Q: "This valve utilizes a rubber diaphragm attached to an metal plunger to gate coolant entry."
The explanation works so well I hate to be picky, But, the diaphram is just a flexible seal and IS NOT a part of the water control function. The valve seals on the half inch dia. rubber seal at the tip end. I would love for someone to explain the screen function as that also isn't where the water flows.
The main reason I point this out is that one of the most common failures does occur when the diaphram tears. That problem is a lack of heat or more precisely a heater that heats and then quits after a few miles. I have heard some good explanations why, but the one that keeps my memory is that the coolant gets behind the piston and the pulsing in effect jacks the valve closed.
BTW the monovalve capsule kit is MB# 000 835 06 44, Bosch# 1 147 213 007 MB list $35.
Owner 24 bay BSC
Bosch Master, ASE master L1
26 years MB technician
[This message has been edited by stevebfl (edited 03-31-2000).]