Need A/C help in Florida

[76okievette]

Great post, I wish I had your problems, 55 deg air would be great! I never got my 76 down below 70. I converted to R134 and install a part called a VIR eliminator (dryer) but it never worked right, may never of had a correct charge not sure, now I have leak in the tubing right behing the compressor. I am considering just going with a system from Hot Rod Air http://www.hotrodair.com/index.cfm From Hot Rod Air

The systems require no major modifications to the car and are comprised of all new (not rebuilt) components. The kits include the evaporator, compressor, compressor bracket, precrimped hose kit with drier, condenser and safety switch. its 1200 bucks.
Has anyone ever done that or know any thing about it? It includes a total system, compresser, evaporator, consener, ducting, etc.
What do you think is it necessary to replace everything or should I just try and make the OEM system work? Thanks

 

[gmjunkie]

Great post, I wish I had your problems, 55 deg air would be great! I never got my 76 down below 70. I converted to R134 and install a part called a VIR eliminator (dryer) but it never worked right, may never of had a correct charge not sure, now I have leak in the tubing right behing the compressor. I am considering just going with a system from Hot Rod Air http://www.hotrodair.com/index.cfm From Hot Rod Air

The systems require no major modifications to the car and are comprised of all new (not rebuilt) components. The kits include the evaporator, compressor, compressor bracket, precrimped hose kit with drier, condenser and safety switch. its 1200 bucks.
Has anyone ever done that or know any thing about it? It includes a total system, compresser, evaporator, consener, ducting, etc.
What do you think is it necessary to replace everything or should I just try and make the OEM system work? Thanks

That kit is for a vehicle that has never had air!! And Yes I've put them in Antique,Classic and Street Rods!! You'll have another $1200 to $1500 in installation to make it Look like a Factory Unit in the dash!! Why bother I can make your factory AC Freeze the Balls off a Brass Monkey for $1200!! Probly Less!

Here is a couple photos of the last Street Rod I built with AC!!

 

[76okievette]

Ok, gmjunkie I will take you up on the offer, "cold enough to freeze the balls off a brass monkey" should be cold enought to keep my wife's feet cool on a 95 deg Oklahoma Aug day (the eng temp never gets above 190 so I know the eng is not running hot). I guess the best place to start is get the leaking hose replaced then see what I have.
Thanks

 

[minifridge1138]

I have no idea how old the accumulator is. I know it hasn't been replaced in the 2 years I've owned the car.

I only replaced the last compressor because of an electrical problem. My assistant got his elbow caught in the wiring harness, and when he moved his arm he ripped the connectors out of the compressor itself. Luckily, he paid for the new compressor

On a related note, what could cause the blower motor to blow poorly?
Is there a cabin air filter someplace, or something else that could be plugged with years of dirt/dust?

The area under the hood near the windshield wiper blades is clear of debris.

A previous poster (sorry, i'm too lazy to see which one) mentioned putting insulation around the evaporator. Any chance you could post a pic so we see what you did?

How big of a difference would the Ford orifice tube make? If it is a big difference, then that combined with a new accumulator and the correct amount of freon should get my air well into the 50's.

Thanks for your help. So far i've spent $1.95 for the orifice tube, and $5.00 for PVC pipe and insulation. That leaves $1,193.05 for other projects!

 

[gmjunkie]

On a related note, what could cause the blower motor to blow poorly?
Is there a cabin air filter someplace, or something else that could be plugged with years of dirt/dust?

The area under the hood near the windshield wiper blades is clear of debris.

A previous poster (sorry, i'm too lazy to see which one) mentioned putting insulation around the evaporator. Any chance you could post a pic so we see what you did?

How big of a difference would the Ford orifice tube make? If it is a big difference, then that combined with a new accumulator and the correct amount of freon should get my air well into the 50's.

Thanks for your help. So far i've spent $1.95 for the orifice tube, and $5.00 for PVC pipe and insulation. That leaves $1,193.05 for other projects!

