Replace Heater matrix / 190E 2.6
Had a coolant leak that was creating a puddle (the size of a saucer) underneath the transmission.
After replacing the heater feed and return hoses and checking the heater control valve, I realized that the likely culprit was the heater matrix (groan!). Interestingly, there was no internal leak or odor in the car - even when blowing hot air!
Using the workshop manual, I proceeded with all the tasks that are required to remove the dashboard.
Not a particularly difficult job - but you DO need the shop manual to avoid additional frustration. I also recommend labelling ALL fastners (with masking tape and pen) and placing in containers grouped by sub-assembly to avoid confusion with re-assembly.
Label the climate control vacuum hoses too!
My heater matrix was leaking at the end-joint.
Whilst doing this job I also replaced: -
- the radiator (diagnosed as partially blocked by a local shop)
- serpentine belt (might as well, whilst radiator out)
- badly corroded transmission cooler pipe - attached to lower radiator
... a bit ambitous maybe, but hopefully worthwhile.
The radiator had been causing 'hot running' in traffic and was the likely cause of some recent hose blow-outs.
End result, no more leaks, cooler running and the heater works a treat!
1991 190E 2.6 170k
1995 E320CA 57k
1999 Chevy Tahoe 98k
2000 R1150GS 45k
1983 300CD 178k - sold, but not forgotten