Hello,
I am trying to help a friend rebuild his yamaha blaster he purchased. To make a long story longer he had a clutch issue and got drunk and tore the whole dang motor apart….down to the crank and actually tried to press the crankshaft out
. I am rebuilding this tub of parts he brings over to me and have gotten to the point of putting the jug on the case. I am finding that There are multiple paper style gaskets and 2 metal spacer like plates. (I think they are aluminum.) I started with one gasket and tried to install jug and head. Well the piston hits the head and the crank will not rotate.
So experimenting, i found If i stack these metal spacer plates along with 2 paper gaskets, (like Paper Gasket, metal, paper gasket, metal.) i eventuallY get enough clearance to be able to rotate the crank without the piston hitting anything.
How do I tell if someone has changed the stock crank in this thing?? I know they previously deleted the oil pump, and the carb does not seem to be stock either. Its a KeiHin PJ.
I work on mostly 4-strokes so this is a lil new for me. I have a manual and have followed everything on the rebuild to a T. But I dont understand why they have all these spacers. Other than an aftermarket piston rod, like a stroker kit or something.
Seeing that I now have clearance enough that the motor rotates freely I finish the build pour some trans oil in the case and put the motor in the frame, kick it over a couple times to verify everything rotates smoothly, throw the carb on, put the spark plug on and kick it over. After about 3 kicks she fired up. It was running pretty nice, very responsive throttle. I started trying to figure out how to adjust the idle. Its a screw in style on the choke lever, (thats broken off
). As I blip the throttle I hear it bog up and then a rattle sound and it just died. I went to kick it over and could feel it was completely locked up. I pulled the head and jug assembly off and found the intake side of the piston skirt was destroyed and a million metal pieces are now in the case……. Please help me on what steps I should take to understand what I have going on and what could have caused this.
Thanks for your time and advice!
I am trying to help a friend rebuild his yamaha blaster he purchased. To make a long story longer he had a clutch issue and got drunk and tore the whole dang motor apart….down to the crank and actually tried to press the crankshaft out
. I am rebuilding this tub of parts he brings over to me and have gotten to the point of putting the jug on the case. I am finding that There are multiple paper style gaskets and 2 metal spacer like plates. (I think they are aluminum.) I started with one gasket and tried to install jug and head. Well the piston hits the head and the crank will not rotate.So experimenting, i found If i stack these metal spacer plates along with 2 paper gaskets, (like Paper Gasket, metal, paper gasket, metal.) i eventuallY get enough clearance to be able to rotate the crank without the piston hitting anything.
How do I tell if someone has changed the stock crank in this thing?? I know they previously deleted the oil pump, and the carb does not seem to be stock either. Its a KeiHin PJ.
I work on mostly 4-strokes so this is a lil new for me. I have a manual and have followed everything on the rebuild to a T. But I dont understand why they have all these spacers. Other than an aftermarket piston rod, like a stroker kit or something.
Seeing that I now have clearance enough that the motor rotates freely I finish the build pour some trans oil in the case and put the motor in the frame, kick it over a couple times to verify everything rotates smoothly, throw the carb on, put the spark plug on and kick it over. After about 3 kicks she fired up. It was running pretty nice, very responsive throttle. I started trying to figure out how to adjust the idle. Its a screw in style on the choke lever, (thats broken off
). As I blip the throttle I hear it bog up and then a rattle sound and it just died. I went to kick it over and could feel it was completely locked up. I pulled the head and jug assembly off and found the intake side of the piston skirt was destroyed and a million metal pieces are now in the case……. Please help me on what steps I should take to understand what I have going on and what could have caused this. Thanks for your time and advice!
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