AC_Heater Box Rebuild

Paul, that RANCO still looks like mine.

It looks like your stock valve is a later (?) model made in plastic. You should post up a picture with a scale so I can confirm that. I did notice that the original valve was a tad smaller than the standard 5/8 hose, but only by a small amount. Could be the diameter is 15 mm.
 
Mine is plastic

It is from an 87.

On the brass one the inlet is 0.603 and the outlet is .633. 5/8 is .625.
16mm is .629.

Also, he brass one looks just like the picture that midwest bayless sent out a ways back.




Likely it would would squeeze to fit, only if not it is a difficult place to tighten it, and if it had to come out again ...

Paul Davock
 
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Paul, Thanks.

I will check, but I am pretty sure that is the same dimension as my water valve. I have one of those somewhere that I ordered even before you did. I need to find out where it went:rolleyes:. Long story, but I have not seen it yet.

Today I wrapped up the AC_Heater box rebuild project, installed the console and filled it up with fresh antifreeze. I always leave the radiator plug loose until antifreeze starts to dribble out, then tighten that down. Dropped the rear end back on the ground after a month of sitting on jack stands. I hooked up the battery and warmed it up. The temperature needle was stuck on dead cold until it got to 160 and then promptly sprung up. The heater motor run quietly and puts out lots of air. So I took it for a spin. About a half mile down the road the heater core finally got purged of air and it started pumping out the heat. Nice clean smelling heat due to my totally spotless heater box:happy:. Before I could get back to the house I had to turn the heat down with the heater control, which is now totally smooth acting since I cleaned up the water valve and lubed the slider rod. I was practically sweating by the time I pulled into the garage. This despite the fact that it was rather cold all day today, even though it was a sunny bright blue New Mexico day. Burped some more air out of the radiator and added some more antifreeze....and called it done! One helluva project.
 
I finally tracked down the new Ranco from Israel...

and compared it with my old one. The good news is that it is almost an exact match for the 1979 heater valve with AC version. I guess the bad news is that somewhere along the line the valve changed for later models to a slightly larger diameter. However, the new right angle heater hoses I got from Obert are an exact fit. So there is no reason why a later model couldn't use this valve with the available heater hoses.
Check it out. Looks like just a substitution of the lever and trimming the mounting plate and we are good to go.
ranco_replacement copy.jpg
 
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My heater valve leak paranoia

I am glad that this valve will work. At some point I will install mine.

There is a story about why I worry so much about a bad hose seal on the heater valve.

After redoing my AC heater box I found that my carpet padding was soaked with coolant. I took the carpet and padding out, and found the coolant was leaking from the joint at the sheet metal at the bottom of the consul where it is spot welded to the floor.

I tightened all of the heater hose clamps. It still oozed slowly out. I looped the heater hose in the engine compartment. With no coolant going through the heater system I ran it again. It still oozed slowly out.

Humm. I figured there must be a pin hole in the main coolant pipes that is spraying into the upper part of the tunnel. I got stainless replacements, cut the spot welds and removed the tunnel cover, renewed and replaced everything, including the carpet. I riveted and epoxied the cover back on. When I inspected the old coolant pipes, I found that they were perfect. What?

I eventually figured it out. I was using stainless hose clamps with an inner cover for the hose, so that the gear clamp would not cut into the hose. On the clamp for the heater valve, the two parts of the inner hose cover had aligned edge to edge instead of overlapping, so when I tightened it the edges pressed together and the clamp did not tighten. The coolant had pooled in the tunnel, and was leaking slowly out in my later tests with the heater hoses disabled, which fooled me.

The 5 minute fix of loosening, wiggling and tightening the clamp turned into a six week project. The residue is that I am a bit uptight about that valve.

I learned a lot though, and had fun doing it.

Paul
 
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