My 1996 scrambler has a rattle sound coming from the engine. Please take a look at this video.

http://www.youtube.com/watch?v=oC3gHFRszeI&feature=youtube_gdata_player

The video is with the clutch on and I went to the Polaris dealer by me and bought a clutch puller. I removed the clutch and the rattle noise is still there. It almost sounds like a bolt in a coffee can or something. Could it be from my starter or recoil? I notice when I use the electric starter it make a rattle sound very similar to the rattle in the video.

Any ideas on where to start? Thanks for any replies.

 

things that can make bad noise.
bad rod bearing or wrist pin bearing
collapsed piston causing excessive piston clearance.(slap)
counterbalance area is probably the first place to look, drain the oil.
see what color it is.

I have also had rattles from the recoil area, I think the starter drive(bendix) rattles.

But I would like to hear it without the clutch.
you need a stethoscope to help you pin point the sound.

 

Can I pull the recoil off and pull the starter bendix out, replace the recoil and start it with the pull rope? That way it would eliminate the bendix if it's rattling?

 

Yes,but if its 400 2-stroke you have to pull flywheel to remove bendix. My bet is the noise is piston slap as mrtwostroke mentioned!

 

Is the stock bore listed in the shop manual? I'm at work so can't check it now. He just put a new piston in before I bought it so was hoping it wasn't that. What would a dealer charge to look at it roughly ? Ad would they be able to tell for sure if that's it? Thanks again .

 

you can pull the bendix out the back. once the starter is off. which can be done with clutch cover on. just harder.

 

83mm new piston may have been pointless, if it wasn't rebored.

 

It was rebored .020 over he said. It also has a Wiseco piston in it. He put a new exhaust on it and ran it lean and burned a hole in the piston. What is the maximum oversize bore you can do on these? Are they sleeved? I really appreciate your guys time and help. What would be the best way to check if its the cylinder? Dial caliper to check for runout?

 

Well good news sort of. I got the starter out with the bendix and started it with the pull rope and the noise was still there. I do not hear the metal rattle now that i got my exhaust off. I was going to paint it anyway but it was leaking by the exhaust manifold ( missing a spring) and also leaks back by the silencer ( both springs are there but are real loose). What a waste of 4 hours. Now I do have a few more questions.

1. It's a DG exhaust. Can I get any spring as long as it's tight?

2. How the heck am I supposed to get them on? ( had a heck of a time with getting the one of the exhaust manifold off and can only imagine I'm going to bust some knuckles getting them on)

3. I need to get the top bolt in for the starter and don't mind pulling the clutch but do I need another tool to pull the other clutch off?

3. Lastly what is some good oil for the chains? I heard WD-40 dries out the O-rings?

Thanks for all your time guys, as I know no one here has to help me but you all do and for that I want to say thanks again.

 

I wouldn't even worry about the other stuff right now,if slap is still there,I would pull cylinder and check piston. Very easy way to check for wear is remove piston from rod,remove rings, install piston in from cylinder bottom,hold bottom of piston flush against bottom of cylinder and insert feeler gauge on opposite side,if over .004-.005 clearance at bottom of piston to cylinder,TOO much! If wears too much will break piston skirt and cause more damage. Yes they have a liner,if bored out to max,can reline for about 125 bucks. OPT