Penton Owners Group

General Discussion => Penton Talk => Topic started by: Mike Hufnagel on May 20, 2010, 09:20:10 AM

Title: plastic tank stains
Post by: Mike Hufnagel on May 20, 2010, 09:20:10 AM
Is there anyway to remove the gas stains or discoloration from a plastic tank? I was thinking maybe soaking it in a bleach solution or is it there to stay?
Title: plastic tank stains
Post by: garrettccovington on May 20, 2010, 11:39:26 PM
Hey Mike
Search the message board for "painting tanks", "sealing tanks" or something like that.  I have a 1979 ktm mc80 with a white plastic paint that looks pretty bad and the members had all sorts of responses on this about 4 months ago.  I bought another tank from a member to experiment on and blah, blah haven't gotten around to it.  Anyways, you might beat me to it, but, I'm gonna jump on that project real soon and will post my results

G

72 six-day
79 KTM MC80 250
Title: plastic tank stains
Post by: Dwight Rudder on May 21, 2010, 11:38:08 PM
White Wall tire cleaner. I used to use NEW SOUTH WHITEWAL CLEANER.  Spray it on in a shady area.  Promptly spray off and don't leave it on for more than a minute. It is caustic.
Dwight
Title: plastic tank stains
Post by: kenbike on May 22, 2010, 06:48:20 AM
I have good luck with GO-JO hand cleaner getting most stains off
Title: plastic tank stains
Post by: brian larson on May 22, 2010, 01:39:35 PM
Softscrub w/ bleach works great on white plastic
Title: plastic tank stains
Post by: tofriedel on May 22, 2010, 02:12:11 PM
If you are talking about the white plastic tanks that first showed up on KTM's in 1979, the stain is from the inside out.  It is the premix that stains the plastic.  I know of no one that has successfully bleached one of these tanks and that includes riders in Europe.

The only success I have heard of was a tank that had been painted over from a POG member on this site fairly recently.  If I recall correctly, he was on the 2nd year after painting and no problems.

Others who have tried painting met with diaster, according to those individuals.

Tony
Title: plastic tank stains
Post by: rob w on May 22, 2010, 03:02:57 PM
Or a tank skin, if you're lucky enough to have this model tank.

http://www.dcvmx.com/xcart/product.php?productid=17991&cat=325&page=1
Title: plastic tank stains
Post by: Mike Hufnagel on May 24, 2010, 08:04:54 AM
Yep, thats the tank I have. I'll definatly think about that.

I was curious, as far as painting the tank goes, I would assume he sprayed it first with an adhesion promoter. But did he go through the whole primer, sealer, base coat, clear process or just promoter basecoat clear?    And if that works out good, I'll just paint the stock graphics on.
Title: plastic tank stains
Post by: 454MRW on May 24, 2010, 11:24:45 AM
If you plan on painting the tank, you should thoroughly rinse the inside with lacquer thinner several times and follow up with a dying agent like MEK or Acetone and seal the inside with Caswells first. Dave McCullough told me he had good results with a new Clarke GS-6 plastic tank using Caswells to seal the inside. If the inside of the tank is properly sealed, it will stop the fuel from migrating through the plastic and decals and paint will not bubble and peel off. I Had my 1980 KTM tank primered and painted by my local body shop with proper adheshion components, but I plan on sealing the inside with Caswells before ever putting gas in it, or it will eventually bubble and peel off. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
Title: plastic tank stains
Post by: Mike Hufnagel on May 24, 2010, 12:45:36 PM
Michael,


Is the Caswell pliable? and is there a name for their product? I went to a site that was called "caswell plating....." Is that it? Seems that they had a bunch of products.
Title: plastic tank stains
Post by: 454MRW on May 24, 2010, 12:52:34 PM
I believe it is somewhat flexible, but you will have to inquire to be sure. Dave may chime in about his most experience with his GS6 tank and how it is holding up so far. Here is a link to the Caswells tank sealer. Mike
http://www.caswellplating.com/aids/epoxygas.htm