No there is no filter in the cabin,But there have been times I've had to take part of the housing out to clean the crap out of the evaporator!! But thats not your problem, you wouldn't have had to unplug the blower motor to get the pressure drop to adjust the switch!!

The Ford Blue with a new accumulator will make a Big Difference!!Probly the coldest you will ever be able the get temp out the vents will around 53-55!! Thats Kicking azz for a factory unit!! Heck,My C5 only pushes about 56-57 out the vents on a hot day wide open!!:L:L

I think he shipped out to Iraq! And what he did will help some,Also taking out the front carpet and putting thermal mat under it clear up the front as far as you can and put the carpet back in will help some too!! There is allot of heat transfer through the front floorboards on C3's!!

But heres the kicker,you may only have to take a little out of the system now to get it to Cool right!! Like I said 134a is Not as forgiving as R12!!

"If its over 1 oz overcharged or over 1 oz undercharged the system won't work properly"!!

 

[minifridge1138]

I'm a little surprised to hear you're getting 56-57 in your C5.
My 1995 Mustang GT (Don't flame me, it was almost free) cools air to 42.

I guess those Ford orifice tubes make a big difference

Now the low side is around 22-23 and the high side is about 220. That was with 107 ambient air temp, the blower motor on 2nd click, box fan in front, and 65-68 degree air coming out of the vent.

Thank you very, very much for all of your help.

 

[gmjunkie]

I'm a little surprised to hear you're getting 56-57 in your C5.
My 1995 Mustang GT (Don't flame me, it was almost free) cools air to 42.

I guess those Ford orifice tubes make a big difference

Now the low side is around 22-23 and the high side is about 220. That was with 107 ambient air temp, the blower motor on 2nd click, box fan in front, and 65-68 degree air coming out of the vent.

Thank you very, very much for all of your help.

It may kick down at the vent little more than that!! I have Duel Zone Climate control!! Keeps the car at a constant 60 deg inside No Matter how hot the ambient temp is!!

OK Now turn it to Norm High fan and see where the Low Side and High side pressures go!! May have to dump a little more!You can remove the Box fan!! We want to try to get it at peak at idle with no cooling help!! I'll be right here!!
PS What kind of gages are you useing??

 

[minifridge1138]

I have a manifold gauge set that I bought from Harbor Freight.

Something odd happened.
I was getting 66 degree air in the drive way with the gauges hooked up.
Low side 22-23, high side ~220. Outside was 107.

Put all of the tools away. When I disconnected the high side, it hissed and shot out oil. I assumed this was just the pressure in the line.
Watched TV for a while. Drove to dinner. AC wasn't even cool. I could hear the compressor kicking on and off.
Hooked up the gauges, and the high side was 160. I added freon. Got low side to 23-24, high side to about 225. Inside vent was 64. Outside was about 89.
Disconnected gauges. High side hissed a bit (not as bad as first time). Got in the car. Inside vent is blowing 76.

How is the temp rising 10 degrees just by disconnecting the gauges? I can think of 2 things:
1) Something is wrong with my high side connector and I'm venting freon when I disconnect it.
2) The extra pressure in the lines is making a huge difference. Tools disconnected and the system looses the couple of ounces in the line.

Should the AC be the coldest at idle, or when the car is driving? I thought in motion because the compressor is spinning faster and there is air flow across the condenser.

I think i'll go to a hardware store and get a ball valve to put at the end of the high pressure side. That way I know that nothing is venting out of the lines when I disconnect the hose.

Any interest in trading that 2001 Z06 for a 1982 Carb'd corvette and a 1995 Rustang GT?

 

[gmjunkie]

I have a manifold gauge set that I bought from Harbor Freight.

Something odd happened.
I was getting 66 degree air in the drive way with the gauges hooked up.
Low side 22-23, high side ~220. Outside was 107.

