HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Nov 04, 2012, 12:21 PM
Dieselized User
gkamysz's Avatar
Chicagoland
Joined Feb 2000
7,393 Posts
Google is pretty good, huh? Right, so which are unsuitable?

Greg
gkamysz is offline Find More Posts by gkamysz
Reply With Quote
Sign up now
to remove ads between posts
Old Nov 04, 2012, 07:14 PM
Registered User
Australia, SA, Adelaide
Joined Sep 2007
629 Posts
My containers are marked number 2 but I wonder on the cap seal and the cap itself . Cheers the pope
the pope is offline Find More Posts by the pope
Reply With Quote
Old Nov 05, 2012, 12:20 AM
Registered User
turk1's Avatar
Istanbul, Turkey
Joined Aug 2004
847 Posts
Once I saw,supposedly PET water container got melt in seconds when buddy try to put his share of common brew fuel.But I saw also real PET s are not affected from nitro.Who knows what was in that plastic.My electronic balance (ABS) became very ugly when I accidentally let go of several nitro droplets on its base plastic.So I recommend you to have pretest before one needs to transfer any nitrous fuel into any plastic container.
turk1 is offline Find More Posts by turk1
Reply With Quote
Old Nov 05, 2012, 08:42 AM
Registered User
Nav_Aids's Avatar
Canada, MB, Winnipeg
Joined Nov 2011
332 Posts
Quote:
Originally Posted by gkamysz View Post
Google is pretty good, huh? Right, so which are unsuitable?

Greg
I'm not sure Greg which one's are unsuitable, other than what's stated in the PDF. I've worked with pure nitro but, we used nitro approved fuel jugs and used metal pumps to transfer it from metal drums to the fuel jugs. The hand pumps were usually good for one season, then needed to be rebuilt (seals and hose). Which plastics got softened was a bit of hit and miss, they don't label the plastics, and tthere are lots of different ones out there. As for RC, I keep the fuel in the jug it came in on the shelf in the basement until I need it.

Ray
Nav_Aids is offline Find More Posts by Nav_Aids
Reply With Quote
Old Nov 05, 2012, 09:27 AM
Dieselized User
gkamysz's Avatar
Chicagoland
Joined Feb 2000
7,393 Posts
The suggestion was that nitro is incompatible with certain types of materials but did not specify which. How are you going to test a bottle for months before deciding if it's suitable? Pure nitromethane will certainly be shipped in compatible containers. While documentation says that pure nitromethane is incompatible with HDPE, I've seen glow fuel up to 40% nitromethane in HDPE bottles. We know pure nitromethane is a great solvent. Many containers are layered, a soda or ketchup bottle can have 6 layers of plastic today. I've used PET water bottles for FAI fuel and kerosene. The bottle was fine but with methanol, the caps failed on some water bottles very quickly, while others have been OK for years. The plastic film labels on water bottles peel off quite nicely and you make your own. Many use plastic water bottles for fuel tanks in giant scale models with gasoline, usually with a kit where the cap only holds a plug with the fittings.

http://www.nalgenunc.com/pdf/Nalgene...hGuide0209.pdf

Page 54, nitromethane 100%, is incompatible with most common plastics.

Greg
gkamysz is offline Find More Posts by gkamysz
Reply With Quote
Old Nov 05, 2012, 10:48 AM
Registered User
earlwb's Avatar
USA, TX, Grapevine
Joined Dec 2008
13,351 Posts
I thought of a interesting conumdrum with the RC gas engines to talk about.

How come we have to rebuild the carbs on the RC gas engines so often? I mean I usually have to replace the regulator diaphragm more often that I would think I have to. Just this Sunday, I went to fly a plane and the carb was flooding out the engine. Sure enough putting in a new diaphragm fixed the problem as the old one stretched out too much. I had another engine last weekend quit on me when I went to run it for its fourth flight of the day with the same problem. But it worked fine for those first flights though.

