W126 Heat issues - PeachParts Mercedes-Benz Forum

Solid Snake · #1 10-08-2010, 04:27 PM

Hey guys,

My car thus far has been great lately; except for now that it's getting colder outside, I like the car scorching hot.

I have adequate heat with max settings when in town, but on the highway cool air is blown from all vents.

I am suspect a few of my pods are busted (driver foot flap, defroster vent), but do these affect my heat?

I've read nightmares about replacing these pods, but are any of them easy to get to?

Thanks again, oh might Benz oracles.

-Carlen

Gilly · #2 10-08-2010, 08:12 PM

On a 126, any heat complaint I would immediately check for a torn diaphragm in the mono-water valve.
Gilly

Solid Snake · #3 10-08-2010, 11:43 PM

That's what I was thinkin' based on my forum search. Looks pretty easy too, thank God.

mak · #4 10-09-2010, 02:07 AM

yes most likely its the mono valve .
as you mentioned it gives heat in city and not on highway driving also replace the thermostat.It may be failing . Thermostats also have a finite life and wear marks are visible on the side the bellows operate
mak

Solid Snake · #5 10-09-2010, 02:11 AM

I was also suspect of that sucker too, as my coolant temp gauge has been pretty goofy lately, jumping all over the place and what not, then return to norm.

The monovalve is definitely in my DIY range; what about the thermostat?

Thanks again,

Carlen

Gilly · #6 10-09-2010, 04:43 AM

Should be able to handle it, not as easy as some engines though.

mak · #7 10-09-2010, 10:31 AM

raise the front of the car when re-filling the coolanrt ,this will bet rid of the air in the heater and pipes or you may get erratic temp readinds or worse over heating at low speeds. better than purging it at the bleeder .
mak

SD300 · #8 10-13-2010, 08:14 PM

try removing the monojet valve see if the heats any better. There is a copper screen there somehow can clog too.
usually v8 has so much heat is impossible not letting any heat thru at all.