On a slight tangent, it sounds like you have a lot of AC experience. What are your thoughts on an aerosol flush kit versus the type you mentioned that run on shop air?


I'd tend to favor the aerosol kit because hopefully the propellant is relatively dry, versus shop air that may be full of moisture. Or does it matter much?


Of course this may be moot, as the OP is changing pretty much everything and so doesn't need to do any flushing.

 

I've never used the aerosol flush. The shop were I worked used the canister style.


However, I never had good luck with the flushes either. The containments would build up in the evaporator and condenser, where the flush would just go around it (sure it worked a little). Its like trying to flush out a severely clogged radiator. Some say the flush does more harm than good as it just loosens up the debris and doesn't flush it all.


But if the system is clean and your just flushing the old oil out - then flushes work fine and are necessary.

So in the decade when I worked in a fleet shop we had a lot of Fords with "black death" (Google that if your not familiar with it) and we would replace the Condenser in all major AC jobs. many less come-backs that way.

 

To get a condenser with the increased heat transfer, it needs to be for a 1994 or newer, as R-134a use started in 1994.

In some parts of the country, a R-12 to R-134a conversion using the original condenser MAY work out. Not here in Texas, unless you only want to drive from 11 PM to 6 AM, or always keep your speed above 30 MPH or so, never stop or wait at a light, much less ever get caught in traffic at noon!

If I were doing it, I would replace everything. No old hoses, etc. Also need a 1994 or later CPS (Cycling Pressure Switch) which screws into the side of the accumulator/drier. I did a complete replacement on my 1994 Bronco after the original compressor seized.

A later condenser will probably have different fittings on it than your truck does, by going to a later year for everything (if it physically fits), then it all fittings connect together OK, no special hose ends needed or adapters.

 

I've been paying attention but this was my National Guard weekend warrior weekend so I haven't had a chance to respond.

I bought one of the vacuum pumps from Harbor freight when I did the AC on my car a few years ago but it crapped out on me halfway through the job and I returned it. I ended up just getting a loaner from the local auto parts store when I bought the refrigerant from them so I'll probably just do that again this time. Definitely going to get the stuff with the dye in it. I still have the glasses and the UV light from when I put it in my other car.

I ordered the condenser I posted a link to above yesterday afternoon. Hopefully it'll work down here in Louisiana. It's supposedly the one for my 86, but it's new so maybe it's been fiddled with the work better with R134a?

kr98664, can you explain the heater cut off? I read the other thread but I'm still not understanding what it is or how to do it. I did come away convinced that it's a good idea though.

CountryBumkin I'm with you on buying local, it's just in this case both of those parts much cheaper online. Locally the cheapest I could find was $80 and $124, Amazon had them for 50 and 100, and this is already way more expensive than I had originally planned.

Torky2 can you elaborate on the CPS? Good idea on replacing everything. I'm planning on taking my old hoses to the O'Riley's around the corner to have them re-make them as CountryBumkin mentioned earlier.

 

CPS=control pressure switch.
Because r12 & 134a work at different psi, the truck had r12 from the factory it would be best to swap it out for a 134a switch.

I never gave that a thought as I have seen it posted you could adjust the r12 switch?
Dave - - - -

 

Most of the pressure switches have a little flat head screw in between the terminals that you can turn to adjust the set point of the switch. You can over do this though, and the evap coil will then freeze up into a block of ice.

 

Scroll down to page 82 here for a schematic showing airflow in the ductwork of the factory AC system.

Heating, Ventilation, & Air Conditioning - ???Gary's Garagemahal

All airflow goes through the fan. Next all air passes through the evaporator, which is only cold when the AC is on. Note the cable-operated temperature blend door, just upstream of the heater core. In the original configuration, the heater core is always hot when the engine is warmed up. When full cold is selected, that temperature blend door is supposed to divert all airflow around the heater core. However, that toasty heater core is still dumping some heat into the ductwork, just by its location, even if air isn't flowing through it. Add in a little leakage around the temperature blend door, and you could end up with a fair amount of heat escaping into the cabin.

That's why a heater shutoff is a popular modification. I'm surprised Ford didn't use one on our trucks. It's a valve in the heater lines that shuts off coolant flow to the heater core. I'm running a vacuum controlled valve, teed into the existing vacuum line that controls the panel door. The panel door is what routes air to the 4 vents on the face of the dash when AC or vent is selected. So now any time vacuum opens the panel door, the heater shutoff valve also closes automatically, preventing the heater core from leaking heat into the ductwork.

 

I use a manual one like this, and they are readily available at most parts stores.

 

C5TZ-18495-A .. Manually Operated Heater Water Shut-Off Valve-Use with Economy Fresh Air Heater (Motorcraft YG-130) / Obsolete ~ Available NOS

1965/66 F100/1100; 1967 F100/750.

This valve was spliced into the inlet to heater core heater hose.

1965/72's with deluxe fresh air heater used a cable operated heater water valve (C3UZ-18495-A), that also spliced into the inlet to heater core heater hose.

 

One difference with the Ford ranger type vacuum control valve, when it shuts the heater core off it keeps the water flowing in the heater hoses, it just flows through the valve and back around to the engine. In most cases this won't matter, but if you have added a coolant filter inline with the heater hose, or like me and have added a electric fan sensor in the heater hose, then it keeps that stuff working since the water is still flowing through the hoses.

 

All the parts are in, the adventure begins! Quick question on the evaporator, I'm hoping the answer is you take it off from the outside, not that you have to take the radiator out to get to it, right? My Chilton manual doesnt have any information on changing out the AC system. I'm guessing so you'll take it to someone who knows what they're doing.

 

You can remove the fan and fan shroud then lean the radiator toward the engine. No need to drain it or pull the hoses.

 

Dave, do you have a part number or something on this valve so I can get one?


I am not thinking of adding a filter of sensor but more in line the cooling system was made to have that flow and if stopping it what that may cause with hot spots in the system?

I was going to say lean it back also as it does have to come out the motor side.
I need a condenser also but lack of $$ and needing to put the truck together will lean the radiator to install.
Dave ----

 

So far it's been a disaster. I was gonna start with the easy part, the compressor itself. The old one came out in a snap. The new one just wasn't fitting. I had to grind down part of the body to get the upper support bracket even in the ZIP Code of the bolt hole, and then I had to grind down The inside of the slot far enough to get to the threads on the whole. Maybe they sent me the wrong one, I don't know.
It doesn't look like much, but there's no way to get the bolt in without cross threading like that.
You can see where that bolt is where I had to grind down the body of the alternator behind the bolt so the upper support bracket would fit over it.

so what should've taken me 10 minutes ended it up taking me four hours. Next step is get the fan and fan shroud off and lean the radiator back. Wish me luck.

 

Did the Compressor come filled with oil? Many times it comes overfilled (enough for the whole system) so you have to drain it before installing. If this is the case, there should be a tag on it saying to drain.