kielbasa
New member
Hey guys, last week while riding I noticed a slight tinking noise at idle - didn't think nothing of it until a while later I popped the hood and started listening closer.
It totally sounds like piston slap (teaspoon in a coffee cup), most noticeable at idle and completely goes away above 3000 rpm.
I mentioned it to my other riding buddy who also has a 2004 viper, he said "no way, can't be piston noise"....then he comes over and listens to it and says "wow, I think that's the piston!"
It's not loud by any means, but the noise is definitely there. I did not throw a gauge to check compression, but just going by arm feel, all three feel exactly the same.
Are these engines known to have their skirts collapse?
Sled has 6500 miles, so it's enough, but not a ton of miles.....was hoping I didn't have to tear into the top end until well over the 10k mark.
Anyone else run into this situation? Thanks for any info!
It totally sounds like piston slap (teaspoon in a coffee cup), most noticeable at idle and completely goes away above 3000 rpm.
I mentioned it to my other riding buddy who also has a 2004 viper, he said "no way, can't be piston noise"....then he comes over and listens to it and says "wow, I think that's the piston!"
It's not loud by any means, but the noise is definitely there. I did not throw a gauge to check compression, but just going by arm feel, all three feel exactly the same.
Are these engines known to have their skirts collapse?
Sled has 6500 miles, so it's enough, but not a ton of miles.....was hoping I didn't have to tear into the top end until well over the 10k mark.
Anyone else run into this situation? Thanks for any info!
sounds like the wrist pin is seizing up on it. seen it happen on a 340 and it destroyed the motor. i would tackle it sooner than later if possible.
mmordan
Member
I would pull the head and inspect the cylinders, pistons, and rings. While you are at it you can change head gasket to Opticool if you haven’t already... It seems to be a highly suggested mod on the Vipers. Look for any scoring on the cylinder walls, that will tell you if you have anything major going on.
kielbasa
New member
Update....the noise was not piston slap, but the wristpin bore on the center cylinder is bagged out.....most likely due to the extremely low oil consumption of this particular sled.
A couple of bucks
VIP Member
Better get that low oil consumption taken care of. 1 tank of oil/ 2 tanks of fuel is a good ballpark.
kielbasa
New member
ya...I checked the basics (cable adjustment, if the lever is intact and moving), everything looks fine so far...the cable was actually adjusted for a smaller gap than spec, spec is ~20.5mm, mine was at 15mm, which should mean more oil, correct?
besides, the damage is already done, engine apart, but i'll have to investigate further why it's not using oil...
besides, the damage is already done, engine apart, but i'll have to investigate further why it's not using oil...
One other thing to consider.
A friend just had a problem where the pickup coil came loose, and was bouncing off the magnets of the flywheel. Only could hear it at idle, then would go away.
We thought it was piston slap as well, but wasn't. Just pull the recoil off to confirm.
A friend just had a problem where the pickup coil came loose, and was bouncing off the magnets of the flywheel. Only could hear it at idle, then would go away.
We thought it was piston slap as well, but wasn't. Just pull the recoil off to confirm.
glad you found it before it got really expensive.