Ethanol and your brass floats

[John D.]

Typically I will test a float for two days in gas to see if it is a leaker. I do this outside of course. Sometimes I test them in a glass coffee pot, etc.
Now for the problem at hand. I tested a spotless brass float in ethanol for 4 days. This ethanol was just bought by my son for the power mower at our local serice station. I suspect it's 87 octane.
I was shocked to see that the float had turned filthy black. Black and other colors none of which resemble brass. Appears that the wonderful ethanol is also attacking the brass floats big time.
Very upsetting so it is. Now this problem isn't just the fuel injections. It has to be happening to the carburetors also. Will the blackening hurt the float? The answer is YES.
Sometimes it takes a while for me to catch on to the problem. I have been wondering why so many of the floats appear to have been put in some kind of acid. Now I know the answer to the etching of the float is ethanol.

[Rob M.]

Re: Ethanol and your brass floats

Typically I will test a float for two days in gas to see if it is a leaker. I do this outside of course. Sometimes I test them in a glass coffee pot, etc.
Now for the problem at hand. I tested a spotless brass float in ethanol for 4 days. This ethanol was just bought by my son for the power mower at our local serice station. I suspect it's 87 octane.
I was shocked to see that the float had turned filthy black. Black and other colors none of which resemble brass. Appears that the wonderful ethanol is also attacking the brass floats big time.
Very upsetting so it is. Now this problem isn't just the fuel injections. It has to be happening to the carburetors also. Will the blackening hurt the float? The answer is YES.
Sometimes it takes a while for me to catch on to the problem. I have been wondering why so many of the floats appear to have been put in some kind of acid. Now I know the answer to the etching of the float is ethanol.

Mmm, that is VERY scary...

[Stuart F.]

Re: Ethanol and your brass floats

Can't say I'm seeing that with my AFB floats. My 3721SB, which I ran for a number of years on ethanol laced gas, only shows a slight discoloration toward brown or tan. I had it apart a number of times for jetting changes, and actually cleaned the floats once, and I test them every so often. They seem to be holding up well (ditto my 3720SA which I also ran for a while). I have now run non-ethanol for close to a year and the floats looked the same on my last disassembly. I always used Max lead 2000 TEL, but doubt that had anything to do with it.

Stu Fox

[Larry M.]

Re: Ethanol and your brass floats

Typically I will test a float for two days in gas to see if it is a leaker. I do this outside of course. Sometimes I test them in a glass coffee pot, etc.
Now for the problem at hand. I tested a spotless brass float in ethanol for 4 days. This ethanol was just bought by my son for the power mower at our local serice station. I suspect it's 87 octane.
I was shocked to see that the float had turned filthy black. Black and other colors none of which resemble brass. Appears that the wonderful ethanol is also attacking the brass floats big time.
Very upsetting so it is. Now this problem isn't just the fuel injections. It has to be happening to the carburetors also. Will the blackening hurt the float? The answer is YES.
Sometimes it takes a while for me to catch on to the problem. I have been wondering why so many of the floats appear to have been put in some kind of acid. Now I know the answer to the etching of the float is ethanol.

John:

I would suspect other impurities such as sulfur before believing that ethanol causes this. I am not an advocate for ethanol-laced fuel, but not certain that ethanol is the guilty party in this case.

We are seeing crude feedstocks coming from more and additional sources. Also, any upset in the refinery operations can cause problems. We had a situation a few years back with Shell gas here in SE Louisiana. A problem at the refinery caused a high sulfur break thru in the refining step, which caused MANY gas tank sending units on area cars to simply fail. I think the 87 octane level gas is also the worst, since it is the default blend and gets the rejects from the other grades.

Larry

[Don H.]

Re: Ethanol and your brass floats

I recently backed my mid-year running a 7017375 unit out of the garage. Fortunately an automatic door opener is very low on my to do list for the new garage. When I got out to close the door I smelled fuel, opened the hood and there was gas everywhere. The float had failed and it could have been a disaster had I drove away and heated up the engine. To John's point, I only run Aviation fuel except when traveling and must run pump gas. Thanks for the heads up. Don H.

