son7771
New member
My son pulled it of trailer and let it idle. I was standing there and it had been running for 45 seconds or so. Then I heard a sort of pinging, scraping and it started to idle rough. Pulled spark plug and it has zero compression on the pto side!!!! Now i have not taken it apart to see if cylinder is toast but what could cause this? I have some ideas but i never had any problems with a sled lots of mx bikes!!! Could it be crank seal and how can i check before disassembly? I was told that they were aftermarket pistons "wiseco" I am running stock jets but i did take off the aeen pipe but the kids did drive it around the yard after that! could the rings have not seated right and finally let go? any ideas would be cool thanks I will be tearing into it this weekend!!
daman
New member
Hard to say, just open her up.
son7771
New member
got it open looks like something went thru the intake. Must have happened when we cleaned carbs and changes jets? So now i am looking for a pto side head as it is all dinged up. Cylinder is fine but am getting it honed anyway I do have one a cylinder coming anyway as i found one on ebay. If anyone has a pto head and woould like to sell it pm me please thanks
daman
New member
should be able to find everything on ebay, always see lots of PZ stuff.
PZ 1
Member
- Joined
- Mar 12, 2005
- Messages
- 987
Make sure that there isn't still something laying in the crankcase. Did you lose anything when you did the carbs? Check for something missing there. What do the marks in the head look like? The foreign object might be in the muffler.son7771 said:
son7771
New member
I dont know what i could have lost there is something in the exhaust i cant get out. I had a few projects going on at the same time in the garage. My son was doing some of the work also. The marks a traingular looking and the rings and piston are in one peice so i really dont know. there could have been something in there before as i only had this sled for on month and the only time it was used is around the yard mabey 1 mile since i owned it. But my guess is i dropped something in there as i was frustrated that yamaha made it difucult to take carbs off (that was until i figured out to just take secondary off and it became much easier!!!) The one thing i didnt check yet is the wrist pn bearings but the pin looks good. Oh well the kid is getting a good lesson in rebuilding motors and we can spend good quality time together. Thanks to all on these forums as they become a great source of answers and if you do a search there is a forum on everything.