Bosch Dishwasher Water in Base

Re: Bosch Dishwasher Water in Base

Probably leaking in the back corner.

Re: Bosch Dishwasher Water in Base

I’ve managed to crack this problem; done loads; discovered the issues; fixed them……..none come back…all reported working OK. Machines will never leak on short cycles. They will only leak on the hottest longest wash (70 degree intensive) 15 minutes before the end of the cycle. That’s why leaks seem to be impossible to replicate on short test. The cumulative effect of several cycles will eventually trip the safety float switch. 😡 If you want to find the exact location of the leak, remove the plinth, panel behind, both sides and put folded kitchen paper across the entire base tray (easy to do) and run it on 70 intensive – it will leak from the rear left side 90 {e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} of the time.

Leak location 1. The leak will be on the air vent coming through the left side of the machine.

Drain down and remove all water from the sump and salt compartment. Remove body panels. Remove the air chamber (left side of machine) and clean the vent and lower nozzle (goes through the side of the tank near the salt cap). Reseal with heatproof silicone; the same stuff used for cooker door glass bonding. On inspection, the vent seal is the main culprit as it sits in between the chamber lip and the pressing hole in the stainless tank. It can move around and is rarely tight; in fact any amount of vent tightening will not stop it leaking. To fix it – run a small bead of silicone around the neck of the vent on the plastic chamber and set the seal into it. Then run a further bead around the outside of that seal. Don’t forget to put a token spread around the lower nozzle seal as well. Refit, tighten both the vent and the nozzle – no more leaks.

Leak location 2. Leaks showing around sump joint. Sump screws are always loose.

This loose fitting of the sump can lead to leaks on long hot washes.
Tighten all four screws in a diagonal pattern. It is not unusual to get 3/4 of a turn on each; but don’t force them. Then test with paper in the base tray. If it still leaks, new sump required. The place for leaks on the sump is usually around the diverter valve location; push a slither of paper on top of the ridge above the diverter to detect any water.

Leak location 3. Leak showing down the back of the machine from the tank to plastic base joining seal. Seal groove opens up around the back and sides – invariably seeps water into base tray.

These machines were the stainless steel tank and grey plastic base moulding types with the groove that the tank sits in. The screws at the rear corners and on the frame are always loose. A good repair of the joint seal can be made by thoroughly cleaning out the groove and filling it with heatproof silicone (same as mentioned above) smooth with a wet soapy spatula, pressing it in as you go. The air chamber will have to be removed to fully seal the left side of the tray joint; reseal the chamber as above.

Hope that helps!!

Steve.