My nitro 2.5 engine has a few scratches on the side of the piaton and on tge head of the piston very small scartches. The problem is i gotta give it half throttle to idle i cleaned carburetor and piston it has good compression i dont know whats the problem.
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My nitro engine?
- Thread starter Joseph123
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monstertruckier15
RCTalk Addict
Traxxas 2.5 carbs are 4-1/2 high needle and low is .020 turn in from flush. Idle should be 1mm open. Make sue to use a fuel filter and fuel with 14-18% oil lube.
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@Joseph123 take a look at the Nitro Tuning Tips and Tuning Flow Chart
- Thread starter
- #4
Yea i noticed that the carburetor is ki da broken and it leaks conpression ik gonna have to buy a new one
monstertruckier15
RCTalk Addict
$20 on ebay. Check the setting on new on and set to setting I suggested.
D3MON
Hardcore RCTalk User
it sounds like your LSN is very rich requiring you to ultimately have a wide idle gap, return to factory settings 4 turns HSN and flush on LSN, this will also be rich, very rich, but you will have a basis to start with that should run. also make sure your idle gap is 0.7mm-1mm.
from there use the chart as above posted by Woody.
another thing to check is make sure everything is airtight, they wont run correctly with leaky exhaust gaskets, fuel lines, leaky carb o-rings, carb boots, and fuel filters (pesonally i advise against them and recommend just taking care to prevent debris from getting to the fuel.) your fuel tank should have stone filter already built in.
i have to kindly disagree with the above running more than 14% oil in the fuel, all it does is make the tuning window narrower.
monstertruckier15
RCTalk Addict
You couldn't be more WRONG with the oil lube content. My engines run better with 18% oil lube. 14% is the lowest anyone should go for bashing. Traxxas fuel is 14%. It prevents a lean run and extends engine life. As for the needle setting I use 4-1/2 high and low flush .020 turn in and Idle 1m.to start. 4 turns on the high is just about the max turn in You can't go past or ruin you engine. I have 10 tmaxx's and set them all the same.
D3MON
Hardcore RCTalk User
how exactly is more Lubricant going to increase the FUEL in an air fuel ratio? lean running with high oil content is still running lean, still driving up run temperatures.
also wouldnt mind seeing where you confirmed Traxxas top fuel has 14% oil.
so factory/break in settings are what you run your engines at without leaning them out? i... got really no words except that confirms the point to never run air fuel, and i cannot recommend your tuning advice, if it works for you great.
really dont think there is any reason to talk to you further regarding oil content, I'm content enough to agree to disagree with you.
monstertruckier15
RCTalk Addict
Oil lube has nothing to do with air fuel mix ratio. All that's in nitro fuel is nitro methanol and synthetic blend oil special. The only thing that burns is methanol and nitro? Oil lube is a liberate to reduce friction and promotes a good seal making your engine last longer. Less oil lube has more chances of lean run and higher temps. My engines run @200 degrees fine with 18% oil lube.
Regular Blend - S-W Fuels (s-whobby.com) What I currently use!
Traxxas fuel is 14% fact. Everyone know it's junk! But it runs. As for factory setting I always suggest the high be 4-1/2 as you will have more break in adjustment to understand tuning better. None of my traxxas engine's are past 4 turns on high. Stay away from 4 turns the longer the better. But???? This is why so many people ruin a engine so fast. A nitro Engine is expensive. I guess you can jut drop a new one in every year. I have engines over 30 years old and they still have excellent compression. I'm only talking about % by volume which isn't very much. You seem to think is a lot. As for fuel it's all the same. You just pay more for car fuel and by the Quart which is the biggest rip off!. I even run 4 stroke fuel too. It's all the same .A true sucker born every minute who buys car fuel. Why don't you run 8% oil lube. Less oil lube is for racing when you need to get more laps out of a tank of fuel and you throw away the engine in a season. Pure junk for backyard bashing.
Buying different types of fuel is just pure stupid and expensive. I run heli.,air, boat and buggy/truck. So there is nothing wrong with buying one type of fuel for all. Its cheaper to buy in volume than buying quarts.
