FC350 Engine Noise

Id start with pulling the entire right side cover off and look at everything. Clutch cover removal isnt going to show a whole lot. If that checks out then dig into the water pump.

When I said clutch cover, I meant the entire cover. I've checked everything inside, water pump bearing runs smooth. The only thing that seemed odd to me was that the wp bearing is not an interference fit in the case and fits loosely in the bearing pocket.

I would think if your bearing is loose like you say then it could be bouncing around and causing the impeller shaft to do goofy shit.

It's not so loose that it falls in or out but it's not as tight as I think it should be. The pocket seems to be a hair oversized, allowing the bearing to be installed by hand with a bit of finnessing. It seems like it may have been built that way but then again, maybe not.

350 motors are just plain loud period... KTM 4ts in general are loud...

The new KTMs do have a bit of a tick to them. I thought the same when I went from my 2012 to 2016

CarlinoJoeVideo wrote:

The new KTMs do have a bit of a tick to them. I thought the same when I went from my 2012 to 2016

Does your '16 make that funky turbo whine sound?

Did you notice any change in the oil when you drained it? As in heavy metal deposit. It's usually a bearing going out with a whirring noise in my experiences

If the bearing was spinning when the motor was running I would think you would be seeing a lot of metal shavings in the oil itself as it ate away the aluminum.

Check and make sure youre getting enough oil to the head as there have been a few instances where people have gotten debris in their oil (dirt, water, etc.) and it has clogged oil passages.

KTMs are noisy though.

No, I checked the oil and both filters. The trans filter had a minute amount of debris which seems to be common. The engine filter was clean.

Does it look like your water pump bearing spun in the case?

MX915 wrote:

If the bearing was spinning when the motor was running I would think you would be seeing a lot of metal shavings in the oil itself as it ate away the aluminum.

Check and make sure youre getting enough oil to the head as there have been a few instances where people have gotten debris in their oil (dirt, water, etc.) and it has clogged oil passages.

KTMs are noisy though.

While changing the tensioner, I pulled one of the oiling jets out to have a look at it (be warned, getting it back in is a bitch) and it was clean. I still wondered about the rest though so I placed the straw on a can of electrical cleaner in the oil passage where I removed the jet from and pulled the trigger. The cleaner shot out of all the oilers so I considered those clean. Moved on the port for the cam chain tensioner and just like before, full flow. I then let it sit for a few hours to dry out, re-lubed the top end, installed new tensioner and that bastard oiling jet then bolted everything back together. Filled her up with oil and no change to the noise.

Casl616 wrote:

Does it look like your water pump bearing spun in the case?

It doesn't look like it has spun but the pocket has some marring in two 90deg sections opposite of each other due to vibration, oscillation, whatever you wanna call it. The other two 90deg sections still have tooling marks from machining.

Can you take some pictures?

I wish I had taken some, it's all back together at this point.

Oh dang. Well I guess all you can do it ride it and keep an eye on the oil for any unusual deposits.

Sounds like you covered all the usual suspects. Just curious, how many hours?

That's my plan unless someone with more experience chimes in on the subject. Something definitely seems amiss but I could be over analyzing the situation.

I'm sure you would know on yours. on my 16 350xcf. sounds different until I pull the clutch in. then it purrs. hope its nothing for ya.

Pulling in the clutch doesn't seem to make any difference on this particular ticking sound but I know what you're talking about.

CarlinoJoeVideo wrote:

The new KTMs do have a bit of a tick to them. I thought the same when I went from my 2012 to 2016

reded wrote:

Does your '16 make that funky turbo whine sound?

I haven’t noticed any turbo whining sound... maybe post a video?

I have seen two bikes that made noises that the owners did not like. Boke turned out to be the starter idle gear and starter clutch. Both times we fitted up some parts from a donor bike and the noise dissappeared. Both times we couldnt realy see any problems with the eye except that there was a tad more clearance you could feel. By holding one and moving the other you could feel.more movement on the noisy ones. Both times we showed it to the owners and put their orginal parts back in and they never had an issue. ( just the noise). Never heard that any issue cropped up. So maybe just a KTM Husky "thing".....

I would try using a mechanic's stethoscope with and without the metal sensing rod.

Done that, loudest near that wp bearing but the lower cam gear also runs the wp and is driven by the primary, so the noise could be coming from anywhere in that region.

Post a video to get a better sense of the issue.

Can't hear it unless you're riding it. I've even had my brother, who owns a '17 350, ride it and he can definitely hear the sound it's making but I can't hear it while he's riding it.

So it has to be in gear or under load or both?

Only does it in gear, while accelerating and decelerating until the clutch is pulled in.

One thing you can try is overfilling engine oil level (at least momentarily) and see if it drowns out the water pump or other bearings in the area.

Another question: the noise happens when the engine is warmed up or cold?