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
Title: plastic tank stains
Post by: chicagojerry on May 24, 2010, 02:51:30 PM
caswell is NOT pliable. its an epoxy that gets hard as a rock. i used to believe that it was the way to go. but despite great pains to ensure proper application, it will still allow fumes to bleed through that will ruin a great paint job. i drain the gas from my lined and painted tanks.  mike winter, are you still satisfied with the por-15 process?    chicago jerry
Title: plastic tank stains
Post by: Mike Hufnagel on May 24, 2010, 04:03:59 PM
Sounds like it would just be easier to get the cover. I have a lot of HOK paint laying around.    Hmmmmmmm, may be I could paint the tank cover glow in the dark.
Title: plastic tank stains
Post by: 454MRW on May 24, 2010, 04:30:24 PM
Jerry,
On fiberglass tanks I still think POR-15 Clear is the way to go. I will never drain another tank. It is not for use on plastic however, but would work well on metal tanks as well. Mike
Just FYI, after ready many horror stories on the PE Suzuki and TM/RM Suzuki group sites about plastic tanks splitting and cracking because of drying out from sitting without fuel, I don't recommend completely emptying plastic tanks, originals at least. A small amount of fuel or fuel/oil mixture in the very bottom of the tank will keep the plastic from drying out and cracking when refilled, even on the shelves. NOS tanks that never even had gas in them also. I plan on soaking/submerging any of my unused Suzuki and later KTM plastic tanks in a fuel oil mixture for a few days before using them to allow both the inside and outside of the tank to contract or expand at the same rate to avoid this problem, hopefully. Nice original tanks are getting just to hard to come by. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
Title: plastic tank stains
Post by: Mike Hufnagel on May 24, 2010, 08:04:54 AM
Yep, thats the tank I have. I'll definatly think about that.

I was curious, as far as painting the tank goes, I would assume he sprayed it first with an adhesion promoter. But did he go through the whole primer, sealer, base coat, clear process or just promoter basecoat clear?    And if that works out good, I'll just paint the stock graphics on.
Title: plastic tank stains
Post by: 454MRW on May 24, 2010, 11:24:45 AM
If you plan on painting the tank, you should thoroughly rinse the inside with lacquer thinner several times and follow up with a dying agent like MEK or Acetone and seal the inside with Caswells first. Dave McCullough told me he had good results with a new Clarke GS-6 plastic tank using Caswells to seal the inside. If the inside of the tank is properly sealed, it will stop the fuel from migrating through the plastic and decals and paint will not bubble and peel off. I Had my 1980 KTM tank primered and painted by my local body shop with proper adheshion components, but I plan on sealing the inside with Caswells before ever putting gas in it, or it will eventually bubble and peel off. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
Title: plastic tank stains
Post by: Mike Hufnagel on May 24, 2010, 12:45:36 PM
Michael,


Is the Caswell pliable? and is there a name for their product? I went to a site that was called "caswell plating....." Is that it? Seems that they had a bunch of products.
Title: plastic tank stains
Post by: 454MRW on May 24, 2010, 12:52:34 PM
I believe it is somewhat flexible, but you will have to inquire to be sure. Dave may chime in about his most experience with his GS6 tank and how it is holding up so far. Here is a link to the Caswells tank sealer. Mike
http://www.caswellplating.com/aids/epoxygas.htm

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1980 KTM 175-400'S
Title: plastic tank stains
Post by: chicagojerry on May 24, 2010, 02:51:30 PM
caswell is NOT pliable. its an epoxy that gets hard as a rock. i used to believe that it was the way to go. but despite great pains to ensure proper application, it will still allow fumes to bleed through that will ruin a great paint job. i drain the gas from my lined and painted tanks.  mike winter, are you still satisfied with the por-15 process?    chicago jerry
Title: plastic tank stains
Post by: Mike Hufnagel on May 24, 2010, 04:03:59 PM
Sounds like it would just be easier to get the cover. I have a lot of HOK paint laying around.    Hmmmmmmm, may be I could paint the tank cover glow in the dark.
Title: plastic tank stains
Post by: 454MRW on May 24, 2010, 04:30:24 PM
Jerry,
On fiberglass tanks I still think POR-15 Clear is the way to go. I will never drain another tank. It is not for use on plastic however, but would work well on metal tanks as well. Mike
Just FYI, after ready many horror stories on the PE Suzuki and TM/RM Suzuki group sites about plastic tanks splitting and cracking because of drying out from sitting without fuel, I don't recommend completely emptying plastic tanks, originals at least. A small amount of fuel or fuel/oil mixture in the very bottom of the tank will keep the plastic from drying out and cracking when refilled, even on the shelves. NOS tanks that never even had gas in them also. I plan on soaking/submerging any of my unused Suzuki and later KTM plastic tanks in a fuel oil mixture for a few days before using them to allow both the inside and outside of the tank to contract or expand at the same rate to avoid this problem, hopefully. Nice original tanks are getting just to hard to come by. Mike

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