GM_Man 47 #1 Posted January 29, 2015 Finally got around to opening up the 10hp Kohler on my B100 today. The previous owner said it made a horrible noise and he immediately shut it off and never ran it since. From what I can tell it only bent the exhaust valve and took a nice piece out of the piston. Can anybody tell me if the rod is a Kohler rod or not? I'm not thinking so becase it says Saint Bird on it. Share this post Link to post Share on other sites
Shynon 7,427 #2 Posted January 29, 2015 Not Kohler it is an aftermarket Share this post Link to post Share on other sites
Mr. 856 170 #3 Posted January 30, 2015 Please mind my ignorance but what failed? It appears the rod didn't break. Did it chew a piston ring? Piston get melted? Sure doesn't look pretty on top there. Share this post Link to post Share on other sites
WH nut 553 #4 Posted January 30, 2015 It chewed up something. Something went through the carb or got on top of the piston. I have had the top of a valve break off but never mad it to the piston. Share this post Link to post Share on other sites
GM_Man 47 #5 Posted January 30, 2015 Please mind my ignorance but what failed? It appears the rod didn't break. Did it chew a piston ring? Piston get melted? Sure doesn't look pretty on top there. It chewed up one of the rings pretty good and it almost looks like the piston got chipped up on one side. Hopefully I'll be able to get her going again! Share this post Link to post Share on other sites
WH nut 553 #6 Posted January 31, 2015 That damage can from the top, not the ring. Something went through the intake Share this post Link to post Share on other sites
Mr. 856 170 #7 Posted January 31, 2015 I am currently almost done with a 1971 Rotax 247(250) single banger for an old sled. The PO said he rode it around the yard last year......After I got it home I had every intention of redoing it anyway as this is going to be my sons future sled in approx. 10 years. Anywho when I opened up the engine I was surprised to see one side of the piston had a huge meltdown approx. the size of a quarter and chewed a few rings. Besides the look of your top my piston looked similar. I wonder what the heck could have been sucked up to do that to yours? If there was enough suction to pull say a small pebble in wouldn't there be enough force going out the exhaust port to maybe push it out? My guess would be that things are happening to quick to maybe exit? I am finding this all very interesting and am sucking up some responses from you more experienced guys like a sponge. I really enjoy this small engine stuff and really have learned a lot about engine operation and really what makes them tick in the last few years. Share this post Link to post Share on other sites
Mr. 856 170 #8 Posted January 31, 2015 Just found this picture I took of what I found.......... Share this post Link to post Share on other sites
WH nut 553 #9 Posted January 31, 2015 I am currently almost done with a 1971 Rotax 247(250) single banger for an old sled. The PO said he rode it around the yard last year......After I got it home I had every intention of redoing it anyway as this is going to be my sons future sled in approx. 10 years. Anywho when I opened up the engine I was surprised to see one side of the piston had a huge meltdown approx. the size of a quarter and chewed a few rings. Besides the look of your top my piston looked similar. I wonder what the heck could have been sucked up to do that to yours? If there was enough suction to pull say a small pebble in wouldn't there be enough force going out the exhaust port to maybe push it out? My guess would be that things are happening to quick to maybe exit? I am finding this all very interesting and am sucking up some responses from you more experienced guys like a sponge. I really enjoy this small engine stuff and really have learned a lot about engine operation and really what makes them tick in the last few years. Air cooled 2cyl are a whole different ball game. Wrong oil mixture or over heating will kill them in a hurry melting a piston to nothing more than an ashtray.I would like to see what the underside of the head looks like on the kohler. That would tell a lot more of the story. Just found this picture I took of what I found.......... 001.JPG Over heat on the exhaust side. 1 Share this post Link to post Share on other sites
Mr. 856 170 #10 Posted January 31, 2015 That is what I was leaning towards. Thankfully I personally have yet to blow up a 2 or 4 stroke. Share this post Link to post Share on other sites
GM_Man 47 #11 Posted February 17, 2015 Got the Kohler running today! It ended up needing a piston, rings, exhaust valve, and camshaft. https://www.youtube.com/watch?v=KdcJvxbpv0Q&feature=youtu.be 2 Share this post Link to post Share on other sites
Coadster32 793 #12 Posted February 17, 2015 Sounds good from the video. Nice work. Share this post Link to post Share on other sites