thetorches
Member
Hello. My viper died on super bowl sunday. I checked compression and center cylinder was 15 psi. Other two are okay. Finally got around to removing head. Center cylinder scored. It looks like the piston was loose and hitting the head. Head has marks on it. When I compress the center piston you can here a clunck, like there is a space between piston and connecting rod. What could cause this. Could the piston pin have broken. First time doing this so any info would be appreciated. Thanks.
viperking
Active member
Rod bearing on the crank is gone.
thetorches
Member
I guess that meens the bottom end has to be done also.
Mac
Member
pull the cylinder off. Then you can confirm wrist pin & bearing or crank bearing failure.
yes, your lower rod bearing will be toast, youll need either a good used crank, piston, and cylinder or have someone repair the crankshaft assembly. Your going to need to pull the engine now. Very likely the bottom of the crankcase will have a pressure crack in it from the lower rod bearing failure.
thetorches
Member
thetorches
Member
Any idea the approximate cost of rebuilding the engine.
thetorches
Member
Thank you.
thetorches
Member
Removed cylinder and you were right. The rod bearing is shot. Don't know if it's worth fixing.
Mac
Member
Ebay has one. $500.
viperking
Active member
I have used parts available if you decide you want to fix it. Send me a pm and we can discuss.
if the sled is in nice shape they are worth fixing. you can usually find a used crank, and cases to repair, any other needed parts used then put in new pistons,rings,gaskets. they are still a nice machine but its common they blow up on the center and mag cylinders if the needles are not raised and richend up.