Are modern petrol tank liners any good?

general_piffle

general_piffle

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Location
London/Hampshire
I think I’m getting crud from the tank of the 750 GT that’s fine enough to pass through the filters and end up in the carbs.

This in mind I’m considering getting the petrol tank lined with one of those new ethanol proof liners.

Has anyone done this before? Is it worth it, are the tank liners any good?

Thanks.
 
Clean the tank out and rinse it with a phosphate solution to keep rust away.
The only indication for liners are pinholes because you don't want to do the job properly which involves changing panels.
Paul
 
Used a product called Slosh here in the UK not so long ago which is still available ........ a Chinese copy Suzuki GS125 had a tank that leaked although only a few years old ........

You have to make sure the tank interior is bone dry and follow the instructions to the letter .

Worked well ........ which is more than can be said for the rest of the bike ................
 
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general_piffle said:
I think I’m getting crud from the tank of the 750 GT that’s fine enough to pass through the filters and end up in the carbs.

This in mind I’m considering getting the petrol tank lined with one of those new ethanol proof liners.

Has anyone done this before? Is it worth it, are the tank liners any good?

Thanks.
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Just clean the tank properly. Any tank liner should be a last resort to perforations or grp protection.

If its just rusty, then clean it. Doesn't need rotations, amps or mechanical means. Amongst others, citric acid will make it spotless in a few days, sodium bicarbonate will neutralise it, meths will dry out the water preventing flash rusting. Then oil it or fill it.

That's my limited but personal recent experience with 2 rusty tanks ( my fault for neglecting them).

Rob
 

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As above. Even if newer liners are “better” I still wouldn’t trust them to last more than a few years, just delaying the inevitable permanent repair.
 
Like a good paint job, it's all in the prep. Jota Rob's prep sounds like it will do the job. I used Por15 that was sitting unused in can 10 years. Did the 3c with it 5 years ago. Still perfect in there.
 
I have done dozens of tanks. For rust, by far, the best solution I have used is citric acid and either washing soda (sodium carbonate) or bicarbonate of soda - baking soda at a Ph level of 4. I have done every other method - vinegar, muriatic/phosphoric acid, electrolysis. They may be faster, or cheaper $$$, but not better. The citric acid and soda mix will chew rust for breakfast and not give off noxious gas or create problems with paint or skin - within reason.

For me, any liner is a last resort. I had to use liner -Caswell - on my Norton tank, due to pinholes. It's holding after a couple of years, but I'm leery it will outlast me. I just did my 3C tank. It was horrible inside, but I realized it was mainly old fuel - crusty carbon looking like rust. Berryman's B12 chemtool and gasoline mix got it clean, but not perfect. So after the Berrymans, I used some citric acid/soda in it, with a non-agressive (rounded edges) chain shaken around inside to get things agitated. The inside is perfect now. It appears that the tank is galvanized inside, I'm not sure how that can be, but that's what it looks like. Absolutely spotless after cleaning, and it was nasty at the start of my job.

After the acid wash, I flush with my garden hose, then fill the tank with hot water and a lot of baking soda or sodium carbonate to neutralize And shake, baby, shake. Next I drain and put a clean microfiber rag in the filler cap, and shake (more) to absorb water. Then I pour a pint of isopropyl alcohol in the tank to really absorb the water, heat it with a hair dryer, drain and do the same microfiber rag in the filler cap & shake thing. Then more drying with the hair dryer. Finally, I either spray fogging oil inside or dump a pint of ATF inside and swish it around. Only then am I satisfied that it is 100% clean and ready for fuel.
 
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If it fails its a bloody nightmare to remove. Many years ago, I used CREAME before it was well known just how shitty that stuff was on a rusty Triumph tank; it kept blocking up jets with rust dust. That ended up requiring the bottom of the tank to be cut off, a big clean out, and it was welded back on. A complete waste of time, money and required a new paint job. Learned a good lesson.
 
I had to have a GTL tank with leaking front seams repaired last year, it was cut open and welded from inside before welding back together.

If a tank is just rusty inside and not leaking, and the rust was removed with the above methods of citric acid etc, how would things fair if one of the modern AC51 type protectors was applied; would they just disappear on first taste of fuel?
 
Re using the chain to rattle around inside the tank, others use drywall screws. I’ve had amazing results using aquarium gravel in roughly 5mm size to clean out the rust. Works brilliantly and easy to remove from the tank. Cheap as well😂
Tom
 
rocketonarail said:
Used a product called Slosh here in the UK not so long ago which is still available ........ a Chinese copy Suzuki GS125 had a tank that leaked although only a few years old ........

You have to make sure the tank interior is bone dry and follow the instructions to the letter .

Worked well ........ which is more than can be said for the rest of the bike ................
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I've also successfully used slosh about 5 years and 20k miles ago, though as others mention use a liner only as a last resort. A display at a local bike show of destroyed engines and lumps of tank liner was a salutary warning. How well the liner had been applied and what liner is unknown.
 

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So essentially, if you have a properly repaired tank that was rust free, and then had the liner in it it should work well enough? I got a restored SF hump tank what was professionally restored and one of the things I was kind of worried about was the liner in there, which was done as part of the restoration. I'm worried it'll be doing the same as in my old orange SF tank, which looked similar to JotaDave's 1200 tank. (it was done over soldered and rusty spots with predictable results)

So in a good tank that was clean to start with it should hold?
 
jko_78 said:
So essentially, if you have a properly repaired tank that was rust free, and then had the liner in it it should work well enough? I got a restored SF hump tank what was professionally restored and one of the things I was kind of worried about was the liner in there, which was done as part of the restoration. I'm worried it'll be doing the same as in my old orange SF tank, which looked similar to JotaDave's 1200 tank. (it was done over soldered and rusty spots with predictable results)

So in a good tank that was clean to start with it should hold?
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If you have a properly repaired rust free tank, you do not need a liner. Point final.
Paul
 
The tank was already restored for the previous owner, and the restorerer put the liner in. Whether it was his choice or on request of the owner, I don't know. It actually made me doubt to buy it, as not all restorers are created equally and it could just have well been put in to hide a poor job. Looks like it was a proper job though, but it made me wonder if the tank is good, why put the liner in... I don't see the reason.

The tank is still as it came from the restorer, it was never used. Kind of odd to go through the expense and put it on a shelf!
It will be a while before I'll use it myself though, as my bike needs some more cosmetic work, the seat needs fixing (the metal has a big crack in it) and I need some side panels to paint so I can go for GT or SF look (my father dislikes the GT look hence he had the SF tank and seat, despite it being a GT as it looks now, as I ran into a cheap GT tank)

A liner would not have been my choice if it had been my order to a restorer, both my old GT tank and my R90S tank don't have liners and still look very good. (I would not have painted it white and have it look this glossy, too, but that's just a personal preference and for the price of this tank I can't have my old one done by someone else, and don't have the skills myself, so had to compromise a bit there) sf-tank.jpg
 
The ethanol in todays fuel will introduce water. No biggie if new fuel is 'rotating through the system' If bike not used much, a properly prepared surface and good quality liner probably a good idea. Just quietly..BMW's (R90/S as referenced above) actually did have a red film lining the tank.
The bond is good only if the inside is perfectly clean and preferably etched.
 
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