Put all of the tools away. When I disconnected the high side, it hissed and shot out oil. I assumed this was just the pressure in the line.
Watched TV for a while. Drove to dinner. AC wasn't even cool. I could hear the compressor kicking on and off.
Hooked up the gauges, and the high side was 160. I added freon. Got low side to 23-24, high side to about 225. Inside vent was 64. Outside was about 89.
Disconnected gauges. High side hissed a bit (not as bad as first time). Got in the car. Inside vent is blowing 76.

How is the temp rising 10 degrees just by disconnecting the gauges? I can think of 2 things:
1) Something is wrong with my high side connector and I'm venting freon when I disconnect it.
2) The extra pressure in the lines is making a huge difference. Tools disconnected and the system looses the couple of ounces in the line.

Should the AC be the coldest at idle, or when the car is driving? I thought in motion because the compressor is spinning faster and there is air flow across the condenser.

I think i'll go to a hardware store and get a ball valve to put at the end of the high pressure side. That way I know that nothing is venting out of the lines when I disconnect the hose.

Any interest in trading that 2001 Z06 for a 1982 Carb'd corvette and a 1995 Rustang GT?

That is strange!! Unless the schrader valve in the service ports are leaking,or sticking when you take the coupler off! Schrader valves leaking is usually caused by contaminants getting in the valve!!(Like a piece of Descant from the Accumulator or a metal shaving from the inside of the compressor!!)Where was the fan speed and was it on Normal or Max!! It should defiantly cool more running down the road with higher RPM and increased air flow through the condenser!! But what we want to do is the get it as Cold as possible at Idle!!Then at higher RPM the AC clutch should cycle when the low side pressure gets down to 21 lb while your driving down the road!! It should even cycle at idle under the right conditions like lower ambient temps!!The higher the ambient temp the less it will cycle,the lower the ambient temp the more it will cycle!! Also blower fan speed and Norm or Max settings will change the cycling of the system!! Let me think on this!!I'll get back to you in the morning!!I don't think it's your gages!!

As far as trading the Z06, It would kinda depend if the deal I got cooking falls through or not!

 

[gmjunkie]

Well,After consulting my Mitchell Air Conditioning Service Manual and My FJC Guide to Retrofitting Manual I've come to conclusion,That more likely than not that the Accumulator is saturated and the desiccant bag inside is starting to come apart Internally!!

At "Low side 22-23, high side ~220. Outside was 107". you should have been getting well below 60 deg out the vents!! If the schrader valves just started leaking,that tells me that some kind of contaminant has found it's way into the valves!! The only place it can come from is the Accumulator,Compressor,Inside of Rubber Hoses Deteriorating or Gages and in my opinion it will be the Accumulator!! It's time to check the orifice tube,I suspect that you will find some Trash in it from the Accumulator!! It probly won't be as bad as the one I posted above,but there will defiantly be some in it!!:eyerole:eyerole

 

[minifridge1138]

Then I guess I know what my next project will be.

Thanks for all of your help.

I'll let you know how it turns out.

 

[Rumpity rumpity rump....]

'The orifice tube on a C3 is located in the inlet of the evaporator at the end of the high pressure line!(small line!!) Thats where liquid Refrigerant changes to gas!!134a expands at a little different rate than R12,so to be optimum the system needs a different size orifice and less refrigerant!! Go's in the long end as Liquid,comes out the small end and turns to Gas!!! Thats where the cooling comes in!! '

REPLY: Well, not exactly ; as the 100% liquid refrigerant enters the tiny orifice, it sustains a big pressure drop which in turn drops the temperature of the (still) liquid refrigerant (while a tiny portion of it immediately flashes to gas) . The overwhelming majority of the liquid refrigerant as it goes thru the orifice and enters the Evaporator, is cold liquid where it beings to evaporate as the warmer air from the cabin flows across the Evaporators tubes/fins. The liquid refrigerant contiually picks up heat from the air while it is flowing thru the Evaporator tubes ...and near the end of its travel thru the Evaporator, it finally becomes 100 % gas . It then goes into the compressor to be pumped to a high pressure / high temperature vapor which condenses into high temp/ 100% liquid in the Condensor ... where the cycle is repeated . I posted this for clarification purposes . Im a Residential/Commercial A/C Tech of 22 years . Regards.

