2018 XC300 horrible sound?

[swazi_matt]

Can't help, but love the expression on your son's face at the end!! such a typical "... why are you bothering with this, it still runs, we could be riding...??" look

[Davehuge]

Originally Posted by swazi_matt

Can't help, but love the expression on your son's face at the end!!

True...

[dzhitshard]

LOL,

The video is doing the WHOOMP WHOOMP cyclic sound and vibration little justice. Especially when I was so frustrated I laid on the pipe for a solid 100yds just trying to see if I could make it let go.

That's my riding buddy's kid. He actually said something like "Holy crap, I thought that thing was going to explode coming down the logging road. What's wrong with it." My kid was gone by then but he was definitely the whatever, lets just ride guy.

[Davehuge]

Hopefully it's not too serious, won't cost too much time or money to fix and you'll be back on the trails again soon!

Keep us updated, all the best, Dave.

[dzhitshard]

https://youtu.be/jL41A1P-FOc

a bit clearer audio of the noise. Found it after another sleepless night.

[Davehuge]

Pull the power valve cover off and the exhaust off to see what's happening.

Good luck, Dave.

[RudolfHucker]

I have heard of excessive side to side play in the powervalve that can be fixed by just shimming up. The power valve linkage has an adjuster on the top. Adjust until the linkage just fits smoothly on the end of the power valve shaft with the valve fully closed. Also check that the wire retaining clip is still securely in place. If not, either clip it in properly or go looking for it if it ain't there! Most likely place is down in the engine and that's not ideal!

If all looks well, use a metal rod or screwdriver against your ear to try and locate the source of the noise. Move around the main sections of the cases sucb as clutch cover, crank ends, water pump, flywheel etc. Water pump shafts have been known to shear off or wear really badly causing the impellor to catch the inside of the casing.

Just try not to touch the HT lead. Not good but will clear stubborn ear wax.

[Motorman_55792]

If you feel a vibration with it, stop riding and tear into it.
My thoughts are loose nut on flywheel or clutch basket, or maybe the old problem of crank stuffer bolts coming loose, but in this case not locking the engine, just hitting the rod on each rotation.
Just thoughts to check... Good luck and let us know what you find!

[eralha]

wow... that is nightmare fuel! hope you find the issue, keep us posted. good luck.

[Gibnut]

Not sure what the noise is, but the pv arm lock nut was backed out all the way on my ?18 EC250 after about 10 hrs.

Whip the pipe off & have a gander behind the rhs pv cover to be sure.