[Michael J.]

Re: Ethanol and your brass floats

This is one reason I quite using ethanol laced gas, I drive a bit out of my way to get the ethanol free. I had a lean stumble issue with my Holley that had been totally restored just three years before. In taking it apart, the discoloration and corrosion was evident. Since then only non-ethanol 90 octane and have never had any more problems. But I know there are many ethanol fans around, so tread carefully about being critical of it.

[Tom H.]

Re: Ethanol and your brass floats

I would look for another cause. Generations of bootleggers have used brass stills to make their product - ethanol. Ethanol is a solvent, used in many carburetor cleaners.

That's not to say ethanol can't cause problems with old-style gaskets and seals that weren't designed to be resistant.

[Michael J.]

Re: Ethanol and your brass floats

I have never seen ethanol used for a carb cleaner solvent. They are petroleum based solvents, like acetone, xylene, toluene, methyl ethyl ketone, ethyl benzene, and glycol alkyl ethers. That is how the varnish gets taken off, ethanol is far too weak, and hydrophilic, a solvent for all that.

[Paul J.]

Re: Ethanol and your brass floats

I would look for another cause. Generations of bootleggers have used brass stills to make their product - ethanol. Ethanol is a solvent, used in many carburetor cleaners.

That's not to say ethanol can't cause problems with old-style gaskets and seals that weren't designed to be resistant.

Copper, Tom, it's copper. Copper for the cap, lines, and the worm. Steel, copper, wood or a combination of these materials for the pot. Now I'm thirsty!

I just googled "ethanol and brass carburator float" and got more hits than I can post. I can't read all of them, but one suggestion was to paint the floats. I have'nt found any discussion on the reasons, but I wonder if the moisture in ethanol, combined with something else (like sulfer), might be contributing to the problem.

[Michael J.]

Re: Ethanol and your brass floats

Hate to make yet another ethanol thread, but this is a government bulletin issued a few years ago about ethanol and "soft" metals interactions in our underground storage tanks:

http://www.in.gov/idem/files/la-072-gg.pdf

Where it states:"....

[Dick W.]

Re: Ethanol and your brass floats

Copper, Tom, it's copper. Copper for the cap, lines, and the worm. Steel, copper, wood or a combination of these materials for the pot. Now I'm thirsty!

Copper somewhat counteracts the fusel oils, the foul taste, in homemade likker

[John S.]

Re: Ethanol and your brass floats

I changed my fuel to R90 " Recreational 90 octane " no ethanol and my 63 runs the best it ever has in the 11 yrs I've owned it.

[Larry M.]

Re: Ethanol and your brass floats

I have never seen ethanol used for a carb cleaner solvent. They are petroleum based solvents, like acetone, xylene, toluene, methyl ethyl ketone, ethyl benzene, and glycol alkyl ethers. That is how the varnish gets taken off, ethanol is far too weak, and hydrophilic, a solvent for all that.

The "fast acting" carb cleaner solvent used many years ago was methylene chloride. It is still available today, but you have to search. It likes to attack bare skin in addition to removing varnish and gum from the carb.

I have never seen ethanol used for a carb cleaner, but I think I remember some that contained methanol along with other ingredients . Distilled and refined ethanol is used for other worthwhile purposes, not as a carb cleaner

Larry

[Terry M.]

Re: Ethanol and your brass floats

I thought 1 1 1 trichlorethlane was used in carb cleaner back when. That sucks up water like a sponge.

[Michael J.]

Re: Ethanol and your brass floats

Back in the day, 1 1 1 trichloroethane (or methyl chloroform as we used to call it, it was banned by the Montreal protocol) was used on electronics. I don't remember ever using it as a carb cleaner, but it worked well on my old circuit boards and tube TVs....