I don't seem to have any vacuum to the heater valve - I assume that vacuum is required to close the water valve? I think there is a solenoid somewhere to apply vacuum? Can anyone tell me where it is and a part numer? Tks

 

There is a metal modual on heater hose next to firewall, probably rusted and not closing. Others that know more than I will chime in.

 

Vacuum to the heater valve is controlled by a switch located on the servo assembly. There are two identical switches, part # RTC1076. The inner of the two is for the heater valve


However, these don't fail often.

Do the various vacuum actuated air flow flaps operate when you change the settings? If not, you might have a vacuum supply problem--no vacuum getting to the control switches.

Do you hear a faint whirring sound if you slowing adjust the temp dial? You should. If not, the servo is not operating...and the servo actuates the vacuum switch for the heater valve.

Cheers
DD

 

I'll add that I'm assuming you have the Delanair Mk II climate control. But an "86" might have the Delanair Mk III system. The Mk III system is easily identifiable as the temp control dial has a "Pull for manual control" feature.

If you have the Mk III, post back. It's a different kettle of fish.

Cheers
DD

 

I have a Mk III unit in both my '87 and the '88 H&E I am parting out. I still haven't been able to get the unit out even though I have removed every nut or bolt I could find.

What might I be overlooking or not looking in the right place? The rest of the dash, console and facia is already removed so access is not an issue. Thanks.

PS...that V12 engine cleaned up and sitting on the heavy duty pallet with wheels I built sure looks awesome :-))

 

Brad
It probably need a good sharp shove. The insulation can stick the unit to the bulkhead.