Marko36608
RC Newbie
Just bought a SH .28 8 port engine.
What is the best % of Nitro Fuel and Oil % to Break in Engine and to continue using?
What is the best % of Nitro Fuel and Oil % to Break in Engine and to continue using?
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Losi215
RCTalk Racer
Something with 10-12% oil for break in, preferably 12%. Once broke in, I would run bones brew 30% nitro with 10% oil blend if you live in the states. If In Europe, run what your local hobby shop has available.
Marko36608
RC Newbie
- Thread starter
- #3
Thank you very Much for your help...
cbaker65
RCTalk VIP
Bones brew also has a break in fuel an can be added in a 3 gallon order of 12 quarts
with one quart of the regular fuel removed!
Bones brew is your best choice for shipping & price as well ,they use VP fuels
in their mixture ,so it is top quality fuel!..
https://www.bonesmotorsports.com/Bo...s-Free-Shipping-USA-Lower-48-states_p_25.html
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Bones is great stuff. For bashing, the 30/10 is awesome. The 30/8 is good for drag racing.
burnskevin58
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I don't follow lengthy break in procedures. The only time is if it's an ABN engine, then I run two tanks slightly richer back-to-back, but I do religiously use FHS Oils Red Max 40% fuel.
33% vs 40% fuel makes a huge difference in power.
One of the most known names in model engines is K&B, I don't make this sht up.
Here is what K&B says to do. This says 2 runs "No less" than 5 minutes, remember back in the day our fuel tanks were smaller, today we can run 10 minutes from one tank, so K&B is saying run it between 25-50% nitro and run it straight for 10 minutes at a slightly richer setting to break it in, then adjust for a leaner setting.
This is from their racing 3.5cc engine, same as any high-power engine today, these racing engines were 33,000+ rpm engines. The marine and car/buggy engines are identical except for the heads (Cooling vs heat Sink) and have the same break in procedure and fuel recommendations as K&B only sold two percent's of fuel 25% and 50%.
Basically he's saying "Run the engine and shut up" LOL
I just can't find an on-line manual for the car race engines; the screen shot is from the Mecoa website.
Notice it doesn't say "Our engines don't require; it say an ABC engine doesn't require.
IMO long break in periods damage the engine and here is why.
In order for the engine to break in, the piston and sleeve must expand, the piston and sleeve expand at different speeds of time due to the different materials, the piston needs to very hot to expand vs the sleeve (The sleeve expands first) so running around for a gallon or two, of low nitro content at a rich setting the engine never reaches the heat required and the piston never expands so the chrome on the sleeve overly wears out and or gets scored from being rubbed on by an unexpanded piston slapping and micro rocking, overly thinning the chrome. So, an engine that never was broken in will only wear out in a season. But that's just me.
The above is also why it's recommended to run the same fuel for break in as you will for high-speed running, if you break in on 20% and go to 33% after breaking in, the extra heat from the higher nitro content will expand the sleeve more and you won't have good compression. break it on with the fuel you're going to run (This is just me so don't listen).
Then after a 6 months, people say "My engine has no compression", and they can spin the engine over with a glow plug in it. This is because that lengthy break in procedure on low nitro over oiled fuel never let the engine heat up to optimal temp to allow the piston to expand and break in correctly and damaged the chrome (The sleeve expanded but the piston didn't so the chrome is overly worn off because the piston rubbed all the chrome off from not sliding up and down evenly. Then when you think your long procedure broke the engine in and you start going lean, the piston finally starts to expand from finally having the heat required to expand it, and was worn out from the incorrect break in, so now there is no compression due to the piston being out of round and the sleeve being worn down unevenly. I guess it's a good way to sell engines, have people destroy the engine so they buy another in a year and every year thereafter. pretty good marketing strategy.
Rossi told me the same thing about 15 years ago when I was at a race in Illinois.
That being said, nickel is softer than chrome and thicker plated so for ABN engines, I run slightly richer for two tanks or 20/25 minutes then go leaner.
That's just me but my engines last forever. I know nickel is softer than chrome what that means is by being nickel-plating vs chrome engines, so you have to run them a little longer richer to allow for this thicker plating.
33% vs 40% fuel makes a huge difference in power.
One of the most known names in model engines is K&B, I don't make this sht up.
Here is what K&B says to do. This says 2 runs "No less" than 5 minutes, remember back in the day our fuel tanks were smaller, today we can run 10 minutes from one tank, so K&B is saying run it between 25-50% nitro and run it straight for 10 minutes at a slightly richer setting to break it in, then adjust for a leaner setting.
This is from their racing 3.5cc engine, same as any high-power engine today, these racing engines were 33,000+ rpm engines. The marine and car/buggy engines are identical except for the heads (Cooling vs heat Sink) and have the same break in procedure and fuel recommendations as K&B only sold two percent's of fuel 25% and 50%.
Basically he's saying "Run the engine and shut up" LOL
I just can't find an on-line manual for the car race engines; the screen shot is from the Mecoa website.
Notice it doesn't say "Our engines don't require; it say an ABC engine doesn't require.
IMO long break in periods damage the engine and here is why.
In order for the engine to break in, the piston and sleeve must expand, the piston and sleeve expand at different speeds of time due to the different materials, the piston needs to very hot to expand vs the sleeve (The sleeve expands first) so running around for a gallon or two, of low nitro content at a rich setting the engine never reaches the heat required and the piston never expands so the chrome on the sleeve overly wears out and or gets scored from being rubbed on by an unexpanded piston slapping and micro rocking, overly thinning the chrome. So, an engine that never was broken in will only wear out in a season. But that's just me.
The above is also why it's recommended to run the same fuel for break in as you will for high-speed running, if you break in on 20% and go to 33% after breaking in, the extra heat from the higher nitro content will expand the sleeve more and you won't have good compression. break it on with the fuel you're going to run (This is just me so don't listen).
Then after a 6 months, people say "My engine has no compression", and they can spin the engine over with a glow plug in it. This is because that lengthy break in procedure on low nitro over oiled fuel never let the engine heat up to optimal temp to allow the piston to expand and break in correctly and damaged the chrome (The sleeve expanded but the piston didn't so the chrome is overly worn off because the piston rubbed all the chrome off from not sliding up and down evenly. Then when you think your long procedure broke the engine in and you start going lean, the piston finally starts to expand from finally having the heat required to expand it, and was worn out from the incorrect break in, so now there is no compression due to the piston being out of round and the sleeve being worn down unevenly. I guess it's a good way to sell engines, have people destroy the engine so they buy another in a year and every year thereafter. pretty good marketing strategy.
Rossi told me the same thing about 15 years ago when I was at a race in Illinois.
That being said, nickel is softer than chrome and thicker plated so for ABN engines, I run slightly richer for two tanks or 20/25 minutes then go leaner.
That's just me but my engines last forever. I know nickel is softer than chrome what that means is by being nickel-plating vs chrome engines, so you have to run them a little longer richer to allow for this thicker plating.
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