Kitchenaid Blender - Stopped working

[finocencio]

Hi,

I´m a new user at this fórum and I´d like to know specs about a componente of control board Kitchenaid Blender.

The blender is 110v but accidentally was turned on in 220v and component MDV1 blowed up. It´s a varistor wich spec I couldn´t find.

In another forum I´ve found the diagram but no have a spec about this component.

If somebody could help me, I´ll thankful.

Regards.

[Armadillo]

The Varistor is from Maida;
Replacement part can try:
https://www.ebay.com/itm/20-pcs-D6944ZOV181RA09-MAIDA-14mm-ZINC-OXIDE-VARISTOR-180VAC-ROHS/121440886940?epid=1827580957&hash=item1c4670e09c:g:vs8AAOSw-jhUG9s2

[finocencio]

Thanks for your help !!!

Best Regards

[Bashstreet]

Yes i believe Armadillo is right looks like input varistor should be easy to replace.
 

[helius]

Someone else made a thread about an identical unit a couple years ago.
https://www.eevblog.com/forum/repair/kitchenaid-blender-repair/msg986855/

[Armadillo]

Yes i believe Armadillo is right looks like input varistor should be easy to replace.
 

You know I merely answered his specific question on the specification of the varistor.
I suppose he checked the rest of the circuit.
He said in another forum he found the circuit!

In another forum I´ve found the diagram but no have a spec about this component.

Regards.

[james_s]

A couple years ago I fixed a Kitchenaid mixer, at least I think that was the brand. The fancy control board had failed so I spent some time reverse engineering it then realized I could buy a new board for $25 so I did that instead, spent my limited time on more interesting projects. Have a look and see if a new board is available.

[oldway]

It's a bit off topic, I apologize for this, but it's about another Kitchenaid product, the Kitchenaid food processor.

I would like to show how a good idea in theory becomes a very bad one in practice. 

Here is how a (excellent) Kitchenaid kitchen robot ends up recycling because of a US $ 10 replacement part .... !!!!

To avoid overloading the motor, the Kitchenaid engineers had the idea of replacing the metal gear-worm with a plastic one.
The idea was that in case of overload, the plastic pinion would be destroyed and protect the motor .... interesting idea in theory, but catastrophic in practice.

Since the cost of labor is so high in Europe and the repair is not that easy, most of the owners of this device do not repair the faulty device and send it to recycling.
https://fr.ifixit.com/Guide/KitchenAid+Classic+Mixer+K45SSWH+Worm+Gear+Replacement/31411
https://www.amazon.fr/Kitchenaid-4162897-KitchenAid-4162897-Remplacement-Gear-worm/dp/B014W9G3NC

This plastic gear-worm causes a lot of unnecessary breakdowns and makes the device unreliable ..... a very bad idea indeed  ..... 

[Armadillo]

Would the change be more on Hygienic Concern, example micro pits/cavities of metal worm gear?

[cowana]

Also due to noise - plastic gears are usually significantly quieter than metal ones.

[PrecisionAnalytic]

Would the change be more on Hygienic Concern, example micro pits/cavities of metal worm gear?

There seems to be the business model of making anything that was once metal, with plastic to save on expenses.  I want to say the practice started in Great Britain in the 60's or earlier

I have a Kitchenaid professional 600 that I picked up for around $100 and had to tighten some bolts which adjusted the gears (metal) thankfully was all and works great.  I did clean up and lubricate with food grade oil as was leaking with like you noted... potentially metal in the lube.

[oldway]

No, it's just a weak element in the transmission intended to protect the motor against heavy overload.
The first models had a metal gear and were almost indestructible .....

Hygiene concern: It seems to be nylon reinforced with fiberglass...not particularly healthy product.

Noise: a well lubricated metalic gear-worm is not noisy....In every case, the universal motor used in this food processor is far more noisy.
I know very wel this device because I already repaired some of them....It is a pity to see people who decide not to repair them and to get rid of them by recycling....

EDIT: explanation found on Internet: The nylon gear is meant to function like a fuse in an electrical system: an overload (super stiff dough) will chew up the relatively inexpensive nylon worm gear instead of burning up the pricier motor

[Armadillo]

Hygiene concern: It seems to be nylon reinforced with fiberglass...not particularly healthy product.

I wonder what are those intravenous apparatus are made of, things like syringe, blood pump etc.?

[helius]

IV pumps are peristaltic type. Only Tygon tubing is in contact with sterile fluids.

[oldway]

The problem is rather the ingestion of particles from the destruction of the gear .... Ingest nylon particles with fiberglass does not seem very good for health ....
I think grease should be replaced too.

[Paul Moir]

Forgive me if it's obvious, but how does the nylon gear end up inside your food?  Is the gearbox open?

I wouldn't be surprised if it was.  Coming from industrial sanitary design, I find kitchenware appliances design shocking.

