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need help on my mill

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K

koolkat01

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hello everyone i had a question i had a problem breaking in my savage x 4.1 it didn't idle on the fist tank it was at a high rpm i tried to lower the idle then it cut out so i left it at a high rpm then i ran it at low speeds like the book stated i mean i did everything the book said so now when i try to start it up i have to let it get hot first then adjust the needle so it can stay running after the fist tank i let it cool then start up again but then it won't stay running i reset all needle to factory and then it runs but when i try to throttle it shuts down and then you here a clink i adjust and adjust but wont stay running so i give up and try the next day and the same thing happens.
back to break in the temps went up to the 300's just wanted to know whats what if that could be the reason why i'm having so much of a problem
 
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Are you copying this post from a different forum?
 
well i can guarantee, you need a new motor!!!
300's during breakin yells out to me "MOTOR IS FU**ED"
and also i have not heard anything good about 4.1's everything bad
you may want to consider getting a different brand of motor or the only faultless motor from HPI the STAR .25

hope i could help

really, sound like it needs to be tuned rich, but i know right now that the motor has damage from being 300 degrees DURING BREAK IN!!!!!

YIKES
 
I believe the 4.1 is the S25 just rebadged. The S25 is a tough as nails motor that likes to run hot.
 
redneckracer1979 said:
I believe the 4.1 is the S25 just rebadged. The S25 is a tough as nails motor that likes to run hot.
Click to expand...

Completely different engine. The only thing the F4.1 shares with the S25 is the backplate, pullstart, and cooling head (and a few other assorted parts).

If your engine is hitting 300F+ at idle, you have a serious air leak. Make sure your carb is locked down firmly, and your needle o-rings are not torn. If those check out, set the high and low to flush (factory settings), and make sure your glow plug is tight.

Keep with it, the F4.1 is a good engine for a first engine once broken in.
 
I had a hell of a time breaking my 4.1 in as well. Although I did it at -20 degrees Celsius but finally got it after pissing around long enough. I would agree stay with the 4.1 nitro-star, mine has been bullet proof and I beat the hell out of it. 300 degrees?? ya thats hot...i guess if you monitor that. If my savage burbles away at full throttle I lean it out, if it dies out at full throttle I richen it up...temperature schwemperature...haha

you may have a problem with the engine if the thing still won't run...e-mail HPI and request a new engine.
 
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actually the 4.1cm³ (0.25in³) the difference between the old Savage 25 motor and the new F4.1 is a new crankcase and upgrades to the cylinder, piston, connecting rod and crankshaft.

.21in³ is 3.4cm³. You must be thinking of the Nitro-star 3.4 ??
 
bnrpat09 said:
well i can guarantee, you need a new motor!!!
300's during breakin yells out to me "MOTOR IS FU**ED"
Click to expand...

It may have a bit shorter life, but 300 if only for a short period of time during break in does not necessarily mean the engine is fu**ed. So how can you guarantee this?


boody1981 said:
If my savage burbles away at full throttle I lean it out, if it dies out at full throttle I richen it up...temperature schwemperature...haha
Click to expand...

Temperature schwemperature? Also not good advice,

Temperature is important, if you are cosistently running your engines in the 300s they are NOT going to last. Although some engines do however perform better at a higher temp, I would highly recommend keeping the temps as low as possible while still making decent power, and making a nice trail of smoke. Use a temp gun to get an idea of where you are at, listening to burbles and waiting for it to stall are not good tuning methods.
 
Tune however you like, let me know how long your engine lasts. But waiting to "hear" blurbles or waiting for it to flame out I am guessing you will be "listening" to a new mill sooner than you think.
 
NCNITRO has it right on. Tuning does not have one variable but many. Temperature at the plug, Smoke emmission when applying throttle, Ambient temp fuel freshness, possible air leaks, and of course my favorite..common sense.

I am sure others will add to this list but it comes down to honing in on your skills for tuning.

Read up before adjusting needles back and forth. A little can go a long way in the right direction or clearly in the direction of a getting a new engine due to poor tuning.
 
I hear ya I hear ya. My truck is always tuned right to a tee, the engine runs very powerful and safe at the same time...all the time. I am very happy with this F4.1 mill and take good care of her. My truck runs as good as an 08 chevy.

P.S blowing up an engine...isn't that a good excuse to upgrade to a bigger one?

Cheers
 

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