KDS-18 Intermittent DRAIN Problem

[ericp]

Hi all,
Just discovered this site, pretty cool. We bought a house around 7 years ago and it has old appliances and haven't had the money to replace so I continue to fix them. Old Tappan 24" double oven, and a Kitchenaid KDS-18, which I had thought about replacing many times but every time we looked at new ones, was not impressed, and slowly over the years have learned that this is a dishwasher worth saving, I know I could put a new one in that would last say 5-7 years, and this thing is 34 years old!! the owner still had the receipt from 2-2-1980, this baby was 460 dollars back then, with copper panel and right side panel since its at the end of the cupboards. Looking over the previous owner paperwork, on 4-16-1980, jus 2 months old, says unit won't shut off-just hums- checked unit-found bad gears in timer-replaced timer unit-OK. Then in 1997, unit doesn't start-repaired burnt black wire at selector switch and checked-OK. Then we bought the house in 2007. Couple years back, would not fill with water. I checked water level valve and eventually found the water fill double solenoid bad, replaced with newer one solenoid version. Recently detergent drawer won't open and every few uses it won't drain. I opened the front and the dispenser shafts had leaked onto the bimetals and rusted them, so I changed those to new metal plastic version and replaced O-rings, now dispenser is OK. I replaced the drain hose with new, checked drain solenoid for obstruction-OK. It still does not do the final drain sometimes, it might be every 4 washes or twice in a row. With 5 kids this thing gets used about 5 times a day, so it happens everyday. Since it works everytime if I press cancel drain, I suspect something with the timer, not the solenoid and pump. I don't understand why it drains in the previous cycles but not the very end?? Timer is around $100 on ebay, new number is 4162399.

Any advice would be appreciated.

IN the meantime, I looked on craigslist and drove one hour and picked up an older KDI-18 for parts, has a dial instead of all buttons, so timer is most likely not the same. That one also did not drain but the drain hose was clogged, tried it once and everything else seemed to be OK. Its a stainless look but no side covers.

 

[rp2813]

It sounds like the rapid advance timer on your machine may be the problem.  I think replacement is the only solution, but you should allow some time for the Hobart/KitchenAid experts to chime in.

 

The parts machine you bought will clean just as well, but lacks some cycle options your Superba offers.  Timers are not the same, but if you had to switch out the machines, the door and side panels from the Superba could be removed and used on the Imperial.

 

[combo52]

NON DRAINING KDS-18 DW

Most often the when this happens the DW is not draining well at any time and the water builds up a little each time the DW is supposed to drain to the point you sometimes have water left at the end of the complete cycle.

If it is really skipping just the last drain period it is likely a bad timer or intermittent drain solenoid on the drain valve [ try installing the drain valve from the KDI-18 on your DW ] It is fairly unlikely that it is the timer but possible.

The best way to figure out what is really happening is to sit through a full cycle and each time the DW goes into a drain period all the water should drain before the drain valve closes and the DW starts filling again. You can attach a test meter or light to the connections for the DV [ leads with insulated alligator clips ] and see if power is getting to the coil on the DV when the DW is supposed to be draining.

If you find the the pump-out is weak [ most likely problem ] you may have a restriction in the drain hose, air gap at the sink [ if you have one ] a bad DV or a worn or partly broken drain impeller in the main pump or possibly a piece of broken glass or other foreign object stuck in the drain pump housing area.

 

[ericp]

info update

Thanks for the replies so far, appears to drain properly everytime except at the end since for the rinse drains I can hear the solenoid click and hear water draining, and open the door and its empty. Seems at the end of the cycle the drain solenoid gets voltage and clicks open, but motor does not run, so there is still water from the last rinse but not soapy. Then it goes to dry and steams up, you can open and close and press cancel drain and that drains it every time. Is it possible there is something with the timer only at the end of the Normal Wash cycle that doesn't activate the drain but still opens the drain solenoid? I am trying to short wash in case its different but it looks like the cycle program is just abbreviated. Have to say there's some interesting engineering in this thing.

 

[barcoboy]

There should actually be two drain periods at the end of the final rinse before the dying cycle starts. The last four 90 second increments of the timer before dry should be, according to the service manual:

RINSE (WITH HEAT)
DRAIN
DWELL
DRAIN (SCAVENGER)

The main motor should stop at the DWELL increment for 90 seconds. I believe this increment was to give the dishes a chance to drip off excess water and so that water could collect in the bottom of the sump before one final pump out. The motor should restart during the last drain increment, and then 5 seconds or so later, the drain valve should open. After this final increment, the main motor should stop again, and the drying cycle begin with the blower starting immediately. Also, it is normal for the drain valve to stay open for 60 seconds of each 90 second timer interval, but whenever the valve is open, the main motor should also be running.