Does anyone know the correct vacuum source for the vacuum operated heater valve mounted at the front of the intake manifold of a '54 Mercury? Thanks, Alan S. Freeman

I'm a little confused by the question. I believe the manifold is the vacuum source and a vac line goes from the small fitting on top of the valve thru the cowl to the heater control valve under the dash on the passenger side.

Marc

'54 Merc ragtop

Pt Townsend, WA   

                                                                                                                                   

I am trying to hook up my wiper motor, vacuum windshield washer and heater and I am just "winging it" ( i.e. guessing) as to where all of these many vacuum lines go. I haven't been able to find any kind of diagram of the vacuum lines for the wipers/washer/heater so any help would be appreciated. Thanks, Alan

Alan, I seem to remember that the vacuum to the heater water valve on the manifold is routed from the 'temperature control valve' located under the dash by the heater. The temperature control valve is controlled by a cable from the heater control panel. As you adjust for more or less heat it allows the heater water valve to open or close. Maybe follow this cable to locate it.

Vacuum to the 'temperature control valve' is routed from the intake manifold and possibly the fuel pump if you have a dual action pump. This same vacuum line supplies the wipers.

Please confirm this as it has been a long time since I messed with the vacuum lines and my memory is fading as fast as my eye site. Hope this helps even just a little.

"The Master Cylinder"

Enjoying life at the beach in SOCAL

Without crawling under my dash to check, this is how I think I set the vacuum up. Vacuum comes from the vacuum assist fuel pump or from a fitting on the intake manifold. A hose carries it through the firewall where it tees. One leg goes to the wiper control knob, and the other goes to the valve on the heater that is controlled by the dash lever. From the valve, it goes through the firewall and to the vacuum valve on the front of the intake manifold that opens and closes to allow hot water to flow to the heater. Hope this helps!

When Injustice Becomes Law, Resistance Becomes Duty

I think the vacuum source for the heater is in a "T" off the line to the wipers.

Budman and Genuinerod got it right. The source of the vacuum is either the intake or the fuel pump. The line goes into the inside and tees off to the wipers and to the control valve at the heater. It comes out of the heater control valve to the valve on the intake. The route back to the outside usually follows the heater hoses. At least that is how the Fords are, assume Mercs are the same.

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Thanks everyone for your responses. It just seemed strange to me that this many devices (i.e. wiper motor, windshield washers, valve on intake and valve on heater) would all be working off of one small vacuum line from the fuel pump vacuum booster. Thanks again, Alan

Just to be clear, the main source is engine vacuum via the intake manifold and the fuel pump is meant to supplement under low vacuum situations, i.e. wide open throttle such as when going uphill.

"The Master Cylinder"

Enjoying life at the beach in SOCAL

My 56 has a vacuum tank attached to the lh inner fender, not hooked up to anything. Wipers are now electric, washers are disconnected (no bag), no power brakes.

Looks original?

Will post a pic when site is repaired.

Al.

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South Australia