Buckeye Viper
New member
After over 7800 trouble free miles I've had my first break down. While sledding in the UP a couple of weekends ago that sweet sound of a triple changed and the sled was down on power. Unfortunately we were about 25 miles away from anything. Since the sled was still running I decided to limp it back in. Possibly my biggest mistake. After getting the sled home I pulled off the cylinder head and found #3 piston melted. I'm looking for opinions to whether I can just replace the cylinder and piston with out tearing the rest of the motor down and working on the bottom end. If you think this is feasible I plan on replacing all the rings and buttoning her up. If not I will probably look for a used motor.
Thanks for your help in advance. Tim
Thanks for your help in advance. Tim
Attachments
Last edited:
IMO too much metal went through the engine to not check the crank closely and possibly replace the seals. However, there are much better engine builders on here then myself so look for more input.
Maybe more important IMO is determining why it burnt in the first place. The continued running did a good job of masking the root cause, but I expect a lean burndown that let the rings and other debris fly around for quite a while. Might be dirty carbs or needles too low.
Maybe more important IMO is determining why it burnt in the first place. The continued running did a good job of masking the root cause, but I expect a lean burndown that let the rings and other debris fly around for quite a while. Might be dirty carbs or needles too low.
shaggyzr2
Active member
When was the last time the carbs were cleaned?
Buckeye Viper
New member
Carbs were cleaned right before this trip. We had already ridden over 500 miles in the previous couple of days without problem. Needles in stock position. We were on a plowed section of the trail with minimum snow. Temp light had come on but I couldn't get to any fresh snow. We were cruising at about 50 mph. After going thru a couple years worth of posts I assume it was a lean condition caused by the needle settings unless the crank seal went bad.
If you think that splitting the case and cleaning everything and replacing the crank seals will suffice I feel confident I can handle that.
If you think that splitting the case and cleaning everything and replacing the crank seals will suffice I feel confident I can handle that.
shaggyzr2
Active member
Sometimes you can flush out the crankcase but you're better off splitting it and cleaning it out, good idea to replace crank seals too.
drew24
New member
I too would split the case and check and clean everything really good. If it were me I would raise the needles in the carbs. A rear heat exchanger from a srx is also a good mod that would help if you don't have one already.
gonna need to split the case and likely the rod bearings will be toast on that cylinder riding it for another 25 miles blown up, beat and or heated the bearings likely. Vipers always blow up in the mag or center cylinder form lean conditions as you noted, the needles must be raised with todays junk gas. the rear srx heat exchanger is also a must on them.
Buckeye Viper
New member
Thanks for the info. Guess its time to pull the motor and come up with a rebuild plan.