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Discussion Starter #1
I drove it about a quarter mile yesterday and noticed it was smoking a lot and it finally make a clunking noise, lost power and died. After that I couldn’t budge the pull start. Took it home and pulled off the belt cover and that was fine. Pulled off the starter cover and that was find. I was finally able to get it unstuck by hand. It would turn a bit but not 360 degrees as it would hit something inside. I think I higher have a broken piston rod. Do you folks agree and how hard is this to replace?
 

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Your rod is most likely ok, but the piston is probably junk. Not terrible to replace. You are gonna want to get a repair manual for it and follow the instructions. There are some that are Electronic or paper. I like the Clymer and Haynes manuals. About 30 buck. Rebuilt my first 325 engine following the instructions. All of the intake has to come off along with the exhaust so you can free up the cylinder which can be taken off with the engine still in the frame. You will have the cylinder measured and a new piston fit. And while you take it apart do a forensic kind of exam and figure out the reason it failed. The most common is lack of lubrication. Oil pump failure isn't common, but the lines coming off the tank the pump is.
 

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Yeah. The spark plug was bone dry so it the oil may not have been feeding it properly. Thing is. It was idling for about 15 minutes while I loaded up my ice fishing gear. Died while driving. I have a guy lined up to give me an estimate on repair this week.
 

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Idling is bad - smoking is good - probably seized a piston like stave said, but there is the possibility that the lower rod bearing failed and the piston might be fine - definitely have to get it apart to access the damage - note; don't let the engine idle more than a couple minutes - my rule is if it is going to idle longer than it takes to pee, shut it off.
 

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Yep, that will stop it from running all right. Were you able to get all the extra pieces out of the crankcase?
 

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Typical of a two stroke with excessive piston to cylinder clearance combined with insufficient lubrication which can be aggravated by alcohol blended fuel if the oil being used will not mix with alcohol. Use compressed air to blow the shrapnel out from the bottom of the crankcase and from around the crankshaft. Inspect the lower rod bearing for small pieces lodged in the lubrication slot. Real small pieces (head of a pin and smaller) will not cause damage and will be expelled as the engine is run, but regardless of size, the more pieces you get out the better it will be for the moving parts.
 

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I notice it broke on the intake side - what condition was the air filter in?
 

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Discussion Starter #9
Air filter looked fine. I have a guy working on it now. He’s going to go through it pretty good and replace seals, piston, gaskets, air filter, etc.
 
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