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How Not to Line a Fuel Tank

Continuing with the theme of some of my not-so-successful work on the CB350, here is the story of the repairs to and relining of my fuel tank. Yes, the piece of wood is still glued in there.

In 2009, early in the year, I once again got the old CB350 out and tried the starter--just for kicks. No click, whir--nothing. A run down to the local auto parts store and a new battery was acquired and set in place. It would now turn over, but nothing more.

Once again, off came the carbs. We were about to become thoroughly acquainted, again and again. Getting this little bike back into road readiness required all the typical stuff—cleaning carbs, new battery, cleaning carbs, new engine oil, cleaning carbs, new fork oil, cleaning carbs, new spark plugs, cleaning carbs, new tires, cleaning carbs. During this time, I peered into the tank and an obvious problem was revealed to me--rust. "No problem," I thought, "I have done this before."

Getting the gunk out was quite a challenge, but nothing me and five gallons of muriatic acid, not to mention the acid etch from the Kreem kit, couldn't overcome. And I was right; two days later I had nice gray metal showing inside the tank. What was left of the previous coating of rust was gone. A swish around of the liner prep and I was ready. Now it was time for relining and that is where things started going terribly wrong.

The instructions of the vanilla milkshake bottle of Kreem liner said you needed to pour in the liquid with all the tank holes plugged, then roll the tank around to get even coverage, then let it sit with the lid off for eight to ten minutes, recap it and roll again, let sit uncapped in a different position for eight to ten minutes, recap, and repeat.

I was smart before all this started and made a nice tight fitting plug by tapering a wooden dowel to insert in the petcock neck. I also was thoughtful enough to run some wire up into the crossover barbs to keep those from filling up with the liner liquid and becoming useless. But the big hole for filling the tank was the challenge.

I had an old rubber printing blanket from back when I worked in that industry, and so I made a round wooden cap with the blanket as a gasket to make sure nothing leaked out when I was sloshing the stuff around. A bolt through the middle of this wood and rubber disk connected to a maple bar about one inch wide and slightly wider than the mouth completed my cap. I could loosen the bolt, slide the cap on sideways, tighten the bar up on the underside of the filler, and have a leak-proof seal.

I was so excited; one more, uncomplicated step and I would be in tank nirvana, completely removing the tank as a possible suspect in my carb problem.

In goes the Kreem, on goes the cap, and slosh, slosh, slosh, around goes the white liquid. "Hey! This is not so bad." OK, sloshed enough, it was now time to uncap, and let sit that first eight or ten minutes. I was smart when I made this cap; I used a thumbscrew so no tools would be needed for capping and uncapping, but one thing I did not think through very well was how little of that screw was still in that bottom nut when loosened enough to get the cap off. A little too much unloosening and . . . off came the maple clamp bar, nut still embedded in its clever little recess I so carefully chiseled out so the nut would not rotate as I screwed or unscrewed the cap.

I could not see the clamp bar and was starting to panic. This Kreem, let's just say it is thick—think of a Elmer's Glue—thick and sticky. Anything sticking to it has a tendency to stay stuck, and the stuff dries quickly, adding to the tenacity of the hold. The nice smooth back side of the clamp bar was stuck like a suction cup to the inside of the tank.

Now, I figured the least of my worries was the paint on the tank or preserving my supply of Kreem, which now was all inside the tank. I turned the tank upside down and started shaking. At least this was performing the function of distributing the liner around the tank's inside surfaces. I heard the bar once in a while pop loose and settle somewhere else, again as tight as a barnacle on the bottom of a ship. If I could only get it near the filler hole; I could pull it out with a pair of needle nose pliers, I thought.

So I shook, and I shook, and meanwhile the white glue-like stuff was flying out of the open fill hole. It was now on my legs, my shoes, the deck by the shop, and all over the top and sides of the tank. I frantically, but lightly, tapped the upside-down tank on the wooden floorboards of the shop deck where I was working. Surely, the fairly soft wood wouldn't cause any damage to the tough metal tank.

Now I am getting desperate; the Kreem is drying and I've yet to get the bar to break loose and come anywhere near the fill hole. I figure my best hope is to at least get it up towards the front of the tank so it does not obstruct the crossovers or petcock attachment. Thump! I hear it smack against the front top of the tank and figure that is as good as it will get.

I turn my attention to the spilled Kreem all over the nice original factory green paint of the fuel tank, formerly with hardly a scratch on it. Not too bad; the stuff is still a little soft. I just get my lacquer thinner and my disposable shop towels and wipe and wipe, and I am making progress. Some of the Kreem is being stubborn, so I rub a little harder. What's that?—gray metal? Oh, rats! Damage now done, I continue to remove the white gunk along with green paint here and there.

The white remnants of the liner now gone from the outside of the tank, I can clearly see how the harmless pine deck boards have created divots in the top of the tank: a result of my tapping the tank to expel the clamp bar.

What was once a pristine tank with original paint is now a sloppily lined, scratched, and dented tank with a piece of maple and a nut coated white and glued onto the underside of the top. At least it is now coated with liner.

The tank fiasco behind me, I now turned to professional help with the motor. I could get it to run; sometimes quite well. I could actually ride it. I had not gotten my license yet, so back roads only in the groves near my brother, Tim's, house was where I justified a little road testing. Sometimes it would run like new. Unfortunately, this was not a typical ride, with most ending in a loss of power from one side of the motor and usually a slow crawl back to the house. On occasion the flatbed trailer I had for hauling lumber for my woodworking projects would come in handy to get the bike home.

I eventually got a lot of experience loading my bike on that trailer. In spite of all the practice loading and unloading the CB still things could go wrong, and one night it all went wrong in a spectacular way. (See "How Not to Load a Bike on a Trailer")

Cheers,

Road Dog

"Ride Your Own Ride"

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