Ethanol induced rust on fuel level sender

Removed the fuel sender from an otherwise good-looking tank that came with my project XJ900F ...


It was not surprisingly seized on the pivot. Got it free and am busy removing rust.

 

Ethanol does not cause rust. Water does.

 

That rust is not from the fuel.

 

Correct; however water and ethanol bond. We call it phase separation in the petroleum industry. The water may have been already bonded and the fuel supplier was not using phase separation filters.

 

Agreed. I am just so used to people in the (currently) science-literacy-challenged U.S. blaming ethanol for things that ethanol doesn't do (unless people abuse their vehicles).

Also, we see rust in tanks and on sending units even in areas where ethanol blends are not sold.

 

That sir, is an ongoing epidemic and I couldn't agree with you more.

 

I just saw the second part of your quote. I have seen how water enters storage tanks, with a bike if the fuel tank isn't filled prior to winter storage can it condensate with temperature fluctuations?

 

Indeed it can, and does. That's why private airplane fuel tanks have water drains you're supposed to check as part of the preflight. Even a short time sitting with a partial tank can cause an ounce or more of water to condense (depending on local temperatures and humidity).

 

Yes I am going to check my tank and probably seal it. I have heard good reports about POR15.

 

I'm not really into hairsplitting or semantics.
Perhaps I should add a question mark at the end of the title ?
I'm very well aware of other causes of rust/corrosion. I totally agree that condensation can play a major role.
I'm not quite sure if ethanol is not a factor - rather hard to be pedantic/accurate after a few years when presented with a sender like this, a fuel cap so corroded the 'sliders' were jammed out, fuel tap bolts and sender bolts that were hard to remove because the exposed sections of thread within the tank had gone rusty ...
Fact is - I started a Porsche 924S that had been sitting unused for years - since well before ethanol was forced on us in the UK.
Petrol in the half-full tank was obviously very stale but the engine started easily with just a fresh battery and ran on all cylinders. No injectors were jammed.
I admit to being surprised.

In contrast I have found mowers and motorcycles left for just one winter with ethanol-blended petrol refusing to start until a complete fuel change has taken place. The vintage car people claim it is/will be affecting soldered joints in older fuel systems.
Certainly I found green corrosion on the SU needles of an HRG left for about a year AND translucent 'jelly' in the mechanical fuel pump.
I have never before had such problems in over fifty years working on similar systems.
I'm still tempted to categorize it as an ill-thought-out and inadequately-tested 'green' idea to "save the planet".

Like Franz, I've heard good reports on POR15 and will almost certainly line this tank with it.
Years ago I did a 15 gallon steel tank on an Allard with 'aircraft industry' sealant (blue colour is all I can recall) and ten years later it was still functioning well.

 

A few pennies worth of fuel stabalizer eliminates all those ethanol related problems. 30 years of using the stuff (E-10 gas), no troubles yet.

 

K-moe what kind of fuel stabilizer do you use? Will it prevent the rusting through of the lowest part of my XJ 900F tank?

 

I use Sta-Bil for ethanol, but there are others that do the same thing. It may be more of a challenge since you live in a more humid environment (though I had no problems with rust when I lived in Oregon). I also add a dose of Marvel Mystery Oil to the last tank of fuel before I store the bike for winter. I then go for one last ride, and drain the float bowls after.

 

Might try Sta-Bil k-moe and I will keep an eye on the tank because if it starts corroding I am going to POR15 it.

 

That or Caswell's.

 

I wrote a reply last night thanking k-moe but clearly I pressed a wrong button!
I've only got a tiny bottle of Briggs & Stratton fuel stabiliser and am not sure what I'll find in the UK.

Also asked - what is in "Marvel Mystery Oil" or is it still a genuine mystery?

 

Mineral oil, Stoddard solvent, naptha, and some lard for the smell (maybe oil of Wintergreen too)

 

It smells like minty bacon?

 

Yep