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Sirio S27R Break-in

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Well, I started breaking-in my new S27R, run 4 tanks through her so far and heat cycling every half tank and running; HSN 7.5 and LSN 2.5. :cheers: Every minute or so, I took her temperature and she varied from 230 to 270 degrees F, she got as high as 300. When it hit 300, I shut her off quickly. It may have been a false reading as I checked again quickly and it read 280. Does anyone know if this is the mills normal operating temperature.

I'm running Trinity monster power 30% and the recommended plug, i.e. very cold plug. I know she's running very rich as she's sputtering thick plums of blue smoke. This should keep her nice and cool right??? The reason I ask is it was only 38 degrees today and it seems that the mill should run a little cooler. Any thoughs? :shrug:

I also checked the accuracy of the thermometer and it's dead on.

thanks,
Andy
 
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Take the LSN out a little.
Thats hot for break in. (300)
You might be rich on top but lean on bottom.
It wont hurt to richen.
Just my opinion.
 
Yeah, the lsn needs to be rich... you dont want performance yet... I broke my sirio .27r in partially, and it gets to about 230 or so and stays in that area. You may want to check for an air leak or something, maybe you didnt push the carb all the way in or something?
 
When ever I get a new engine, I air seal the carb. (Just in case)
 
I havent sealed my engine yet, because it has been working so well. I will do it next time it is out of the maxx.
 
Thanks guys, one more questions though...

The engine is now broken in but it still hits the 300+ degree mark. I checked, re-checked, and made sure the carburator is sealed properly, i.e. no air leaks. I know its still running rich as it still smokes nicely. I now have the LSN at 2.25 and HSN at 7.25 out.

I'm on my way to start fine tuning it now so I'll see what temp it hits when its tuned right. Maybe this is one of those oppisite engines that cools down when lean.
 
Never heard of an opp engine. Sirio carbs are really nice too. Try the pinch test...
 
Did you put sealer on the backplate and carb, because that is the only way you will know it is sealed right. You can't just "look" to try to make sure it is sealed, you actually have to do it. Is the head getting air past it? I switched my head to a nova head before i even attemped break in, just to make sure, and it got up to temp fine, but hasnt gotten over 240 yet.
 
I didn't think about the back plate... I will seal that too. As far as the head goes, I listened for air leaks but didn't anything. when slowly turning over with my fingers.

After I leaned it out today, it started running cooler, i.e. about 240 to 260 range. She really started to sing, man she was moving. I'm still fine tuning for perfect throtle response.

Anyway, have you had to adjust the MSN yet?
 
I have not had a chance to fine tune mine, because its not broken in fully, but it sure does get on the power band at about half throttle... wow.
 
I'm experiencing something unusual with the mill. I floor it from dead stop and it takes off as it should. Somewhere in the middle of its acceleration it starts to bog down abit but I keep it floored. it does this for a moment or two then continues to accelerate as it should. I'm assuming the problem is with the MSN but I have no experience playing with this needle, any advice???. Both low end and high are very powerfull but somewhere in the middle it starts to bog a little.
 
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