67 LTD HVAC vac lines

[jmhigh]

Merry Christmas! I have a pristine 67 LTD, but the vacuum lines have been disconnected (or rotted away?). I get NO heat, but the heater lines are hot. Would anyone have a schematic of the vacuum line routings? Thanks for any help.

[MagicRat]

Your blender door is cable, not vacuum, so if the cable makes the blender door flap in the duct plenem, you should get some warm air coming through.

You may have a vacuum operated coolant shut-off valve installed on one of the heater hoses. This will shut off the coolant flow into the heater core until vacuum is applied to the nipple on the valve.

This valve can be removed entirely for the winter. You can test it by applying a vacuum source to it and seeing if the warm coolant flows through. Usually its hooked up to a vacuum line that runs to the heater/vent controls.

[jmhigh]

Thanks for the info. The cable and flap is working, so I'm checking the hot coolant lines.

[MagicRat]

Please let us know if you manage to fix the problem.
Good luck!

[junkyarddawg]

Originally Posted by jmhigh

Merry Christmas! I have a pristine 67 LTD, but the vacuum lines have been disconnected (or rotted away?). I get NO heat, but the heater lines are hot. Would anyone have a schematic of the vacuum line routings? Thanks for any help.

If you have factory A/C then everything is controlled by vacumn and they can be a pain as I have a 65 country squire with factory A/C,a 67 factory shop manual will have the diagrams for the vacumn lines and each has a paint dot on them to identify where the go if they are the original. The heater and A/C are two different systems and when there is a vacumn leak it goes to A/C and no heat will come out and every part needs to work or nothing. Jeff

[jmhigh]

Jeff, sorry for the delay in responding. I've been away. Yep, I've got a messed up HVAC system. I have repaired a couple of vac leaks, but some of the hoses are missing or pulled loose. I fixed the vac pull so it's not blowing cold air out the AC vents, but still no heat. I don't know how the vac lines are to be connected from the inside control to the vac ports on the firewall. (390 V8 and factory AC). I really need a schematic showing how the various vac lines are routed. Any help would be much appreciated. Thanks.

[junkyarddawg]

Send me your address and I can draw you a schematic on where they go,for the time being bypass the heater controll valve near the battery and you should have heat but you will not be able to controll the temp by the controlls. Jeff

[jmhigh]

E-mailed to you this a.m. Thanks for your help, Jeff.