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Zimm63

63 AC vent controls

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Working through diagnosing why my AC won't blow through the dash vents.  It used to work, but stopped last summer.  

 

All of the connections are correct (I checked).  Applying vacuum directly to #1 and #2 verifies that they operate.  After futzing around for a bit, I ran a line from the manifold directly to the outflow side of the #1 switch and things worked as they should.  That's great for now, but doesn't fix the problem, which appears to the be #1 vacuum switch.

 

Are these things available anywhere?  Is it worth while to take it out and run carb cleaner or something through it?  

 

All advice appreciated.  

 

 

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The vacuum switches are hard to find new. Look for a good used one.

 

As a temporary fix, spray a quick shot of silicon lubricant spray into the switch vacuum port and operate it a few times with your finger.  Now hook it all up and see if you don't have vacuum again.

 

This has worked for me.

 

 

 

 

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No joy with spraying it out.  Thought so for a moment when the spray came through, but then it stopped up tight.  

 

Anyone have a thought as to where to lay hands on one?  I guess I could go down the list in the Review.  

 

 

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I have a '92 Roadmaster. I don't know how close it is to a Riviera.  I found a control system from a same era Caprice worked.  The actual "switch" is chintzy!

 

  Ben

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I bought two (2) #1 vacuum switches on eBay. They are pricey for what they are, but it is a supply and demand thing. 

Adjusting the #2 vacuum switch per the 63 Service Manual directions was easy (at least for me) for center vent air flow.

Turbinator 

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Adjusting the switch presumes the switch is working, which mine is not.

 

Gene is sending me a replacement.  With any luck it will be working fine by the weekend.

 

 

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5 hours ago, Zimm63 said:

Adjusting the switch presumes the switch is working, which mine is not.

 

Gene is sending me a replacement.  With any luck it will be working fine by the weekend.

 

 

Zimm, if you are certain you have the vacuum lines routed correctly AND the vacuum actuators are working you are in free on that facet. Ask me how I know. Are you using the STV or using the STV update kit ? Reason I ask is I’m trying to find the ideal spot to wrap the  STV eliminator temp sensor tube around the suction tube coming from the evaporator. After 3 failed attempts with STV valve rebuilds I’ve gone to the STV eliminator.

Turbinator

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Mine is still STV.  for the moment, I think all that is wroing is the failed switch.  The charge may be a bit low, but that can be checked when I lay hands on an R12 machine.  

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There’s a shop in Baltimore has the reclaim machine for R12. Nice folks, but they are not mechanics. Let me know if you want the particulars. Hopefully, all you need is the switch.

Turbinator

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16 hours ago, Turbinator said:

Zimm, if you are certain you have the vacuum lines routed correctly AND the vacuum actuators are working you are in free on that facet. Ask me how I know. Are you using the STV or using the STV update kit ? Reason I ask is I’m trying to find the ideal spot to wrap the  STV eliminator temp sensor tube around the suction tube coming from the evaporator. After 3 failed attempts with STV valve rebuilds I’ve gone to the STV eliminator.

Turbinator

Bob-

Put the temp sensor on the suction line as close to the evaporator as you can.  It is designed to sense when the evaporator is getting too cold (close to freezing) and cycle the compressor off.

 

 

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13 hours ago, Jim Cannon said:

Bob-

Put the temp sensor on the suction line as close to the evaporator as you can.  It is designed to sense when the evaporator is getting too cold (close to freezing) and cycle the compressor off.

 

 

Jim, thank you. One plan is to place the sensor on top of the evaporator on the suction pipe coming from the evaporator. It’s tight it might work. If the space is not right for the sensor the sensor will go in evap box. High and dry

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Posted (edited)

OK, replacement switch did not cure the  problem.  

 

First the switch:  I can blow 6-56 through the outlet side, exiting the inlet (the direction air would flow under vacuum) but it will not activate the diaphrams.   I could not blow liquid through the old switch, so I guess I am better off- but its not operating the diaphrams.

 

Where I sit right now:  If I disconnect the inlet side of switch one and connect it to the outlet side (bypassing the switch) the diaphrams move and all air is through the dash vents.  In my thinking, this should be the same as if the switch worked properly save any vacuum loss in the switch.   I can feel, and hear, strong vacuum on the inlet side, but almost none on the outlet side.  

 

Question:  Is it possible that my original diaphrams are so stiff that the vacuum loss in the switch is enough to keep things from operating?  

 

Figure this out, and then we can talk about whether 60 degrees at the center vent with condensation is correct.  I suspect not.  

 

 

Edited by Zimm63 (see edit history)

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Got a MityVac?  Check the vacuum into the switch, out of the switch, and the vacuum needed to operate the diaphragm.

 

If the switch also lowers the vacuum, check for a leak in the input line, bad check valve in the canister, etc. That is, if the switch is designed to lower the vacuum from 15” to 5” but you’re only seeing 10” at the input, you won’t have enough at the output to operate the diaphragm.

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New Mity Vac ordered to replace my crusty old one which does not have a gauge and is missing most of the adaptors.

 

This is a solvable problem.  Just going to take some time to work through it.

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You may be able to disassemble your rotary vacuum switch and repair it. I recently bought a '67 Cadillac which has a very complex automatic climate control system. I spent a ton of time trying to get it to work correctly and what really did the trick was taking apart the rotary vacuum valve and resurfacing it to reduce leakage. I'm not sure if the '63 Riviera valve is similar to the Cadillac version but here is a link to a write-up on how to repair the valves: https://eldorado-seville.com/files/67acfix.php Scroll down a ways and you'll find the valve repair instructions. Hope this helps.

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63 Riv has three separate vacuum switches.   No rotary set up that I can see.  

 

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From my experience the #1 vacuum switch is the one that brakes more often than 2  or 3.

Turbinator.

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Trick is finding a good one.  Mine is definitely bad.  Can't get any flow through it with the Mity vac.  

 

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5 hours ago, Zimm63 said:

Trick is finding a good one.  Mine is definitely bad.  Can't get any flow through it with the Mity vac.  

 

 

Take it off the car and work on the bench.  You can gently open it up and figure out what's wrong.  Clean it up inside, look for stray bits of junk that got in there and plugged it up.  Work the plunger with your fingers and observe operation.

 

 

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Originally from the factory these vacuum switches had a very light coating of grease inside of them, which also promoted sealing.  After 30-40-50 years they dy up & pieces come off & end up blocking some of the vacuum holes.

 

 I usually use the Kendall Super Blue grease. It holds it's consistency & is not so thick it will block things up.

 

Tom T.

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Guidance as to how to open it up would be welcome.

 

It appears that the plunger end is inserted into the plastic body and retained by tiny lugs.  Can it be twisted to remove?  I need to set up my big lighted magnifying glass and have a look.  Working in a half done shop makes things harder.

 

 

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On 6/16/2019 at 7:53 AM, Zimm63 said:

Trick is finding a good one.  Mine is definitely bad.  Can't get any flow through it with the Mity vac.  

 

 

On 6/17/2019 at 10:07 AM, Zimm63 said:

Guidance as to how to open it up would be welcome.

 

It appears that the plunger end is inserted into the plastic body and retained by tiny lugs.  Can it be twisted to remove?  I need to set up my big lighted magnifying glass and have a look.  Working in a half done shop makes things harder.

 

 

Zimm, I found two (2) vacuum switches on ebay 

turbinator

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I am going to vist Gene with my little vacuum pump in hand to see if he has a good one.

 

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