Models: ALL, Years: ALL

Does your fuel filter fill with red particles or even worse your carburator jets are blocked with them?

Look into your tank through the filler neck and it will most likely look like this or worse:

Bingo! You just have detected the most time consuming repair on a Pinz unless you can afford to spend the money for a new tank. The bubbles you can see in the picture are the red lining which is supposed to protect the inside of the tank from rust. It seems that this lining has problems with some of the additives in modern gasohol.

Well, we assume that you have more time then money and want to fix it yourself. First you have to remove the tank. Drain as much gas as you can through the drainage hole at the bottom of your tank. Support the tank with a hydraulic floor jack or other means and open all screws holding the tank (you may want to remove the stone guard towards the front tire first). Let the tank slowly drop a bit and open all fuel hose and filler neck clamps. Remove the tank completely.

Now to the time consuming part of the job. You have to find a paint stripper which attacks the red lining in the tank, preferably one which can be washed out with water as the ones you have to remove with paint thinner are usually quite thick and difficult to remove again.
Make plugs for all holes from rubber or wood (NO plastic -except PE- as the stripper will eat them too) and plug them all except for the filler neck hole. Fill about 2l (1/2g) of the stripper into the tank and plug the filler neck hole. Let the tank sit on one side for at least 4h, then turn it to the next side and let it sit another 4h. Continue until it sat for 4h on all sides (7). Carefully open the filler neck plug and throw 1-2 handful of gravel or smaller nuts or other sharp objects into the tank. If you have access to a shaker (as used to mix paint) the next step is easy, otherwise it’s time consuming and a lot of work.. Shake the tank on all sides for 1 to 2h (now, that’s a good exercise!) or until you are completely worn out. As longer and as better you shake as better the old liner will be removed! The task is to get it completely off, difficult to check due to the baffles inside the tank.
Once you think it’s clean carefully open the filler neck plug again and look into the tank with a strong flashlight. Do you see all bare metal (maybe some rust too)? Great, this part is done! If not and there are still flakes of the old liner on the metal plug the filler hole again and shake, SHAKE!
If everything looks fine empty the tank and wash it out. Due to the baffles it may take several attempts to get the sharp objects out from behind the metal plates.

The best results for a new liner have been reported with a product called U.S. Standard Tank Sealer from www.por15.com but other liners may work too

First wash the tank thoroughly with Marine Clean (an intense cleaner), then pour Metal Ready into the tank (etches the metal and removes rust), plug the holes again and let it sit for 1/2h on each side again. Then empty the tank again (the Metal Ready is reusable!) remove all plugs and wash it out. Dry the tank as best as you can. If you blow compressed air through the tank it will dry faster! Let the tank sit and dry for at least 24h in a warm and dry place.

Once dry plug all holes again except the filler hole and pour the right amount of tank sealer into the tank and plug the filler hole. Turn the tank in all directions several times then let it rest on one side for ~10mins. Turn the tank in all directions again and let it sit on another side for another 10mins. Repeat this until it has sat twice on all sides. If you open the filler plug for the rest times on all sides but the top one the lining will already start to cure a bit and generate a thicker layer. Once you are satisfied with your coating drain the excess por15 off the tank and remove all plugs.
Caution! Make sure that no sealer makes it into the thread of the tank drain plug!!!!

Let the tank sealer cure for at least 24h before you install the tank again. If you blow air through the tank it cures a bit faster but don’t use compressed air as it will “move” the liner.

As the tank is already removed it may be a good time to trash all the old fuel hoses and clamps and replace them with new ones and stainless clamps! Place the tank on the floor jack and lift it until the hoses can be fitted and clamped in place. Then lift the tank up until the mounting holes match and secure it with its bolts (didn’t you want to replace them with stainless ones?). Don’t over tighten the bolts!

Remark: if your filler neck also shows signs of age it’s the best time to coat it while the tank is off. The liner there is usually white and can be removed with MEK (wear a respirator!). Once removed spray it with Metal Ready, wash it and use the excess liner from the tank to brush it 2-3 times with the liner.

Compiled from several emails and newsgroup postings