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Can anyone tell me about the Sirio s12-t3i engines?

blue1

Well-Known Member
Joined
May 25, 2006
Messages
67
Location
Wenatchee
Picked up a Traxxas in a vehicle trade recently and I know nothing about nitro cars. Ive always been into electrics. Well with my car I got a few spare engines and one of them was the Sirio .12 engine. He told me the main shaft is siezed up but I dont see how. The shaft at the base turns and I can hear the motor turn over. The carb operates like it should to so I am confused what the problem was with this engine. Can anyone give me a little background info on this engine and tell me how to properly check it out for proper mechanical operation? Any help would be appreciated. I will not be running this engine because I am happy with the RB Concept v.12 engine and backup 2.5 I have on hand. I may sell this Sirio engine if I know it is working properly.
 
if compression is good fire it up and see if fuel leaks out the front bearing,when the bearing go to shat theyll leak.pull the piston and sleeve look at far up the piston will travel unforced to the top of the sleeve,if its getting close to an 1/8 inch from top of sleeve youve got a pretty cool paper waite.afterrun oil is youre friend with nitro engines,the nitro fuel is like brake fluid it sucks all moister from air,that could be what happened he didnt treat it after he ran it,built up alittle nap inside.hope this helps alittle .use alittle sealant on the bottom of the carb o ring also minute air leaks acure there in my experience.
 
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rockmike said:
if compression is good fire it up and see if fuel leaks out the front bearing,when the bearing go to shat theyll leak.pull the piston and sleeve look at far up the piston will travel unforced to the top of the sleeve,if its getting close to an 1/8 inch from top of sleeve youve got a pretty cool paper waite.afterrun oil is youre friend with nitro engines,the nitro fuel is like brake fluid it sucks all moister from air,that could be what happened he didnt treat it after he ran it,built up alittle nap inside.hope this helps alittle .use alittle sealant on the bottom of the carb o ring also minute air leaks acure there in my experience.
Longest sentence ever.:rolleyes:
 
I forgot to say speak in the way you would to a dummay. I know very little about gas rc's yet. So everything you said went up and over my head. but thanks for your reply.
 
I'll try to interpret ...

if compression is good fire it up and see if fuel leaks out the front bearing,when the bearing go to shat theyll leak.
start it up and watch the front output shaft for signs of leakage ...

pull the piston and sleeve look at far up the piston will travel unforced to the top of the sleeve,if its getting close to an 1/8 inch from top of sleeve youve got a pretty cool paper waite.
This is a test to see if the piston extends past that 1/8" of the sleeve if it does, then the motor was not properly maintained. (I've never heard of this "test", but does make sense)

afterrun oil is youre friend with nitro engines,the nitro fuel is like brake fluid it sucks all moister from air,that could be what happened he didnt treat it after he ran it,built up alittle nap inside.hope this helps alittle .
It's not uncommon for people to trash nitro engines by a lack of basic maintenance. They are air cooled, and lack any sort of internal oiling (other than what's in the fuel and the needed afterrun).

use alittle sealant on the bottom of the carb o ring also minute air leaks acure there in my experience.
This has bit me too ... if the carb leaks, the engine will never quite run properly, and worse, can lead to the motor running lean (and then burning up).

I'd say just start the sucker up and see how it goes.

Get some FRESH fuel (8%, and I've always preferred blue thunder). Adjust it to respond to throttle without a "bog" down. Let it warm up, then shutdown and cool. It should then restart with the same needle valve settings (if not, then it's probably an abused motor).
 
thanks for the dummy version. I will learn eventually whats what but lots of questions to ask the smarties for now. Thanks everyone for your replies.
 
sorry my reply confused ya blue didnt know you were that green,sounds like snow falls got a clue.I also pefer blue thunder,take good care of youre fuel keep it in a controled enviroment[dont leave in a cold damp garage or the likes]Just keep tabs on the engine temp as you run it,soon youll hear what the motor wants fare as carb settings just by listening to the engine as you excellerate.Also maintain youre clutch keep it clean inspect clutch bearing offten.Once you get more advanced youll learn the clutch is a tuning aid also.Glad to help bud good luck.
 
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