Bosch dishwasher motor relay

[notallbad]

Found the circulation motor pump relay stuck in its normal state so replaced it with a spare from my parts drawer.
Is the blue relay a suitable replacement?

What possible problems could have been caused by the relay being stuck in its normal state, in this instance normal state is running the motor via the 8uF starter cap.

Does the illustration on the white relay indicate its normal state i.e when not energised

[stj]

Re: Bosch dishwasher motor relay

i think the blue one is better.
try it - nothing to lose.

[notallbad]

Re: Bosch dishwasher motor relay

its already fitted but the motor is still not pumping fast enough to create enough pressure to turn the spray arms. the water alternates between top and lower arms but pressure is low to non-existant. can hear the water divertor running too and can confirm the mechanism is turning! the water pressure switch in the heating element casing does engage/operate

i think the motor windings are shorted.

at the motor cap i initially get 440v which then drops to 180v after the motor pump has started and the relay has kicked in switching over to 240v supply. i think thats whats happening!

also replaced the cap, no change.

[stj]

Re: Bosch dishwasher motor relay

have you checked there is no restriction or blockage in any pipes?
the other thing to check is the pump - does the rotor spin freely??

[notallbad]

Re: Bosch dishwasher motor relay

the blade doesnt feel loose and turns freely, both shaft and blade turns and seems to be on there tight.

have checked pipes for blockages i.e inlet hoses, drain hose and filling chamber/matrix but not yet inspected heating chamber or divertor assembly, the tub comes off completely on this model to gain proper access, bit of a pain.

[notallbad]

Re: Bosch dishwasher motor relay

I think stripping it down is the only way to be sure but having had another look at the motor, limited access whilst assembled, it would seem the impellor is in 2 halfs.

[stj]

Re: Bosch dishwasher motor relay

why not test it "stand alone" with a bucket of water and some lengths of pipe?

[notallbad]

Re: Bosch dishwasher motor relay

well it would seem the impellor is in 2 halfs. the impellor half has separated from the screw on rotor plate ( one half is blue and the other white, the blue impellor half has little lugs that locks into holes on the rotor plate, the lugs have worn down and no longer stays on the rotor plate properly)
it was kind of 'locked' into position but obviously when the motor spins up it was throwing the impellor off the rotor plate and possibly only sometimes locking into position

as a temporary measure I have glued the impellor to the rotor plate, blobs of glue on the lugs, put back together and hey presto, pressure back and spray arms rotating again!

replacement recirculation motor seal kit incl the impellor is £43 incl postage, (if that one fits my model) so that might be a good investment but will have to strip it completely down again, no leaks yet which is common when reassembling.

its a 15 yr old machine and the only problem we have had with it is the water matrix in the drain pipeways was gunged up around the pressure release valve but thats common on all machines with this design, or at least that I have seen so far, machines I have repaired in the past that is.
oh yes and then there was the recall repair but that was not an issue, done for free and before it caused a problem.
come to think of it, I may have replaced the heating element and replace a divertor plate from a tattt machine that had no resale value so parts used as spares at the tine.

WELL DONE BOSCH!!!!

Wont be spending £400 on a new one just before xmas, a big relief. i also wonder if bosch are still built as good. got this one for £310 in feb 2003 (i did get a £50 discount) so doin well and in pretty good condition externally still. not saying goodbye to her just yet.

[stj]

Re: Bosch dishwasher motor relay

are these "lugs" on the edge, or more inward?
maybe you can drill them out and put metal in instead - like grubscrews for example.

[notallbad]

Re: Bosch dishwasher motor relay

i did consider that but happy to settle for the glue for now, not sure if or how long it will last especially with hot water but may consider that if it fails again.

the lugs, theres about 14 of them, are actually on the fins so might not be possible

this is the only photo i took, stoopid me, should know better!

[stj]

Re: Bosch dishwasher motor relay

it almost looks like an epoxy, like it had the fins held in it while it cured!!