• Welcome to RCTalk! 🚀

    Join the #1 RC community where hobbyists connect, share, and get expert advice on RC cars, trucks, boats, drones, and more!

    • Friendly & passionate RC enthusiasts
    • RC tips & troubleshooting
    • Buy, sell & trade RC gear
    • Share builds & upgrades

Sirio.18 Woes

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.

visioneer_one

RCTalk Racer
Messages
85
Reaction score
0
Points
0
RC Driving Style
Have a mate that just bought a Sirio .18 off eBay. We bolted it into his Sportmaxx and ran it that day. I seem to recall that the low end was unusually rich, and had to lean that needle in order to get it to start, but once it lit off it ran like a champ.

Two weeks later. The engine has become incredibly difficult to start. Once it lights it runs ridiculously hot at the top end (but runs rich at the low end), and will barely idle.

He's pulled the backplate and carb base and has sealed them with RTV. It appears to be leaking fuel around the front bearing... there appears to be a fine spray of residue in that area.

I'm guessing that might be the source of the lean top end. Doesn't seem like that would cause the rich bottom end, though.

He's also thinking that he may need to replace the piston and sleeve. Having to drop another $120 into an engine he's had for two weeks would SUCK.

Guidance?
 
Well - we called Trinity tech support yesterday evening.

(They only take support calls for one hour a day, weekdays only. WTF.)

The plug may have something to do with it. We were initially using the plug that came with the engine - whatever that was - once it died we replaced it with an OS #8. The OS plug is shorter than the recommended ones, and according to their tech-guy the engine will NEVER start with that plug.

We don't have the recommended Mc Coy plugs on hand, so that's a week of waiting.

I also suggested he go ahead and change the front bearing since its leaking.
Tip : the Traxxas 2.5 appears to use the same bearing as does the Sirio .18, and is far less expensive as a replacement part. Trinity wants $13; the Traxxas part is like $2.

I'm wondering if the piston and sleeve from a Fantom .18 can be used in this engine... just in case.
 
The bearing is in. The parts are identical - they even have the same OEM part number stamped on them!

We haven't had a chance to run it yet- perhaps later today.
 
Back
Top