But I can go an buy a new trimmer engine or chainsaw, etc, from the local big box hardware store and it works for years with no care at all, just fuel it up and go. Granted it only gets used about every other weekend for a hour or two. But I never rebuild the carb on it, replace the spark plug, or even need to adjust the needle valves for that matter. I usually have to scrap it out after a number of years because you can't get parts for it when the tool head breaks or something, but the engine is still OK albeit dirty and cruddy looking.

So how come we have to mess around with the RC gas engines so much?
earlwb is online now Find More Posts by earlwb
RCG Plus Member
Latest blog entry: My new Gaui X5 Rc Helicopter
Reply With Quote
Old Nov 05, 2012, 11:13 AM
Registered User
Joined Mar 2007
1,079 Posts
I ran petrol engines exclusively, for quite a few years. Never had to rebuild a carb.

So, that's a puzzle.
bogbeagle is offline Find More Posts by bogbeagle
Reply With Quote
Old Nov 05, 2012, 12:16 PM
Complete RC Idiot Savant
The Netherlands
Joined Nov 2009
2,969 Posts
Same here.... running 3 Zenoahs, the oldest one for 7 years now and the youngest over 4 years, but never a problem with the carb.
Had a problem with the spark plug cap on both of the flying ones but that was a 5 Euro fix for the two of them, and it was the only issue I ever had with these engines....

Brgds, Bert
Brutus1967 is offline Find More Posts by Brutus1967
Reply With Quote
Old Nov 05, 2012, 02:29 PM
Registered User
earlwb's Avatar
USA, TX, Grapevine
Joined Dec 2008
13,351 Posts
I think it is a matter of the type of gasoline we use here in the USA versus what others are using outside of the USA. They are adding a lot of chemicals to the fuel along with ethanol as well. At present it is something like 40 different hydrocarbon substances being added to the fuel.
earlwb is online now Find More Posts by earlwb
RCG Plus Member
Latest blog entry: My new Gaui X5 Rc Helicopter
Reply With Quote
Old Nov 06, 2012, 10:24 PM
The Prez....... again
kenh3497's Avatar
United States, IA, Rockwell
Joined Jul 2011
4,162 Posts
If you by fuel from a "blender" pump. (a pump that dispenses various fuels from one hose) Beware that the hose and pump can contain up to two quarts of the previous fuel. So, if the person before you bought E-85 and you filled your one gallon container you may have 35/40% ethanol in your container. 99% or more of all small engine carbs will only tolerate 10% or less ethanol.

The moral of the story is... Fill you car first, or at least a gallon or two in the tank before you put any in your model fuel jug.

Ken
kenh3497 is offline Find More Posts by kenh3497
Reply With Quote
Old Nov 06, 2012, 11:22 PM
Complete RC Idiot Savant
The Netherlands
Joined Nov 2009
2,969 Posts
Quote:
Originally Posted by kenh3497 View Post
If you by fuel from a "blender" pump. (a pump that dispenses various fuels from one hose)
You have filling stations using one hose for different fuels?????

Never seen that over here....

Seems to me, not the most clever invention.... like a bar selling beer and soda from the same tap....

Brgds, Bert
Brutus1967 is offline Find More Posts by Brutus1967
Reply With Quote
Old Nov 07, 2012, 02:17 AM
Registered User
Joined Mar 2007
1,079 Posts
Quote:
Originally Posted by Brutus1967 View Post
You have filling stations using one hose for different fuels?????

Never seen that over here....

Seems to me, not the most clever invention.... like a bar selling beer and soda from the same tap....

Brgds, Bert




Do you remember the episode of "The Simpsons" where Homer visited the Duff Beer Factory?

He sampled the various (different) brews, taking a drink from each of the beer taps ... but all the pipes led back to one gi-normous "common pipe.".
bogbeagle is offline Find More Posts by bogbeagle
Reply With Quote
Old Nov 07, 2012, 09:54 AM
The Prez....... again
kenh3497's Avatar
United States, IA, Rockwell
Joined Jul 2011
4,162 Posts
Quote:
Originally Posted by Brutus1967 View Post
You have filling stations using one hose for different fuels?????

