ESE's works engine tuner

[Grumph]

The way to stop seal issues ( and stop moisture in the methanol from rusting all the steel wear surfaces ) was to flush thru the engine on petrol/oil for a few spluttering minutes after every race meeting.

Yep, a small squirt bottle of mix used to fill the float chamber, run it, then drain the carb and lines works fine.

When i was doing a lot of speedway carbs on Meth, I always knew who wasn't cleaning the system after a meeting. The carbs would come back to me a block of white corrosion.....

[nasone32]

I always drained the fuel system and run a minute on petrol after methanol, but i really had no luck with the seals. After 10 minutes they started to leak.
If you want to try the jungle juice:
Now they make viton seals with ptfe lip (for scooter engines, polini makes them) i'd try those ones. Ptfe has no problems.
Pay attention also to the reed cage, if it's covered in viton it can swell. Simple rubber can work. To avoid problems i used a full aluminium one.
Another part that can have problems is the needle valve in the carb, not all can sustain methanol (i found out at my expense).
Oh and also epoxy...

[Frits Overmars]

Check the chart that Frits posted - What is "Still Gas"?

It's registered under 'gaseous'; otherwise I would have thought it was moonshine....

If you want to try the jungle juice:
Now they make viton seals with ptfe lip (for scooter engines, polini makes them) i'd try those ones. Ptfe has no problems.
Pay attention also to the reed cage, if it's covered in viton it can swell. Simple rubber can work. To avoid problems i used a full aluminium one. Another part that can have problems is the needle valve in the carb, not all can sustain methanol (i found out at my expense).
Oh and also epoxy...

And the worst of all possible jungle juice victims: synthetic cages in crankshaft bearings. Some of those cannot even cope with some two-stroke oils...

O, and when playing with methanol: do not try to jet it till the sparkplugs are dry. They're supposed to stay wet with this beverage.

[adegnes]

I always drained the fuel system and run a minute on petrol after methanol, but i really had no luck with the seals. After 10 minutes they started to leak.
If you want to try the jungle juice:
Now they make viton seals with ptfe lip (for scooter engines, polini makes them) i'd try those ones. Ptfe has no problems.
Pay attention also to the reed cage, if it's covered in viton it can swell. Simple rubber can work. To avoid problems i used a full aluminium one.
Another part that can have problems is the needle valve in the carb, not all can sustain methanol (i found out at my expense).
Oh and also epoxy...

It's registered under 'gaseous'; otherwise I would have thought it was moonshine....

And the worst of all possible jungle juice victims: synthetic cages in crankshaft bearings. Some of those cannot even cope with some two-stroke oils...

O, and when playing with methanol: do not try to jet it till the sparkplugs are dry. They're supposed to stay wet with this beverage.

My crankcase has a bunch of epoxy in it, synthetic cages in the bearings and viton seals...oh well, at least there's no reed cage to worry about!

I must admit, in a strange way, it would feel kinda cool to use a fuel that was constantly trying to eat up the engine.
Maybe throw in some nitro to, for good meassure.

[Frits Overmars]

Adegnes, I am delighted to tell you that red-fuming nitric acid is considered a nice oxydant by liquid propellant rocket scientists.
Just don't forget to put on your asbestos underwear before you get on yer bike.

[adegnes]

Adegnes, I am delighted to tell you that rocket scientists have established that red-fuming nitric acid is a nice oxydant.
Just don't forget your asbestos underwear when you get on yer bike.

Hi! This is Alex' girlfriend, please stop planting ideas in his head!

[Frits Overmars]

Yeah, sorry about the asbestos underwear.

[nasone32]

I'd like to link these websites, they give nice informations about various fluids chemical compatibility with rubbers and metals.
the best practice remains direct testing by 24h immersion

http://www.coleparmer.com/Chemical-Resistance
http://www.efunda.com/designstandard...g_chemical.cfm

viton is FKM.

