Why is my crank pin falling out?
I also posted this in another section but then came across the "Cen Racing" forum so maybe it'll be better suited here. Thanks for looking.
Hey guys. This will be my first post on the site and could really use someone's help. Just getting back into the hobby and this time I will be doing all work myself rather then paying an arm and a leg to the rip off artists (they actually just closed down) down the road to do all my work. I pulled my Cen GST 7.7 outta the basement for the first time in about 4 or 5 yrs! Everything is in almost new shape except the motor which just needed a new sleeve and piston and crank (crank has rust pitting). So I ordered a new crank housing, crank, piston/sleeve, and clutch (broke a spring removing one of the shoes)...... Everything arrived today so I figure I'd slap the parts on break her in and have it ready for bashing in the snow this weekend. Well didn't work out like that, which brings me to my problem. The new crankshaft I got isn't exactly the same, on the backside of the crank where the piston would be fixed to the piston there is a pin and spring instead of a fixed pin on the original. I put everything together all snug and when I went to fire up the motor and right as the motor would start to get going it would die and I'd loose grab of my one way bearing that turns the piston/crank. So I pull it all apart to find this pin fell out. Replace it and the same thing happens again and again and again, altogether I did this 11x with the last time ending with that pin tearing up my piston. Metal filings throughout the motor. I should mention I was using a drill as a crank for my roto start. Which I think I caused some damage by cranking to fast and long but it seemed the pin only fell out when the engine would just get going....... If anyone could help me out here I'd be so grateful!
I can post pics of this new crank compared to old crank if that would be helpful.