Fuel Tank Sealent. Lesson learnt

[mike_of_bbg]

I used Caswell epoxy to seal my tank and did not de-rust (just once each acetone/water/alcohol rinses plus 48 hours to dry), as they say it is not necessary and in fact that light rust is beneficial for adhesion of the coating. It was less laziness than that my tank already had leaks so it was hard to keep any de-rusting solution in it. Over a year now and so far so good. I allowed the epoxy to cure at least twice as long as indicated in the instructions before adding gasoline to the tank.

The big problem with not de-rusting is that Caswell cures clear, so you can still see the rust left behind when you're looking in the tank It's a HARD shell - not rubbery at all like Kreem coats I've seen - so I can't imagine it's going to be subject to any chemical peeling.

Had I another tank to seal, well, I'd use Caswell because I have some left Otherwise I'd give POR-15 a shot if there were no leaks. With leaks present I'd definitely use Caswell again. The biggest drawback with Caswell is how viscous it is and how that makes it difficult trying to get a good, all-over coat.

[Turtleface]

In regards to the adhesive qualities of POR-15...

When I was dumping out the excess POR, whist sealing my tank, I accidentally split some onto my oil catch tray. Being an oil catch tray, and covered in assorted goos and liquids, I just left it there to dry, figuring I could just pick it up outta the oil and chuck it. I now have POR-15 stuck quite well to my catch tray. Mind you, this stuff was applied OVER a combo of oil, brake fluid, grease, and assorted thread lubricant/sealants. Some spots bubbled quite nicely, some bits didn't lift at all and sealed directly to the tray and won't come off at all. The bits that lifted and bubbled, I have messed with, and while not stuck to the tray, they are still very durable, and resist all sorts of physical attacks against them. I have no doubt that this stuff will work perfectly in a properly prepped tank, if it's able to adhere under the disgusting conditions present in my oil catch tray. I'm going to leave it there, just for giggles. Lets see how long this stuff can stand up to the abuse my catch tray goes through.

[Moki of Rancho]

I thought regular gravel would be fine for scrubbing the inside of my 850's tank. Boy, was I wrong. Turns out marble-sized pebbles can get stuck in the tapered part of the tank, and are then a total pain in the rear to extract. If I ever have to seal another tank, I'm getting those tiny aquarium rocks for sure, since I'm pretty sure those can be flushed out with water.

[Nessism]

I thought regular gravel would be fine for scrubbing the inside of my 850's tank. Boy, was I wrong. Turns out marble-sized pebbles can get stuck in the tapered part of the tank, and are then a total pain in the rear to extract. If I ever have to seal another tank, I'm getting those tiny aquarium rocks for sure, since I'm pretty sure those can be flushed out with water.

The aquarium rocks are a pain to remove. They do rinse though for the most part but the last few take some time and patients to get out - going in though the fuel sender unit hole with some tape on a stick works well.

Using larger pieces (nuts and bolts, screws, etc) to scrub the inside of the tank will leave some of the surface uncovered. The aquarium rocks are small, with sharp edges, so they get into all the folded edges and nooks and crannies inside the tank.

[spyug]

I have used Kreeme, POR and Caswell and have had good luck with them all. As mentioned, good prep and not rushing would seem to be the key.
As the monk once said, "Patience Grasshoper"

Of the 3, I think I like the Caswell product best as it covers well, does adhere to rusty bits and dries rock hard. As a bonus, it costs about the same as the others but there is enough product to do 2 tanks.

Best advice I can give would be take your time and follow the instructions closely. Once the liner cures give it 4 or 5 days to "outgas" before fuelling up and you should be fine. The Kreeme liner in my XS650 was still fine after 5 years and the Caswell in my GS at 4 years still looks as good as new.

Cheers all,
Spyug

[diesel_lv]

I take mine to a local radiator shop. They clean them chemically then seal them and stand behind their work. Cost 100.00 to do my last tank. More expensive than a kit, but no work on my part and great peace of mind.

[Nessism]

I take mine to a local radiator shop. They clean them chemically then seal them and stand behind their work. Cost 100.00 to do my last tank. More expensive than a kit, but no work on my part and great peace of mind.

I don't trust radiator shops to do that kind of work. As far as a warranty goes, unless they give you a 5+ year warranty, you won't know if it was done right.

[1_v8_merc]

The acid solution in Kreem is very good at dissolving rust chunks in any tank.
I was extremely happy how it killed the rust.

But, after I drained the tank, it was just flash-rusting WAY too fast!
I literally couldn't patch the tank back together fast enough.

The moron at the bike store sold me JUST the Acid and Cleaner product but NOT the sealant. He told me to just clean the tank, and throw gasoline in it, and the Gas would prevent the rust.....

I wanted to go back and punch the guy in the face.

I should have just sprayed some WD-40 or oil in the tank to prevent the rust, then flush it threw the petcock while pouring fresh gas in the top.

But I didn't know much about it at the time!

--------

I just dealt with the flash rust and burned it threw the engine.
After a couple fill-ups, the rust is mostly all gone now.

Not the most professional way to do it, but it worked damnit.

Never touching tank sealant though, I've just heard that Eventually it will burn off threw the engine at Some point.

[Colin Green]

Important info re tank sealers/liners

I have just been reading Classic Motorcycle Mechanics (UK Mag for 60's to 80's bikes)
and they had a very interesting article about modern fuels with comments from four oil companies re changes in properties of more modern fuels (incl seasonal differences). Quite informative with respect to the effects of standing fuel in older bikes (with venting tanks) and the effect of the introduction of bio fuel content on older (venting) machines (more water in tanks) and the nasty of nasties... what it does to tank liners .

Have scanned and inserted pages below.

[Colin Green]

[sedelen]

I tried to repair a leaky Skunk tank with Kreme in '82, didn't work for me,
continued to leak so I bought a new tank for around $200 painted, you could still get them new from Suzuki back then.

[1948man]

I'm letting a 3.5 to 1 solution of molasses sit in my tank now. I found a feed store that would sell bulk molasses for $2.50 a gallon if you bring your own container. I used aquarium rocks before the molasses to get the loose scale out. My question is how do you put the sealant (Caswell in my case) in. Do you plug the sending unit and petcock holes and pour thru the filling hole and then just roll the tank to different positions while leaving the filling hole open? Also how are you sure you have all the rocks out? I don't hear any and flushed with a water hose before the molasses. Do you use a mirror to view the nooks and crannies? Thnx Jim M

[hampshirehog]

Further to what I said in an earlier post about Petseal, I have it on very good authority that you should stop using it from now on.

My mate 'designs' petrol, amongst other petro-chemical compounds, as a job. He's tipped me off that across Europe there is a new additive going in to super-unleaded immediately and being phased in to normal unleaded that will dissolve Petseal. The old 4 star, if you can find it, will remain unaffected.

[pat]

tank sealer

most of the fuel you buy now is about 80% bio ethalene and it will eat away at your sealer , pat

[bluewool]

most of the fuel you buy now is about 80% bio ethalene and it will eat away at your sealer , pat

80% seems highly dubious; however may be true in your particular location but is definitely not the case in North America.

So I contacted POR15.

No reported issues with any of their tank liners with ethanol blended or ethylene blended fuels. Zero.