Excellent taste in pets!

I think I've screwed something up taking my servo out. I marked the flap rods but i've taken the servo out a couple of times trying to repair that leaking valve. And now it seems like the servo cam isnt rotating to the correct position. Am I crazy? I read int he manual that the amplifier needs to know where the servo is but I figure it could only rotate between two set points.

Is there a calibration procedure for the servo and then flaps if I've missed something up?

 

Not sure what might be going on with your servo, is the valve still leaking ? I think I can find a good one in my pile of parts. The travel has limit switches with diodes that can prevent it from going back in the other direction if they fail, or in my case a cold solder joint. They are on a tiny board wrapped up in tape hiding in the middle of the servo harness. The servo can be tested off the car, I think it's in one of the manuals, I've slept since I troubleshooted mine while rebuilding the whole matrix because of a leaking heater core & disintegrated foam clogging up everything. I'll try to look back through my notes this week to refresh my failing memory !

Here's a link I found with the color manual and a few other files.

https://drive.google.com/drive/folde...VDcaHjBPmjcxRB

Thanks to whoever uploaded it !

Cheers,
Brian

 

This video on testing the servo may help.

Jon

 

excellent, thanks for that! I spoke to Gary at Jag-aire and he gave me some tips to set it up and I'll follow up with those in a bit.

 

That was a helpful video. Gary at Jag Aire had a slightly different reset solution.

What he recs is to disconnect the servo and then test resistance /ohms between the green and orange wire going to servo. Then, using some source for 12 volts, run the motor on the servo one way and swap leads run the other way. I disconnected the 2 wire plug to servo motor instead of trying to cram another connector into the plug.

Once you see between 0-150 ohms then you know you are at full heat. I did that and got flap rods back in the right place.

So, vacuum valve is no longer leaking, the servo gears are cleaned and greased and I have heat again---in the footwell vents.

But the side vents on dash are blowing lukewarm versus hot and so I'm back searching for solution to that. any hints?

 

Are both the center vent and the two defrost vents closed in the full heat mode? If not, you might just get a mix of air or less air flow.
EDIT: There aren't any separate control valves for the dash end vents. Make sure all of the ducts to them are completely in place. They can come loose at joints.
Jon

 

This is Exactly what I have done.

I cut this little prop, which straddles 2 fins so won't fall in, and I can take it out anytime (like now in winter when I want heat) or prop it open like this in summer when I want full AC.

It took a little trial and error (isn't that why we drive Jags?) but when I'm not using it, it takes up only little room in the center cubby.

Somewhere I posted the measurements and construction pics. I'll see if I can find them for you in you're interested.
(';')

 

Andy
If you select "defrost", automatically the entire air should be redirected to the slots below the windscreen on the dash top, and the blowers go to full speed. If this is happening the, the flaps and vents are very likely as they should be.

 

Sorry for delays in responding. I’ve got an update on this and will be back but I interrupted this project to replace water pump.

 

So, after all kinds of testing and checking, and then confusing myself with taking apart the servo and vacuum valves etc I committed the cardinal sin of problem solving/science...I changed too many things at once and have no idea what problem I originally had.

What I do know is that one of my problems was my original servo was working/moving in response to input but the camshaft lobe on the end of the main shaft was spun/spinning on the main shaft and that affected the limit switches. But because I didn't know what I was looking at, I didn't know anything other than things were moving. But Gary at Jag-Aire knew! And got my servo fixed up, along with another I sent for a spare and I also added his amplifier (my original was working but I was all in, but again, changing multiple parts at once is a no no).

Then, after installing the refurbed servo and new amplifier, it seemed to be working but something was still off. I discovered my temperature switch was not measuring the correct resistance, So I threw in a spare and now everything appear to be working with cold AC (haven't check heat yet--its summer in Atlanta GA and I can't stand the thought of MORE heat).

So, highly recommend Gary at Jag-Aire, his depth of knowledge is amazing and he is extremely helpful. People like him are rare and an asset to the restoration field.

I do have one more problem to solve with some sort of vent clanking in response to engine vacuum but I'm gonna start a new thread seeking help there.

 

Gary is one of those people who, because of his Obsession with making Classic Jaguar AC systems work correctly, seems to have made it his business to know Everything about these units, and all the individual pieces-parts involved, possible/probable faults etc., and has set out to Make It Right!

Rhetorical question: How many of us have at least One of his replacement units in our cars?
I have 3.
If he had a replacement relay box, I'd have 4.
(';')