Broken engine, oops

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Anytime you have the engine apart it is always a good idea to put in new thrust washers also. They do break and is cheap insurance. If you have little to no run time on engine than maybe ok. But once you put a lot of time on it. Pitch them and put new ones in for safety.
 
Well engine is built, heat cycled and carb set on the rich side. Will do another heat cycle later today ready for bashing tomorrow.
It sounds strong and feels responsive but I won't know until tomorrow.
I'm also adapt to rebuilding pull starts now blasted things.
 
Just an update.

The KM engine is dead, the butterfly from the carb came loose and the engine ate it.

So when I ordered my 30 Degrees Truck I also ordered a new 30 Degrees 29cc engine for the Baja (badger). Its finally installed after a couple of weeks on the shelf, and I've heat cycled it twice this morning before work. So will have a bash at the weekend and get it ran in. It sounded healthy and think I'm starting to understand 2 strokes a bit after many many hours of YouTube and lots of Google.
Just for info of why I bought new engine, here's the costs for KM rebuild,
Carb 997 - £40
Head kit - £25
Bearings - £15
Bottom casting - £20

Complete RTR 30Degrees engine with carb - £130.

I thought it a no brainer to go with new engine, better castings and I'm not fussed on loosing 1.5cc, sooner have a screamer.
 
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KevTrem said:
Just an update.

The KM engine is dead, the butterfly from the carb came loose and the engine ate it.

So when I ordered my 30 Degrees Truck I also ordered a new 30 Degrees 29cc engine for the Baja (badger). Its finally installed after a couple of weeks on the shelf, and I've heat cycled it twice this morning before work. So will have a bash at the weekend and get it ran it. It sounded healthy and think I'm starting to understand 2 strokes a bit after many many hours of YouTube and lots of Google.
Just for info of why I bought new engine, here's the costs for KM rebuild,
Carb 997 - £40
Head kit - £25
Bearings - £15
Bottom casting - £20

Complete RTR 30Degrees engine with carb - £130.

I thought it a no brainer to go with new engine, better castings and I'm not fussed on loosing 1.5cc, sooner have a screamer.
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Can we see some carnage pics of the old engine?
 
Z.hb71 said:
Can we see some carnage pics of the old engine?
Click to expand...
I will get some in the morning Z, didn't take any as I was dismantling it. Was fed up with it so it got tossed into the scrap pile lol.
I will say I found the screw from the butterfly in the crankcase in the form of a 1mm shim, the butterfly plate itself was forced up the side of the piston skirt on the downstroke and dragged up with it.
I couldn't get it started for love nor money, plenty compression, good spark, plug was wet with fuel, anyways got it started and it revved its tits off, guess butterfly was just about off at this point, within 3 seconds of starting it stopped with a clunk so knew it was dead. I thought it was an air leak carb side, wasn't expecting what I found.
 
KevTrem said:
I will get some in the morning Z, didn't take any as I was dismantling it. Was fed up with it so it got tossed into the scrap pile lol.
I will say I found the screw from the butterfly in the crankcase in the form of a 1mm shim, the butterfly plate itself was forced up the side of the piston skirt on the downstroke and dragged up with it.
I couldn't get it started for love nor money, plenty compression, good spark, plug was wet with fuel, anyways got it started and it revved its tits off, guess butterfly was just about off at this point, within 3 seconds of starting it stopped with a clunk so knew it was dead. I thought it was an air leak carb side, wasn't expecting what I found.
Click to expand...
Yeah I definitely wanna see those pics ?
 
21bangbang said:
Wow, now thats a cooked engine. Look how poopy the port casting is. Looks like the surface of the moon.???
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A lot of what you see is swarf, I haven't cleaned the engine out etc of all the fragments, its just got tossed in the scrap pile. Fun learning curve.
cbaker65 said:
It looks like something got in there an chewed its way out!.....:unsure:
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Yup, the carb throttle butterfly pmsl
 
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