My 66 has the infamous Comfortron, from the few times I've run the car so far it appears that the heat is working but the fan seems to work when it wants to. Sometimes no fan at all, other times just get the high speed. When it's no-fan I don't hear anything moving when switching from heat to defrost etc., pretty much the whole thing off. Could this be an issue with he servo motor thing under the hood?

 

It could, or it could be the vacuum transducer under the dash. It could also be the main vacuum switch on the firewall. While running the car (motor up to temperature) set the lever to the "high" position. Adjust the temp wheel to the highest and lowest temp leaving it at the extremes long enough to see if the arm attached to the back of the vacuum modulator on the firewall moves back and forth. This arm should move to different positions on its own while you change the temp dial setting, or change the dash lever from "high" to "defrost". If the arm on the vacuum modulator moves, the problem is electrical (in modulator or elsewhere). If the lever does not move, it is most likely in the vacuum system. I say most likely, because it could still be electrical, but probably not in the electronics of the firewall modulator.

 

I'm not a Comfortron guru by any stretch...but check the ground connection at the blower motor and the power wire (purple?) to the motor.

They are probably ok as high speed works; but, the higher voltage on high speed might be enough to make the connection.​​​​​​ Check for voltage to the motor when it won't work to rule out a possible worn blower motor.

What model Toro 98 ?

Good luck!!!

 

It's a 66 Toro thx

 

Loaded68,

Is the vac modulator you mentioned under the hood or under the dash? I'm assuming the lever i'm looking for to move is the one near the top of the cowl by the wipers?

 

Also, if the car is not running should I still be able to turn the fan on and off with just the key turned on?

 

Yes, the vacuum modulator is under the hood. The moving lever comes out the back of it and moves back and forth to change the air temp coming out of the vents. The vacuum hoses on the rubber plug mounted to the top change which vents the air is blowing out of.

 

The comfortron system needs vacuum to turn the system on. The picture below is the master vacuum switch located under the hood. It will turn on with engine vacuum if the engine is up to temp (I think over 120 degrees) (heat in winter), or the interior is over 70 degrees (AC in summer). My 68 has a De-Ice setting past defrost that forces the blower on regardless of engine temp or interior temp. I don't think 66 had this feature so it may only turn the system on with proper engine or interior temp. If the engine is up to temp (shut off after running) and there is enough stored vacuum in the system, it may turn on with the engine not running. I know that my car looses stored vacuum fairly quickly without the engine running.

 

Here is a pic of the vacuum modulator and master vacuum switch on my 68.

 

Loaded...that is a great looking engine bay!
UHV capacitive discharge ignition too?

 

What's that big silver thing in front of the servo unit? Mine doesn't have that

 

Loaded, is that switch located on a silver bracket in your pic?

 

Cruise Control motor.

Suggest reading thru the Comfortron section of your 1966 shop book to get a good handle on how it works. There's also a Comfortron training supplement manual and a Comfortron tester.

Keep in mind a Comfortron has to have vacuum to operate and does not start until coolant temp is about 120°. It has a servo that, with the system in one of the AUTO modes, starts the blower on a high speed and then as the car interior reaches setpoint temperature the servo will reduce or increase blower speed as needed to maintain that setpoint.

It's a marvelous piece of engineering, just a little prone to its sensitive components failing. Saving grace is Olds components seem to be more available than Buick, Chevy or Pontiac.

 

Thanks,
Yes the car has UHV along with almost everything else available in 68. When I got the car in 2018 it had been in storage since 1986 (obviously a damp garage from the condition) and one family owned since new. I ripped it completely apart and rebuilt everything. The car was ordered new with over $2400 of options on top of the $4700 base price. I believe the only thing it was not originally ordered with was bucket seats and a console. It has a 6-way power strato bench with headrests and a reclining passenger seat back.

To the OP, yes, the master vacuum switch on my car is located on the heater box just behind the distributor.

 

Rocket raider, does that mean that the fan will not work at all until the car is warmed up? Meaning no defrost, etc?

 

Setting it to DE-ICE bypasses all that. Even with no hot water available the a/c compressor will dehumidify enough air to clear fog from the windshield.

You're aware the a/c compressor runs full time except in OFF or VENT, right?

 

I am aware of that except mine has no Vent setting.
My fan doesn't come on in any setting, except a couple of times when it suddenly worked in the Hi setting, seems to be somewhat random.

 

The compressor is unplugged right now, would that affect the auto climate control at all?