 

[mrvette]

Hey Junkie, I check in here from time to time, and you seem to be knowing what is going on with Florida a/c problems....

I have a '72 with stock cond/evap and replacement POA and exp valves many years ago...the comp is a Sanden? from '88 vette on my SBC serp drive, and engine runs at 180=190 no problems...dual spals on the cooling....
the blower is modded to C4 specs, and the wires updated for max blower power, which is fine....the system is obviously r134 and has been for some years now...but the gauge says only 32f on the pressures, using r12 gauges....I cheat on the charging by doing my own hose adaptions....

anyway, it was recommended elsewhere that I turn the POA valve set screw about 1/2 a turn to get lower evap temps, colder air discharge....

I seem to get the best temps with only about 2 cans of 134 in there 24 oz....the discharge today is only 60f on a 100f day....and the system is sealed off into permanent recirculation as the trap doors are sealed shut and opened up/removed from the kick panel.....oh....the car is a convertible as as such gets plenty of air circulation, don't need outside air over the evap coil at any time.....

what is your approach to the dropping of the discharge air.....

OH, yes the drier canister is new some years ago....the system is not been looked at in maybe 3 years now, but has been the same way for that time span....IE, never all that great from git go....it's 'ok' but I want more....

GENE SLATER

 

[76okievette]

gmjunkie, going to order the parts for my 76, main hose set, hot water shut off, and replacement control swithches. Who do recommend that I get these from. All the major parts places have them and price is pretty even, any recommendations?

 

[gmjunkie]

gmjunkie, going to order the parts for my 76, main hose set, hot water shut off, and replacement control swithches. Who do recommend that I get these from. All the major parts places have them and price is pretty even, any recommendations?

I get all my stuff from a dealer only supply house in Charlotte,They carry Murray,Four Seasons,AC Delco,Motor Craft,FJC,Factory Air,Ready Air,ARA,Frigidaire,Harrison,and other Quality brands!!

 

[gmjunkie]

Hey Junkie, I check in here from time to time, and you seem to be knowing what is going on with Florida a/c problems....

I have a '72 with stock cond/evap and replacement POA and exp valves many years ago...the comp is a Sanden? from '88 vette on my SBC serp drive, and engine runs at 180=190 no problems...dual spals on the cooling....
the blower is modded to C4 specs, and the wires updated for max blower power, which is fine....the system is obviously r134 and has been for some years now...but the gauge says only 32f on the pressures, using r12 gauges....I cheat on the charging by doing my own hose adaptions....

anyway, it was recommended elsewhere that I turn the POA valve set screw about 1/2 a turn to get lower evap temps, colder air discharge....

I seem to get the best temps with only about 2 cans of 134 in there 24 oz....the discharge today is only 60f on a 100f day....and the system is sealed off into permanent recirculation as the trap doors are sealed shut and opened up/removed from the kick panel.....oh....the car is a convertible as as such gets plenty of air circulation, don't need outside air over the evap coil at any time.....

what is your approach to the dropping of the discharge air.....

OH, yes the drier canister is new some years ago....the system is not been looked at in maybe 3 years now, but has been the same way for that time span....IE, never all that great from git go....it's 'ok' but I want more....

GENE SLATER

I'm not to sure on what you should do.I no that 24 oz of Refrigerant sounds kinda lite to me,I know the system would be smaller with the Sanden Compressor,But I wouldn't think almost 1 1/2 lb!! Are you sure there isn't too much oil in the system??That will damn sure make them have inadequate cooling!!That original system calls for 10oz of oil with the original compressor,I wouldn't think the sanden would need more than 7-8 oz maybe less!!Conversions sometimes can be hard to figure out,I'd remove probly 2-3 oz of oil and adjust the POA from what low side reading should be with R12 and add more 134a. This will be a little hit and miss to figure out!! See attachments below for POA adjusting procedure!!

