New rebuild problems

[2strokeRidr4Lfe]

Ok I am completely mostly lol clueless on what in the world happened to my piston. I have an 01 engine me and a friend rebuilt did everything by the book fires up revs up and all. Took it out to break it in rode maybe 2 hrs tops off and on like 10 to 15 mins riding cool down then again so on, even put throttle limitter most of the way in. Now when we were breaking it in it was acting like it had no power running and pushin me with a little rpm but no where near what it should. Found out it was gettin oil into the crank side of the case and burning it off into the exhaust now I'm almost positive this was the issue for the bogging and having no power when we tried to break it in but please correct me if im wrong it. My question is why in the world did the first time we took my head off after idle for about a half hour total checked the piston and everything looked nice. Now after we found out that it was burning oil we were tearing it down again to reseal the case with yamabond and we took the jug off and my brand new wiseco piston looked awful! It has the tiniest but def fealable gash on the side of the ear and in some spots around the edge of the top of the piston are like dented real slightly. The top of the piston has really small dots all over it looking dead on the imprint thats on the head where the piston meets it. Please tell me are the dots normal and what in the world could have caused the dents around the edge of the piston the little gash looks like somethin came in from the reed cage but the piston rings are perfect not at all messed up and the cylinder wall is still perfectly smooth from fresh bore oh ya its been bored 80 over for 80 over you dont need any head work do you? i just dont get it please help! lol this rebuild has been drivin me crazy with the little bs going wrong

 

[super noober]

can you post some pics? a piston dosent just scratch itself, there must be something in there.. i dont think a broken reed could do thta but check them anyways. is there a chance this motor has been blown up and there was still pieces of piston down in the crank case that could have been worked into the cylinder? really weird how the cylinder wall is ok but the piston is scratched..

 

[yb200]

crank seal .

 

[2strokeRidr4Lfe]

Ya I will definately get some pics for you guys thanks for the response too... And ya your right I didnt even think about what you said about being blown up before and loose pieces possibly still in the case. Yes it has been blown up before bottom crank rod bearings went out because the way one of my friends rode it, not knowing what he was doing and acting like he did locked it up. But ya thats 100% definately a possibility because when we had the case apart i didnt want to spray the case out with anytype of degreaser and if i use water it wouldnt of done anything so i used shop rags and cleaned it to the best i could but there were still some small dirty spots that could of had a piece of that rod bearing still in it. Even though thats a small gap to fit something between where the oil was leaking into the crank but is possible cant say it isnt or there was a little gash at the bottom of the crank side of the case where the rod hit it when it blew up that might have worked a piece of that too... Sucks but ya ill get some pics of the piston and the cylinder wall and head later today its at my friends house probably gonna bring it to my basement and rebuild it again any suggestions on what to clean the case and all inside parts with? Oh ya I forgot to say that we put all new quadboss oil seals in it during the initial build.

 

[jjj_85]

Just curious, but why wouldnt you use a degreaser or solevent in the case? Brake clean works fine, so does about anything else? To be completely honest your not supposed to use any kind of rags that can leave fragments behind. Brake clean is your friend.

 

[2strokeRidr4Lfe]

OK thanks to all the very very very very very very very helpful advice. Cleaned out the case really good bought some Yamabond 4 and sealed the hell out of it. Turns out the clutch ball we had originally lost in the initial tear down about 6 months ago found its way into the cylinder X(. But Cylinder walls and head turned out to be perfectly fine . I found the ball stuck in the slot on the bottom end of of the crank rod I was so pissed, looked like somebody took a shaving razor to it 30 times. But got new gaskets put the motor back together and after clearing up a carb problem she's runnin bad ass now! (Carb problem was engine was gettin to much gas would run bad ass with fuel on off switch half way on. Slapped a new float in and vaola back in action again!) Btw my new pic is my 05 blaster with my 01 .80 over engine on it the engine we were talkin about in this thread.