Strange noise in kenwood machine

it possibly stripped the coupler

sounds like the brushes need replacing
see link for them
https://www.partmaster.co.uk/chef-food-mixers/chef-range/km001/catalogue.pl?shop=kenwood&path=590704,71679&model_ref=440446&page=3

You are probably going to have to remove the top housing and look and listen while it is running. Does it lose drive when it is being noisy? You need to remove the back cover, the silver band with Kitchen Aid on it and that will expose the 4 screws holding the housing on. Remember fingers and tools OUT while it is plugged in or running. I can't be a lot more help to you, we don't have that model in NZ.

Try a company called e spares on the internet they do parts for a lot of items

Check that the nuts under the back cover at the sides have a bit of nip on them. It could be the armature polling on the fields. DO NOT OVER TIGHTEN THOSE NUTS.

Buy a new dough hook

Did it start clattering before or after it was re-greased? The K5ss by Hobart is an excellent mixer and there is no reason why it can't go on for a bunch more years. First you can get clattering if the brushes are less than 5/16th inch long, But that is not usual.

I would think that the rear bearing which is in the center at the rear may be more your problem, That bearing is behind the speed control switch and behind the governor (don't discount the governor being the problem) and is attached by two 3/8th nuts and slides onto the two guide slides that hold the motor parts in place. What i have found over the years is that 1.) the studs can bend (happens but not often) 2.) the bearing which is in the center of the big aluminum housing, (Called rear bearing assembly) moves over the years and causes humming and clattering.
So what to do about it? Loosen the two nuts a turn or two (do not remove) look at the top of the the bearing assembly and you will see a metal tab (used to attach the rear cover) (make sure the bowl and beaters are not attached to the machine) now plug it in and turn it to stir speed or number 2 position, put your finger on top of the tab and press down while the mixer is running, you should hear a change in pitch, and it should effect the clattering noise, (It will go up or down, or you may hear a new noise a light humming) (The humming is caused by the armature no longer in the center of the motor field and getting to close to the stator of the motor while it is operating, when it is out of center the developed magnetic field that causes the armature to turn gives off the humming noise because it is out of center or balance) if you notice that the clattering gets louder or softer by pushing down or pulling up you have to play with it to find the sweet spot, when you find it tighten the two nuts down just enough to hold it in place and no more. It takes a while and you wont hurt the machine but never go above speed two while doing this. If that fixes the problem you may have to do it more than once as the machine continues to age or if you move the machine around a lot. the real problem is the armature needs replacing (if this is the problem). Next you may have the machine timed wrong and that has to do with the speed control switch entirely, let us know what you find if these are not the problems we have a ways to go but they are the usual culprits with your symtom.

Not likely to be fixed because of no parts, buy a modern one. The gears are shot and it may wind up shocking you.

KAY – You don’t mention how long you’ve had your mixer or how intensely you use it, which would be helpful in assessing your question. Our first KA mixer we got in May 1989, seemed ‘whisper’ quiet compared to the replacement 6 qt Pro mixer our children got SWMBO for Christmas in 2006. The new mixer was so noisy that my wife called Kitchenaid to complain. The wonderful KA ‘Helpers’ explained that KA had changed to making all metal gears in their mixer transmissions as opposed to having one plastic gear (intended to fail instead of burning the motor out). That change from plastic to metal is then main reason your KA mixer seems to be much louder. You should be able to judge if your noise level has increased or stays the same during normal use. Since you stated that you don’t notice any overheating of the mixer I would say that the noise level is appropriate and wouldn’t be overly concerned at this point. That being said, if you hear a change in the noise level – usually louder, it could be indicative of mechanical issues in the transmission, which is what finally happened our mixer. One of the gear teeth broke and the agitator froze up. But that is another story…
I hope this helps. Good luck! Howard – Burke, VA
If this solution has helped you, please rate it, thanks!.hslincoln

waiting to speak to Kenwood 1st as we understand parts may no longer be available for this model. Thank You.