Time to play everyone's favorite game: Name that sound!

[RMK_SLED_TO_SKI]

Howdy fellas,

So I just picked up a 2005 RMK 700 last week. When I got it it idle'd a little high, but with the carb adjustment screw I got her down to a nice 1500-2k rpm real easy. Sled is in great shape body wise. Has decent compression (110 with a cheap tester), and fires right up (2nd or 3rd pull). Took it out once on Saturday and ran it about 15 miles. Runs strong. However, while I was out I noticed a noise at around 2500-3000 rpm. I can reproduce the sound by revving to near clutch engagement and then letting off. Then I hear a "click click" type sound. It doesn't always do it though. I wanna say its coming from the PTO side, but its hard to isolate. I put my hand over the VES and on the head to try and feel if the click corresponds to any noticeable movement and can't feel anything. I have scoured the forums and read several other posts which may be similar, but I figured this video would be a good place to get people thinking. Kinda like the good ol' days of Car Talk!

Thoughts?



You can hear it pretty consistently in this video.



at 0:04, 0:18, and 0:30



at 0:06 and 0:14

Thanks for playing everyone's favorite game!

 

[Betterview]

My hearing is not real good but I did detect a little clutch button rattle. Also it clearly sounds like you need to sink the carbs as it sounds like it is running mostly on one cylinder when the idle settles down.

 

[RMK_SLED_TO_SKI]

Any harm in pulling of the primary and running the engine without a clutch on? That way I can see if it’s the clutch making the noise.

 

[jrscirocco]

I have the same sled with 4200miles on it and have heard that same sound since I've owned it with no issues. The clutch has been serviced regularly and rebuilt once. The click sound didn't change IMO.

Otherwise, I have replaced a water pump at 2500 miles, steering post I broke + fuel pump & DET sensor at 4000 miles.

It has been very reliable in general. Enjoy!

Sent from my moto x4 using Tapatalk

 

[whoisthatguy]

Possible primary clutch swing weights rubbing on spider housing due to worn axle bolt or worn swing weight inside bearings. It could explode at any time. They also may require lubrication at those bearings. You also need new rings and perhaps the inside of the cylinder honed, because the compression should be in the 125 psi to 148 psi range. Also look for a torn engine mount at the front left. The VES guillotine valves should also be checked for stop damage, from impact against the cylinder.

 

[volcano buster]

Possible primary clutch swing weights rubbing on spider housing due to worn axle bolt or worn swing weight inside bearings. It could explode at any time. They also may require lubrication at those bearings. You also need new rings and perhaps the inside of the cylinder honed, because the compression should be in the 125 psi to 148 psi range. Also look for a torn engine mount at the front left. The VES guillotine valves should also be checked for stop damage, from impact against the cylinder.

All valid points. I had the guillotine washers go out on my '10 660 so worth checking and they made a similar sound.

 

[Jay]

check your exhaust valve springs.

 

[retiredpop]

All valid points. I had the guillotine washers go out on my '10 660 so worth checking and they made a similar sound.

Is that # 16 in the parts diagram? Exhaust valves
I've never even looked at those when I cleaned the valves.

 

[volcano buster]

Is that # 16 in the parts diagram? Exhaust valves
I've never even looked at those when I cleaned the valves.

Correct. Not something my dealer stocked so I had to wait of course.

 

[BeartoothBaron]

I'm not sure if I can help with what the sound is, but I've noticed a similar sound on my 600. It seems less metallic though, more of a muffled popping. Not sure if it's a different noise, or if it sounds more muffled because I usually hear it with the hood closed. It does it when the engine is winding down to idle; in fact, now and then the RPM hangs around 3000RPM for a second or two, and then drops down where it should be, almost always accompanied by that noise. I can adjust the idle screw richer and it never hangs, but then for some reason it idles like garbage and dies until it's fully warmed up. Anyway, I've gone through basically everything on that sled over the last four years without finding something that would cause it, and it's never let me down, so I just live with it.

 

[whoisthatguy]

The contact hitting noise comes when there is less pressure inside of the cylinder area, when the engine is winding down. Both the rubber VES diaphragms and the spring above them, work to resist the compressive pressure inside of the cylinder on the exhaust stroke. The momentum of the rebounding guillotine off of the top of the valve from the diaphragm and spring force, carries the guillotine in the direction of the stop. With less pressure inside of the cylinder area also working in the same direction as the diaphragm and spring, it appears that the guillotine makes contact at the stop hitting the cylinder assembly. This impact can flatten the guillotine stop and/or spray metal particles around inside of the VES valve area. Carefully examine the rubber diaphragm for tears around the washer, because as some point, that diaphragm works to keep the guillotine from impacting the stop. Replace the rubber VES diaphragms first, if no guillotine damage has appeared yet, imo.