PS.Remember that your Gages can hold up to 3-6 oz in the hoses,So you have probably less than 24 oz in the system!!

 

[mrvette]

GMJ, thank you very much for that post, NOW I figger out what I think is reasons why my system does a max air out at only 60f on recirc as I described....so to now know exactly how to turn that nut/screw in the POA and get it colder...

you say too much oil is a problem....how can I tell?? how to get all the oil out and then recharge?? always a problem to figger out...guessing game, really....

then the issue of recharge, I always recharge untill no further gas seems to want to be in there, and it's usually 2-2.5 cans for the vette, as I REMEMBER....

somethng else kind of OT...on a old Dodge 3/4 ton van it keeps loosing 134 and I can't locate it....soap and detector is useless....
new evap and cond, comp is clean...so??

thanks again...

GENE

 

[minifridge1138]

My accumulator just arrived.

I have a few questions:
1) The service manual says to unmount the ac compressor. Is that necessary?
2) The orifice tube is in the high pressure line, between the accumulator and the evaporator. Correct?
3) Any tips/tricks that make this easier? It seems some of the lines going to the accumulator are hard to reach. I really don't want to break anything while i'm doing this.
4) Should I use any kind of thread sealer when I reassemble this? Teflon tape, silicone, etc.

Thanks everyone!

 

[gmjunkie]

My accumulator just arrived.

I have a few questions:
1) The service manual says to unmount the ac compressor. Is that necessary?
2) The orifice tube is in the high pressure line, between the accumulator and the evaporator. Correct?
3) Any tips/tricks that make this easier? It seems some of the lines going to the accumulator are hard to reach. I really don't want to break anything while i'm doing this.
4) Should I use any kind of thread sealer when I reassemble this? Teflon tape, silicone, etc.

Thanks everyone!

No sealers on lines just new O-Rings!!(Coat them with refrigerant oil good!)The orifice tube is in the evaporator Right where the small line go's into the evaporator!!See Photo!
Taking the compressor off will probly make things easier!!
Depending how much junk you find in the Orifice tube would determine how deep you should go!!

Here is a little wright up I've done of the correct way to properly Retro Fit a R-12 system!! Depending on how Trashy the orifice tube is,You may want to do most of these steps!! Post a good photo of the orifice tube when you get it out so I can see it!! You won't need to do all of them,but I would flush the complete system and change the oil in the system (Use Ester Oil!!)and replace the schrader valves and All O-rings!!

 

[minifridge1138]

Small snags.

1) I don't own a wrench big enough to get the inlet/outlet lines off of the accumulator. They're bigger than 1 inch, and that's all i have. (let the jokes begin). I can borrow one or go buy some. But that's not going to happen until tomorrow.
2) There is almost no room to move a wrench on the upper fitting (the one coming into the side, not the one on the bottom). I can get a wrench on it (if I had the right size) but it is wedged between the coolant reservoir and the evaporator housing. I don't think I can spin a wrench even if I get on it.

I can solve the first one, but the 2nd one has me stumped.

Any suggestions?

I did get the orifice tube replaced. Mine was black, but not covered in crud like the one in your pic. The new ford one went in a lot easier than the old one came out (just as a note, the Ford one I got (i triple checked the part # so I know it is correct) is orange, not blue (different manufacturers)).

I found something interesting in the shop manual:
"The accumulator should ONLY be replaced when:
1) a physical perforation to the accumulator is found resulting in a leak
2) the expansion (orifice) tube screen experiences continued or repeated plugging
3) The compressor inlet screen is plugged (A6 compressor)
4) An evaporator fails because of inside-out (internal) corrosion"

Part of me is tempted to go with the manual and not rip the flesh off of my knuckles trying to get a wrench in there.

Please Help!!!