plastic tank sealant?

[OhioTed]

Has anyone found a fuel tank sealant that does the job in plastic tanks?  I'm not trying to seal a leak, though.  Rather, this is just to try to protect the tank stickers from bubbling up as the result of fuel vapors leaching through.

[3putt]

Ted, Dave McCullough just sealed a Plastic Tank last week with Caswells and the hope of preventing just the thing you are asking about.   I suspect he won't have a good answer for you for several months or so, but we will update you at VMD.  If you try something else, please let us know your results.    Regards,   Nelson

[OhioTed]

Thanks skads, Nelson.  What is "Caswell's", and where do it get it?

[slvrbrdfxr]

Ted,
The product my dad talked about in his post is the Caswells epoxy based fuel tank sealant. It did a very nice job on the plastic tank and I suspect I'll have no trouble keeping decals on it now that it's sealed. The kit cost about $45 shipped and comes with enough to seal two five gallon tanks. There were others who posted on this same subject awhile back so you might want to do a search for Caswells on the site for more info. Below is a link to the website where I bought the the sealant kit. Took about 10 days to arrive. Good luck !!
Dave McCullough

http://www.caswellplating.com/index.html

[thrownchain]

You can also use the site:  //www.britishfasteners.com , there is a link there also. [guy is about 45 mins from me in Lyons NY]

[tofriedel]

What type of plastic tanks are we talking about, the injection molded KTM tanks of 1981 and later vintage, or some other plastic tanks?

According to Caswell's "Bonds to almost anything except polyethylene."

I am not sure what plastic material was used to mold the injection or blow molded plastic tanks back in the day.

Tony

[slvrbrdfxr]

Tony,
The plastic tank I sealed with the Caswells was a brand new Windsor tank that I bought from Al B for my 77 250 GS6. My OEM tank sprang a leak at the reunion ride last year so I plan to use the plastic one when riding events from now on. I will eventually repair and seal the OEM tank with the Caswells also. I would think the sealant will work on any plastic tank as long as you prepare the inner surface as they recommend. Maybe someone else will reply that has used the sealant on some other tanks.
Dave

[OhioTed]

The bike in this case is a Can-Am.  I have no idea what kind of plastic it is.

http://i303.photobucket.com/albums/nn155/OhioTed/Can-Amtoe-mail2.jpg

[OhioTed]

It has been suggested to me that POR15 can serve as a fuel tank sealer, when then need is as described here, as opposed to leak-sealant.  Anyone have any idea if this is an effective method?

[454MRW]

I think it would make an excellent interior tank sealer in a fiberglass tank if the tank was prepped correctly, but it will not stick to plastic, and is not designed to be used on plastic, so use on a newer KTM tank is pretty much out of the question. I have used it for years on Corvette repair and restoration and apply it after dipping it into a plastic mixing cup or old butter dish. Once dried you can peel it right out of the plastic dish in one piece. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S

[OhioTed]

Thank you, Mike.  I did not know about that aspect of POR15.  My only experience with the product was on the undercarriage of my old Mustang, where of course it worked as advertised.  Sure appreciate the insight.

[454MRW]

I just recently coated the inside of a metal Honda XL175 tank with Red-Kote, after cleaning the rust out with Evaporust, and although the layer of Red-Kote adhered pretty well to the plastic mixing cup that I used to mix it in while thinning it with 20% MEK, I was still able to peel out the layer of Red-Kote in one complete piece. It adhered better than the POR-15, and I might try it myself in a 1980 KTM tank that I have to see if it works any better on the type of plastic used on the KTM tank.
The POR-15 would "pop" loose if you sqeezed the mixing cup flat, while the Red-Kote would not, not matter how hard you sqeezed on the mixing cup and I had to actually use my fingernail to peel the edge loose in order to get it started and then peel it out of the cup in one piece. The POR-15 would usually crack and come out in several pieces, and it was a much thicker coating. The website instructions for Red-Kote mentions thinning it using 20% MEK to greatly reduce drying time and allowing for 2 thin coats in a tank which would greatly increase the probability of success in my opinion, even though the website states that it does not stick well to plastic tanks or plastic parts inside of tanks. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S