So let's talk about dealer A/C for a moment

Gary Lewis wrote

Hi-Lo Vent: Also called Deluxe Heat, this had vents/registers in the dash just like the Integral A/C system.

Well that's interesting. I didn't know such an option existed. When they had the dash vents/registers, then I just assumed that meant they had AC.

ArdWrknTrk wrote

FuzzFace2 wrote

On some of the smaller fan units we went with Gilmer belt drive setups and var-i-speed controllers.
The Gilmer belts (think blower belt) do not slip like a V belt does so all the energy going to the motor was sent to the fan wheel. At times you could cut back the speed of the motor or turn it off to save energy.
Dave ----

<pedant mode>If belts are slipping you either have them adjusted wrong or the wrong one spec'd.

All power transmission systems lose energy.  It's a fact of thermodynamics.

First, no motor is 100% efficient.  746W in, does not make 1hp out.

There's also friction from the bearings supporting each sheave (or sprocket), and just flexing the rubber as it passes around each pulley creates heat in the belt.
That energy (lost as heat) has to come from somewhere.
And that 'somewhere' is the kinetic energy imparted by the motor.</pedant>

Just like the brakes in your truck don't 'create' heat.
Friction changes inertia into heat, shedding momentum energy from the system and slowing the truck.

Going with a Gilmer type belt you are using more of the energy the motor is putting out.
A V belt no matter how tight you get it will have slippage and the tighter you get it the more wear on bearings you will have.
The Gilmer belt you don't have to go as tight so less strain on bearings, you don't have heat build up from V belt slippage, this slippage also causes the shives to wear and need replacing over time.
This set up was used on 10 - 30 HP motors and would replace 3 V belts with 1 Gilmer belt.

We found after the belt change the motors were over ampping with the fans putting out the same RPM/CFM and had to make changes to get the amps down but same CFM output just don't remember what that was 25+ years later.
Dave ----

I think we're in complete agreement here Dave!  

FuzzFace2 wrote

Going with a Gilmer type belt you are using more of the energy the motor is putting out.
A V belt no matter how tight you get it will have slippage and the tighter you get it the more wear on bearings you will have.
The Gilmer belt you don't have to go as tight so less strain on bearings, you don't have heat build up from V belt slippage, this slippage also causes the shives to wear and need replacing over time.
This set up was used on 10 - 30 HP motors and would replace 3 V belts with 1 Gilmer belt.

We found after the belt change the motors were over ampping with the fans putting out the same RPM/CFM and had to make changes to get the amps down but same CFM output just don't remember what that was 25+ years later.
Dave ----

ArdWrknTrk wrote

<pedant mode>If belts are slipping you either have them adjusted wrong or the wrong one spec'd

All power transmission systems lose energy.  It's a fact of thermodynamics

There's also friction from the bearings supporting each sheave (or sprocket)</pedant>

Im not trying to 'school' anyone here.  
Just getting the facts straight.

As you've seen, slippage is a feature, not a bug.

It lessens starting torque loads on a motor, reducing inrush current needed to get an electric motor up to operating speed.
A soft start controller is another solution. (Like the LRC regulator for the 3G)
It is also limiting torque applied at the top end, keeping the motor from overloading.
Again, that is a design choice (spec) not inherent in all V-belt drives

This is very evident when you're paying the electric bill for 7,500 watts, or 22,500 watts, 24/7/365.

First law of thermodynamics: Energy is always conserved, neither created or destroyed.  

A motor takes electron force and converts it into kinetic energy.
The Gilmer belt is thinner (less beam), and lighter for the transmission rating, so it has less inertia, less flexural heating, and subjects the bearings to less radial load when properly tensioned)
 
More is not 'all' (again thermodynamics), but all the energy the motor is putting out is getting used
It may not go to your purposes.... but it is getting 'used'

Look at why we have 'toothed' V-belts. It isn't always so they can fit a smaller sheave.
Sometimes it is so less energy is 'wasted' (as heat) in flexing them.

Question about you guys with dealer installed AC systems...

Was the passenger side factory NON-AC dash cut to accept the passenger side vents? Is that what they did? Just cut holes in the dash and push the vents in, and connect flexible ducts to them?

Yes, minus the ‘flexible ducts’ bit.  On mine the plenum is immediately behind the vents, so they open right into it with no ducting required.

Can you tell me the outside dimensions of the passenger side vents?

Rembrant wrote

Can you tell me the outside dimensions of the passenger side vents?

So you can size the hole?  Or do you want the outer dimensions of the face as well?

Or I can stop asking questions and start measuring things:

The horizontal width of the body is 1.875":



The vertical height of the body is 1.625":



The depth of the body (I'm not sure what use this would be aside from completeness) is a hair under 1.25":



The face is an additional 3/32" on each of the four sides, so an extra 3/16" on overall height and width.

That's great Dorsai, thanks!

I'm just playing around when I have free time on piecing together the parts needed to install an aftermarket AC system. It may never even happen, but I'll at least have a file on what parts I need to make it work. There are some aftermarket vents available, so I'm just seeing what I can find that will fit reasonably well and if they look close to a dealer system I'm OK with that.

I know I am a bit late to the party here, but I will add this.
My truck came with dealer installed a/c, and used the dual belts around the alt, a/c, and water pump. This system would eat belts up in just a couple years of regular a/c usage, and if the a/c was not used much the belts would last MUCH longer.
I figure it was due to the York compressor pulley having wider grooves than the other 3 pulleys. The belts simply rode too deep in that a/c pulley, and when it was seeing regular use the extra friction would wear the belts enough that they simply lost grip in the a/c pulley.

BTW, finding a matched pair of v-belts is getting much harder to do as the years go by..

Gentlemen,

Just to put a bug in your ear, I'm looking for a set of the passenger side dash vents from a dealer installed AC system if you happen to come across any.

???

https://www.ebay.com/itm/Heater-Box-Plenum-A-C-vents-control-ASY-1980-96-Ford-Truck-Bronco-F150-F250-F350/163281615100?hash=item260457b8fc:g:7QkAAOSwLmBb3AwR

https://www.ebay.com/itm/FORD-80-91-F150-F250-with-dealer-instaled-air-conditioner-AC-outlet-ORIG-NOS/254215262837?hash=item3b30691275:g:IsMAAOSwpw1ahzt7