2002 Yamaha Bear Tracker - Lower Unit Clanking Noise

[Drenski]

New member here. This looks like a great website.

I've got a problem with my 2002 Bear Tracker. It's a long story so I'll try and cut it down.

I bought the Bear Tracker for cheap because it didn't run. I was told one of the valve rocker arms was broken. I pulled on the starter and it turned so I decided to purchase it. It was true, one of the rocker arms was broken however, after removing the head I saw the piston was at the top of the cylinder. I pulled the cylinder and the piston came off with it. The piston was a mess and had broken away from the connecting rod. Parts of the piston had fallen into the lower unit. I pulled the engine out and started the dis-assembly. It was all pulled apart but I couldn't pull the crank shaft apart without the proper tools. I also didn't like the idea of removing all the bearing pressed into the casings. I found a lower unit on Ebay for cheap but it was missing both sides. I bought it and after it arrived I took the entire mess down to the Yamaha dealer and payed them to reassemble it with a new piston and rings and a fixed cylinder. After getting it home and reinstalling it, it ran great. I was very happy however after it warmed up this clanking noise showed up. I took the bike back and the dealership went through what they had done but couldn't find anything wrong with what they did. This leads me to believe that there was something wrong with the lower unit part that I bought off Ebay. So, finally, my question is, what is in the central part of the lower unit that would make a clanking noise when warmed up. I can't see why a bearing would make a clanking noise or anything else in that area. Any ideas would be very much appreciated. Thank you, thank you thank you. Ps... believe it or not, this is the cut down version.

[oxidized_black]

sounds like a crank bearing, but wait for others to comment on this thread ...

[marioweldinginc]

Would you by any chance be able to upload a sound clip of the noise?

Sent from my SGH-T989 using Xparent BlueTapatalk 2

[Mudflap64]

Could it be something as simple as a skid plate hitting the frame after it heated up? Ire you certain the noise is coming from the engine? Try the stethescope trick to see if it's coming from one side of the engine or the other. I like Marioweldings idea, Can you upload a video with sound? That would help.

[Drenski]

I will get a sound bite up here soon and I'll look to see if it's a plate hitting the frame after it warms us. I towed my son and daughter on a sled behind this atv just the other day and I really didn't hear much of a noise. Maybe it was because I was distracted by driving or watching my kids in the sled. I don't know.

Thanks for all the input. This is great.