My '81 380 SLC seems to have a problem with the heat. The heater blows too much heat, as if there is a valve that is stuck open or partially open. I have looked under the hood and found a cluster of heater hoses on the right-rear side of the engine compartment. There is a solenoid/valve that I assume controls the coolant flow. Is there anyway to troubleshoot this valve ? Thanks in advance for all your help.

Pay 5 bucks to George Murphy at Performance Analysis (george_murphy@compuserve.com) for his guide to troubleshooting this system.

You could need anything from a foam tube for the dash sensor to a new servo, which is the gizmo in the engine compartment.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe

Your problem could also very likely be the "mono valve" attached to the fire wall in the engine compartment. Performanceproducts4benz.com sells a
mono valve repair kit for $32.55...these can often get stuck and cause the heater to stay on. Easy to do yourself as it is a drop-in part and seal...good thing to replace anyway. Much cheaper to try this first before more expensive options...Good Luck!

JEFF & JO
84' 380SL (212K)
91' 300CE (131K)

... but the 1981 SL's don't have mono valves. They were the last of the vacuum-controlled servos.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe