note: you can use automatic dishwasher detergent here, but as it is formulated to be very low sudsing, it is more difficult to determine when all of the residue has been removed via rinsing.) If you degreased properly in the last step, this wash should produce mongo volumes of suds... also a good thing, as suds are an indication (in this case) that the oily residues (read gasoline) have been successfully removed. Follow by as many cold water rinses as necessary to remove all traces of detergent.

Only now are you ready to phosphate etch the metal in the tank with Kreem kit bottle #1 (Phosphoric acid). Although the directions call for a specific quantity of hot water to be added to the quantity of acid provided, IMO it is better to have a FULL tank of etching solution than to have the exact proportion of acid to water. In the case of an XS650 tank, this amounts to adding perhaps 3.75 gallons of HOT water (3.25 for early tanks) to the acid, as opposed to 2.5 gallons, which (I believe) is the quantity specified in the directions. Again, as in the degreasing step, it is vitally important to have the etching/phosphating solution come in intimate contact with ALL inside surfaces of the tank, including up and around the filler neck. Seal all the tank openings and slosh that bad boy around, but after you're through sloshing, don't forget to slightly crack open the stopper on the filler neck, or the hydrogen gas evolved from the chemical process will blow it out of the hole and across the room, probably splattering phosphoric acid solution on your nice new paint job (don't ask).

#2 - Dewatering:

The small bottle of solvent (Kreem kit bottle #2) is MEK (a close cousin to acetone) and is a very good water remover. After you have thoroughly rinsed the phosphate solution out of the tank, it is time to get things dried up and ready for the polymer coating step. Actually, "Dry" may be a bad word to use here, because the intention is NOT to get the inside of the tank dry from all liquid residue, but rather only to get all WATER residue out. The inside of the tank will still be wet when you are done with this step, but it will be wet with MEK, which is perfectly fine, because that is the same solvent which is used in the polymer to keep it dissolved. Caution: do not dawdle after using the dewatering solvent. IMMEDIATELY go on to the polymer coating step. If you wait too long before you go to the next step, you may "flash rust" the inside of the tank, which will require starting over. If the inside surface of the tank begins to physically dry out, you're taking too long and are in danger of forming flash rust. Get you ass movin' boy!

#3 - Coating:

Conservatively speaking, there is enough polymer in bottle #3 to do AT LEAST two (probably three) XS650 tanks. What this means is that, unless you have two or three tanks prepped all at once, you are going to not use all of the polymer provided in the kit. You must remove the excess polymer from the tank that you are working on. Follow the instruction very carefully here, rolling the tank around for a few minutes, then letting it set on one side, followed by rolling around again and letting it set on another side, repeating until you are secure in the fact that all interior surfaces have been thoroughly coated. After that, you MUST pour out any remaining polymer, or you will have a puddling problem. Even after you pour out the excess, you must continue the process of rolling the tank and then letting it set on alternating sides, while the remainder of the polymer still in the tank forms a non-moving film.

#4 - Drying/curing time:

Probably the one most crucial mistake leading to premature failure of Kreem coatings (after improper degreasing) is insufficient drying or curing time before putting the tank back into service. After you are satisfied that the majority of the polymer in the tank has skinned over, follow this procedure:

Remove all stoppers from all openings, both top and bottom (filler & petcock holes).

Turn the tank upside down (preferably on a hot surface like your black asphalt driveway at noon in July (January if you're in Oz) and block it in place so the filler neck is facing vertically straight down. Then, rig up a small air pump and hose and stick the hose into the tank from the underside through the filler opening, being careful not to allow the hose to touch the inside surfaces. An air pump from a fish tank fits this bill perfectly. Turn on the pump and let the forced air dispel the vapors from inside the tank, which will aide drying and curing. After a few hours, you will no longer be able to smell vapors coming from the tank. It is then safe to move the tank, but DO NOT use the tank yet. Move the whole rig up into your hot, oven-like attic and allow the air pump to run for another two days minimum, with the hose still in the tank. One day is probably enough, which is why I always do it for about a week just to be sure. It pays to watch the weather and plan to Kreem the tank on a day that is going to be sunny, hot and dry, if at all possible.

If you add the above tips to the (already pretty good) instructions included with the three part Kreem kit, you will end up with a well sealed, carefree fuel tank for many years to come. Good luck!

Bill in Yardley, PA

I really hope nobody has to go through this Yucky

Job,. but at least now some will have some idea of

what will take place if ever you need to do this job!

Jeff