I am currently working on a manual A/C system that utilizes bleed wires as a part of the defrost, vent and heat distribution. If missing can you still purchase them or is there an alternative repair to restore operation.
Bleed wires
- Thread starter david hill
- Start date
After I got my '70 Monaco Brougham, I was looking around near the rh of the hvac case and found this interesting looking piece of wire stuffed into the end of one of the high-silicone vacuum lines. Simply a piece of insulated, stranded copper wire that was stuffed into the vacuum line, as if to plug it. First time I'd seen that.
When I finally got a FSM for the car, I noted that the placement of the wire was termed "bleed" on the vac hose diagram for the hvac system. I left it there as sit looked like it belonged and there was nothing else in that area the vac line might have been attached to. Probably no more than an inch long?
This was on a factory a/c with heater car. Manual controls.
As an aside . . . when I got the car with about 85K miles on it, it still had the phenolic vac-operated heater water valve. I knew (at that time) they had a history of cracking and leaking, so it was replaced with one of the metal units. Little did I suspect that the larger unit apparently had a vac reservoir in it to dampen vac pulses from the intake manifold!
At certain throttle settings (i.e., intake manifold vac levels) combined with heat slide lever settings, a strong hummmming would come from the vac diaphram (i.e., variable vac bleed) in the heater control mechanism. Setting the heat a bit hotter or cooler would usually end the sound. Still, something else to find a fix around, it seems when not using factory OEM=-spec/design parts, it seems.
Just some thoughts and experiences,
CBODY67
When I finally got a FSM for the car, I noted that the placement of the wire was termed "bleed" on the vac hose diagram for the hvac system. I left it there as sit looked like it belonged and there was nothing else in that area the vac line might have been attached to. Probably no more than an inch long?
This was on a factory a/c with heater car. Manual controls.
As an aside . . . when I got the car with about 85K miles on it, it still had the phenolic vac-operated heater water valve. I knew (at that time) they had a history of cracking and leaking, so it was replaced with one of the metal units. Little did I suspect that the larger unit apparently had a vac reservoir in it to dampen vac pulses from the intake manifold!
At certain throttle settings (i.e., intake manifold vac levels) combined with heat slide lever settings, a strong hummmming would come from the vac diaphram (i.e., variable vac bleed) in the heater control mechanism. Setting the heat a bit hotter or cooler would usually end the sound. Still, something else to find a fix around, it seems when not using factory OEM=-spec/design parts, it seems.
Just some thoughts and experiences,
CBODY67
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