Never seen that over here....

Seems to me, not the most clever invention.... like a bar selling beer and soda from the same tap....

Brgds, Bert
Gasoline here has varying amounts of ethanol in it. Up to 85% ethanol in some parts of the country. Of course your vehicle has to be capable of using that high content of ethanol. That is where the blender pumps come in. Less expense for the retailer to have one pump. The most common is a 10% blend, which will work fine in our models. Now 15% is coming into play along with the mentioned 85%. Two quarts of 85% in a 20 gallon tank is of no consequence in a car. Two quarts of 85% in your one gallon model fuel container just won't work.

Ken
kenh3497 is offline Find More Posts by kenh3497
Reply With Quote
Old Nov 07, 2012, 10:24 AM
Dieselized User
gkamysz's Avatar
Chicagoland
Joined Feb 2000
7,393 Posts
Around here, E85 is dispensed from a different pump and tank. Stations here have two tanks for gasoline, one for 87 octane and one for 92/93 premium, mid grade is blended.

The problems with model carb diaphragms is not due to our type of fuel. Countless people rely on diaphragm carbs daily for their jobs and life. I think it's the amount of time spent idle that destroys the diaphragms. As certain portions of the fuel evaporates, this leaves a different makeup and could effect the diaphragm material. In addition hand cranking is much slower than a pull start, so getting the pump diaphragm to move fuel is not as easy when hand propping.

Has anyone taken apart a good carb to see what the metering diaphragm looks like in a tool several years old? I'm guessing they too are distorted and stretched, just not to the point where they don't work. The bad ones I've seen were stiff.

There are people who race with diaphragm carbs on methanol and they say they hold up fine for at least a season. I've read about some people running E85 in gassers and they had no complaints about carbs.

Fuel is made up of a mess of hydrocarbons. Gasoline is not a pure substance with 40 hydrocarbons added to it. All you ever wanted to know about gasoline, Chevron Gasoline Technical Review.

Water in ethanol fuel is a problem. Mistakes happen at refineries. There was a problem with BP fuel in the Midwest and there were claims on 8000 cars last time I heard.

Greg
gkamysz is offline Find More Posts by gkamysz
Reply With Quote
Old Nov 07, 2012, 10:47 AM
Registered User
earlwb's Avatar
USA, TX, Grapevine
Joined Dec 2008
13,351 Posts
The other thought I had was that the I suspect that the carb rebuild kits are all being made in China, and there may be lots of counterfeit or fake rebuild kits too. So we may not being getting as good parts that we think we are getting. Even ordering that "official" packaged Walbro carb rebuild kit, may not really be from Walbro. I seem to go several months before a diaphragm on some engine goes bad on me.

It just seems odd that my chainsaw which gets seldom used, or my trimmer or leaf blower which only get used every other weekend have not had their carbs that go bad where the diaphragms have stiffened up or stretched out on me. They are all several years old now.
earlwb is online now Find More Posts by earlwb
RCG Plus Member
Latest blog entry: My new Gaui X5 Rc Helicopter
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion OFFICIAL KDS 450s /sv THREAD / HELP - DISCUSSION - GENERAL - #for all kds needs d1cky_kds Electric Heli Talk 20 Mar 27, 2014 09:28 AM
Build Log J-Power A-10 build, mods, general discussion thread gunracer Foamy EDFs 199 Jul 29, 2012 01:49 PM
Discussion Aero Titan Discussion Thread PinkYakRC 3D Foamies 4 Apr 13, 2012 11:14 PM
Discussion OPEN discussion thread DLGjunkyard Hand Launch 62 Mar 19, 2012 12:09 AM
Discussion "Attention LSF members" - discussion thread Miami Mike Thermal 16 Mar 14, 2012 09:24 PM