Need some help figuring out how to fix the heat in my sl. I have the lever type controls, no climate control. I know that the vacuum unit which controls the water valve is missing, but I have manually opened it. Problem is that I still get no heat in the car. The engine temp is fine. How can I check if the heater core is blocked? How likely is it that the "guts" of the heater unit are broken? Is this repairable by a DIY'er?

Any suggestions would help!

Thanks

__________________
Michael
________
71 MGB
76 450SL
________

United States Special Operations Command
Deployment Cell... Any Time, Any Place