[PrecisionAnalytic]

I think grease should be replaced too.

I'm thinking when I get around to, I can use a thicker "grease" versus the oil I used.  Wondering if a refined coconut oil will work?  Any suggestions for optimization?

[james_s]

I would use whatever lubricant the manufacture specifies, I tend to assume they knew what they were doing in that regard.

I don't know about coconut oil, but vegetable oils tend to go rancid and also get sticky/gummy with time.

[tooki]

There seems to be the business model of making anything that was once metal, with plastic to save on expenses.  I want to say the practice started in Great Britain in the 60's or earlier

I'm sure that cost-reduction occurred everywhere at a similar time, since the manufacturing and materials engineering progressed similarly.

Regardless, in the case of KitchenAid, they damned well didn't do it to save money. If they wanted to do that, there are far more frivolous expenses in a KitchenAid (like the die-cast zinc top case, which is massive despite not being load-bearing except at the very front; it'd be easy to replace most of that with a cheap plastic molding). I wouldn't even be surprised if the nylon-over-steel gear they use is more expensive than a solid sintered steel one would cost.

The problem is rather the ingestion of particles from the destruction of the gear .... Ingest nylon particles with fiberglass does not seem very good for health ....
I think grease should be replaced too.

The grease is so thick, there's normally no path for the grease to exit into the food. But he mentioned the grease has leaked oil, so the grease definitely needs replacing.

Forgive me if it's obvious, but how does the nylon gear end up inside your food?  Is the gearbox open?

I wouldn't be surprised if it was.  Coming from industrial sanitary design, I find kitchenware appliances design shocking.

The gearbox is not open and is packed with heavy grease, which normally stays put. But with advanced age, the grease breaks down to oil, and this oil can find its way out.

I know exactly what you mean about kitchen appliances having terrible sanitary design — all sorts of gaps and ribbing and holes for stuff to get into, with no way to clean. It's something I pay attention to when buying. (And one of the things I like about my KitchenAid blender: very few gaps. Membrane over the buttons.) If you have time to watch the video below, I'd be curious as to your impressions of the KitchenAid mixer's design in this regard.

I think grease should be replaced too.

I'm thinking when I get around to, I can use a thicker "grease" versus the oil I used.  Wondering if a refined coconut oil will work?  Any suggestions for optimization?

There are tons of KitchenAid repair videos on YouTube, since those things are built to last. Watch some: the grease is spectacularly thick (like heavy vaseline). The oil that leaks from very old KitchenAid mixers is the grease decomposing. No, you can't use coconut oil. It's far too thin. The heat from friction alone would cause it to turn completely liquid and make a gigantic mess — not to mention provide no lubrication to speak of.

I want to say that I remember reading the original is actually a food-safe Shell grease, but only sold in 55-gallon drums. But luckily, there are parts vendors that break that down into small containers for individual repairs. It's trivial to find on Amazon, etc: just search for "kitchenaid mixer grease".

https://www.amazon.com/Kitchenaid-W4176597-Original-Equipment-Manufacturer/dp/B00OSC174E


Here's a good repair video for a "regular" kitchenaid mixer:




ifixit has a repair guide for the professional 600: https://www.ifixit.com/Device/KitchenAid_Professional_600

I would assume it uses the same grease.

[PrecisionAnalytic]

I would use whatever lubricant the manufacture specifies, I tend to assume they knew what they were doing in that regard.

I don't know about coconut oil, but vegetable oils tend to go rancid and also get sticky/gummy with time.

Right, good call.  Not sure what I thinking at the time. 

Thanks for the link tooki.

[SeanB]

The grease you are looking for is Shell Cassida, sold in 20kg drums or 210l drums, though there are also plenty of places that package it in 400g grease gun compatible tubes which are a lot easier to get. Try almost any bearing supplier, they tend to have the grease on hand to go with the stainless steel bearing ranges. Remove all the old grease, wiping it off of every part, and wash the metal parts and housing with some degreaser and a brush to get it all away, and then use the food grade grease to repack the gearbox, around half grease and half air works well.

A little of that grease goes a long long way, still have half a drum of it, even though I use it as a general purpose white grease a lot. Water resistant and tends to stick very well to parts.

[tooki]

KitchenAid grease isn’t white, it’s brown, so it’s almost certainly different from what you’re suggesting. But as I’ve already shown, it’s easy to order the right stuff.

(And I’m not sure that “a little goes a long way” is the right advice. The KitchenAid gearboxes tend to be liberally greased at the factory, and that’s how I’d do it if repairing it.)

[Marco]

No, it's just a weak element in the transmission intended to protect the motor against heavy overload.

It's just weak competition. If they had real competition the plastic gear would be rightly seen as poor quality and they'd spend the few man weeks on protecting it electronically, which has been the correct solution for decades.