 

Fiddled around a bit since we had nice weather, seems like every time I shut the car off for a few minutes, when restarted the hi fan comes on for a minute or 2, then shuts off. Seems to randomly go to defrost, lower or dash vents.
Also, whenever the fan comes on it blows outside temp air, but when the fan shuts off I start getting heat from the floor.

 

According to the service manual if it's on Deice it bypasses the whole auto thing, so it should work on De Ice no matter what?

 

Sort of: The system still needs vacuum to turn on, even under "de-ice". The de-ice setting simply bypasses the thermal vacuum switches on the engine and in the dash so that the system will run without the engine being up to temp. Vacuum is still needed to get the system running.

 

So if that works intermittently as well it might be a vacuum issue?

 

Vacuum is certainly a good place to start looking.

 

There was this guy...

Greg "Dr. K" Kennedy was/is a Comfortron expert. He lived a couple hundred miles from me, but has since moved. I just sent him an e-mail, we haven't talked since forever.

http://www.toronado.org/forum/viewtopic.php?t=1241

The link above includes links to a Comfortron service brochure.

 

Just curious what would happen if I were to bypass the servo or transducer by “shorting” the vacuum lines together, thus having continuous vacuum?

 

I don't know if this helps but I replaced my COMFORTRON Heater Valve on my 70 98 and the blower started working again. The little vacuum switch on the heater valve was plugged and was blocking the vacuum line to the master vacuum switch. Until then I had bypassed it with a direct electrical switch to turn the blower on and off. Once it worked I pull that switch but I still only have defrost, de-ice, and lots of heat. My center vents still don't work but as long as defrost and heat work I can always open the windows.

 

I think it will go to full defrost, but I would have to look into it more. However, you will also need to supply vacuum to the main power switch. If you are trying to make the system manual, it might make more sense to use an after market choke cable to adjust the vacuum motor to the desired setting and supply vacuum to the main power switch.

 

Some of the vacuum lines in that area (I would have to look up which ones) have plugs in them to reduce the vacuum. They are not actually plugged shut, they have a small hole in the center.

 

It was the valve, the restrictor is still in the vacuum line for it. I actually picked what looked like dirt out of the vacuum port.

 

 

You would need to cut up the servo motor (buy one just to cut up preferably so you don't destroy the only one you have). When the system is working properly, the position of the servo plunger controls most of what is going on in the system. As I said, you would need to run a vacuum line directly to the master switch to give the system power, but after that a pull cable controlling the position of the plunger in the servo will control blower vents, blower speed, and temp. The switches in the dash control would still work to control high vs. low speed settings.

Personally, I would just fix the system, but if you are set on bypassing it, I think a manual cable may be your best option. The most likely problem areas in these systems beyond vacuum leaks are the vacuum transducer under the dash mounted on the passenger side firewall and the circuit board on the underside of the dash controls.

 

Also, as long as the inside and outside temp vacuum switches work (heater valve and dash control) you would not need to change the vacuum routing to the master switch.

 

Wow look at that the inside of that thing! What about converting to a manual system? Sounds easier than getting this one to work

 

If you can find ALL of the parts and don't mind pulling off the passenger side fender or pulling the engine and trans that would be an option.
When I did my car, I left the fenders/ inner fenders on but I took everything else under the hood, under the car, and in the interior out. I believe you could swap the firewall blower box without pulling the motor, but you may need to pull the pass fender. It would depend whether you can replace only the firewall box containing the heater core, or if you need to replace the heater core box along with both halves of the evaporator box.





The shots below all show the car going back together.

 

Just curious why you have to change the heater box etc to convert to standard non-Comfortron?

 

The 66 and 68 systems are a little different when comparing comfortron to standard systems but in either car, the heater box (at least the portion that houses the heater core) on standard A/C cars does not use the servo to control the hot/ cold air door and the provision to mount the comfortron servo is not there. On the comfortron cars, the servo area is cut out and the servo controls the hot/ cold air door.

Standard 66:







Comfortron 66:

 

Oh wow didn’t realize that. Nothing is easy with these cars is it?

 

You can certainly say that again. I have worked on a lot of cars over the last 20 or so years, and my Toro is by far the most complicated car I have ever restored. Those who complain about how hard it is to restore a cutlass (compared to a camaro or chevelle) don't know how easy they have it.

 

Hey just curious what’s that black cylinder thingy on the front of the intake under the upper hose? Mine doesn’t have that

 

Distributor thermal vacuum switch for 1966 California emissions plumbing. It does the same thing as later intake mounted DTVS.