I'm not used to think a low percentage of nitromethane as very dangerous. Also nitro is almost impossible to ignite by accident. Also if you look around, everybody states that it does not mix well with petrol, but i had successfully mixed 10% nitro with pump gas it by adding a 3% acetone in the mix (But don't tell your girlfriend).
Nasty chemical experiments, i know... but I'm sure someone here did even nastier things.

edit: I really don't know about nitric acid production when used in these low percentages...

[lohring]

We did a series of fuel tests on a 26 cc industrial type engine used in model boat racing. The interesting part was how much nitro we could mix with various "gasolines". We found we could get 5% nitro to mix, at least for a short time, with 87 octane, non ethanol gasoline. We had no problem adding 15% nitro to premium gasoline that contained only 8% ethanol because ethanol is a mutual solvent. It was easy to mix methanol with the 87 octane gasoline and we tested 50% and 75% methanol mixtures.

None of the above fuels made any more power because the only thing we changed was the carb mixture setting for best power. More alcohol required a richer mixture. We needed to play with ignition timing and compression ratio to get an improvement, but the engines have a fixed ignition and a one piece cylinder. I also suspect a pipe designed for lower temperatures would have helped.

Lohring Miller

[Frits Overmars]

Nasty chemical experiments, i know... but I'm sure someone here did even nastier things.
edit: I really don't know about nitric acid production when used in these low percentages...

When I was about 14, I mixed my own black powder and sold it to my school mates. At home I made nitroglycerin in small doses. And once I accidentally made chlorine, of which you only need a small dose... It's a miracle I survived my investigative youth.
If you have a bike made of gold, you don't need to worry about nitric acid. Otherwise low percentages of the stuff will quietly nibble your bike away...

[bjorn.clauw.1]

When I was about 14, I mixed my own black powder and sold it to my school mates. At home I made nitroglycerin in small doses. And once I accidentally made chlorine, of which you only need a small dose... It's a miracle I survived my investigative youth.
If you have a bike made of gold, you don't need to worry about nitric acid. Otherwise low percentages of the stuff will quietly nibble your bike away...

mixing it with hydrochloric acid will make the golden bike owners worry a bit.

(cooking nitroglycerin demands some serious self-confidence, ever got any on your skin?)

[trevor amos]

Hi,
I ruined the main bearings on my OS40 4t model aircraft engine after running methanol with 10% nitro, I neglected to flush the engine through with nitro less fuel for a few moments, didn`t take long for the nitric acid to destroy the whole bottom end
Nasty stuff that acid and equally nasty stuff is methanol, be very careful with it you have been warned!

Trevor

[TZ350]

When I was about 14, I mixed my own black powder and sold it to my school mates. At home I made nitroglycerin in small doses. And once I accidentally made chlorine, of which you only need a small dose... It's a miracle I survived my investigative youth.

The 60's and 70's were simpler times.



Now official over reaction can make modern life dangerous for an inquisitive youth.

[adegnes]

I'll stick to my relatively safe toulene/xylene/gasoline mix for now.
On a side note, methanol is very difficult to obtain in Norway cause some people made a habit of drinking it. Also anything with "nitro" in the name has gotten really restricted.

[Lightbulb]

I was told that nitric acid is not formed when Nitromethane is burnt in an engine. But I disagree. Anyone standing behind a nitro burning engine knows the burning sensation of the exhaust gases through your nostrils. I use ATF oil as an after run oil. It will neutralise the acid residues from the nitro fuel. It also helps to run the engine out of fuel when hot. While still warm is when I add the AFT oil. I have not come across pure Nitromethane for more than 25 years. The test the guy I bought it from, was he had a small lid, put some nitro into it. Then he would get a match light it and place it into the nitro, the match would go out. He then let the match soak a little, then would light the end of the match. The Niro burnt as it wicked up the match. If the entire lid full was on fire, he knew it had something else added to it. The last lot he brought failed the test he did. But as it was then his only source we settled to still use it. On model engine testing , we often found that Nitro contents less than 10% , often made the same power as fuel with just methanol and oil, but the small amount of nitro made the engines a lot easier to set the needle position. To mix Nitro to petrol , using Meths works very well.
Neil