Coolant leak

[ajwolf]

Good morning everybody. I'm trying to find out more information about this part, that is now leaking rad coolant when I fire up the car. It has two holes in the body which I assume are weeping holes to let you know there's a problem with it. I'm sure there's a diaphragm inside that is no longer functioning properly. Would anybody know what this part is called and where I could find a replacement, as the edges are crimped and really not on the serviceable side of things. I will supply two pictures to indicate what I am looking for.

[Milsteads Garage]

Those are your heater control valves and if they are leaking they are defective. They are very hard to find if Mark II enterprises doesn’t have them.

[ajwolf]

Thank you Morgan. I feel really lost sometimes with this car. I cant find information on things like this anywhere.
I hsd a 55 Chevy for 33 years and the info on them was everywhere .
You could get pictures, shop manuals, repair manuals, and more. This car has such poor repair information available.

[Barry Wolk]

Do you own a Service Manual? It’s very complete.

[Egenolf]

If you can?t find new vacuum heater control valves, you can substitute these ones with manually operated valves.

I did this in car 1966.

https://www.markiiforum.com/showthread.php?7339-1966-Repairs-and-recommissioning/page12

The valves are operated via the original lever and cables.

[ajwolf]

These are the books that I have and none of them are service manuals per say.

[Barry Wolk]

I'd advise you to get one.

Be advised that Elmer Rohn discovered something about fluid dynamics that they missed in engineering the Mark II. Water, oil, and electricity follow the path of least resistance. They found that an imbalance in flow flow rates prevented the heater core with the lower flow rate to get little or no water to that coil. It's a simple test. Hook the valves to a water source, like a garden hose, and a vacuum source, like your Mark II, to let the valve fill a 5 gallon bucket while timing the fill. If the valves are more than 10% different you might have flow problem.

[ajwolf]

Thank you Barry. I do have a follow up question. Is there a true service manual other then the ones i have?
I found no mention or picture of the 2 heater control valves. After you mentioned if I had a good service manual I'm wondering if I don't have the one that you are talking about. Please advise. Thank you

[Barry Wolk]

Mine is a reprint.

33150

[Roger Zimmermann]

I have an original shop manual if you don't find one locally, but the "technical data" you have is the sole shop manual . I used it while I was building my 1:12 scale model. I have to confess that the heater system is not included...

[Barry Wolk]

Chapter 11 covers the cooling system.

[ajwolf]

Exactly. There are a lot of subjects not covered in this manual. The vacuum antenna, the vacuum system itself, the headlight assemblies,
Just to mention a few. Thank you for your reply though.