As a old school guy the engines I run are from 1985-2000 and I don't need no car fuel. Os only recommends 18% oil lube so that's all I will use and recommend. It's 100% safe for all nitro engines.
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D3MON
Hardcore RCTalk User
oil in the case of these model engines, is not fuel. (obviously) so how does it decrease the chance of it running lean? temperature is a byproduct of tune, temperature isnt the tune. that is why these engines operating temperatures vary from 220F-270F, as most manuals will point out, 200F isnt even up to operating temperature, and will put extra un-needed stress on the con-rod and piston.
i HAVE contacted traxxas to get a oil percentage, they "will not disclose trade secrets" please post where they confirmed 14% would like to see it.
air fuel and land fuel is most certainly not the same.
Air fuel uses castor oil primarily because at primarily WOT it is more effective at higher temperatures.
land fuel uses a mix of synthetic oil which is more effective and efficient lubricator, with a trade off that it will be less effective at higher temperatures, so they add castor oil to compensate for the effective range of synthetic.
I'm not going to get into the price end of it, because obviously it wont matter because you are too set in your ways. but the above should give an idea of one aspect and common business practice of quantity purchasing takes care of the rest.
either way happy bashing, and enjoy burning some nitro, going to get back to what i said above, done talking with you about it because it wont go anywhere and i dont feel like wasting anymore time.
i HAVE contacted traxxas to get a oil percentage, they "will not disclose trade secrets" please post where they confirmed 14% would like to see it.
air fuel and land fuel is most certainly not the same.
Air fuel uses castor oil primarily because at primarily WOT it is more effective at higher temperatures.
land fuel uses a mix of synthetic oil which is more effective and efficient lubricator, with a trade off that it will be less effective at higher temperatures, so they add castor oil to compensate for the effective range of synthetic.
I'm not going to get into the price end of it, because obviously it wont matter because you are too set in your ways. but the above should give an idea of one aspect and common business practice of quantity purchasing takes care of the rest.
either way happy bashing, and enjoy burning some nitro, going to get back to what i said above, done talking with you about it because it wont go anywhere and i dont feel like wasting anymore time.
monstertruckier15
RCTalk Addict
You just answered you own question. More oil protects the engine and can prevent a lean run. So keep on running less oil. IT'S PURE JUNK!~ Not good for back yard bashing. If I ran 14% oil then it would be 220 degrees BUT I run 18% oil so 200 degree it is. I will never run any nitro @ 270 degrees. Fuel is fuel All the ingredients are the same. You just don't get it???? Car fuel is race fuel It's pure junk for OS engines. Not good for back yard bashing. So keep on wasting you time. Car fuel is a get rich fuel. Buy it and buy a new engine sooner. It's all about the % of oil lube between land and air. Before you were born and car fuel all there was was air fuel. Your just a sucker that believes' car fuel is better than air fuel by the hobby shops to make money with quarts.
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D3MON
Hardcore RCTalk User
lean mixture is lean mixture, no amount of oil is ever going to change that. oil is not fuel... oil has nothing to do with AFR which is the determining factor on if it is lean, rich, or well tuned.
the only question i asked was to get proof of traxxas Top Fuel oil content, which i am still patiently waiting on.
IMO you are the sucker in this case sacrificing engine protection for just a few bucks because you don't want to spend the money on getting proper fuel with the correct types of oil, but i am trying to be respectful and not bashing other members just because they have different opinions that i have.
there was also no context regarding O.S. engines, nor was this post about an O.S. engine.
i am sick of the lack of your lack of respect and your attempting at demeaning comments.
your responses dont warrant any kind of response, ramble on if you want, i dont care to respond to you further.
the only question i asked was to get proof of traxxas Top Fuel oil content, which i am still patiently waiting on.
IMO you are the sucker in this case sacrificing engine protection for just a few bucks because you don't want to spend the money on getting proper fuel with the correct types of oil, but i am trying to be respectful and not bashing other members just because they have different opinions that i have.
there was also no context regarding O.S. engines, nor was this post about an O.S. engine.
i am sick of the lack of your lack of respect and your attempting at demeaning comments.
your responses dont warrant any kind of response, ramble on if you want, i dont care to respond to you further.
