A/C issues.. Are these normal?

[-=Jeff=-]

So my A/c sort of works.. but i want it to work better (if that is possible)

Last year when I went on a 3 day trip with the car it had a hard time keeping the interior cool when the sun was out, if the sun was behind a cloud the AC worked better. Then I thought it was low on charge (it is converted to r134a)

This year I have the same issue, but not only with temperature but Volume of air coming out the vents. I replaced the blower motor with one I had. the blower motor I installed seemed to spin better then the old, but the volume is still not there

When I had the Blower out i looked to see if the Evaporator was plugged with junk, but looking through the motor hole, the Evap looked okay

Where do I need to look now? I know on a 90 deg day currently i get about a 30 deg drop out the vents so my A/C charge could be low, or maybe my Compressor just is not working as it should. (need to throw gauges on it again)

about 2 years ago with the AC on, the compressor did make and odd noise, I shut it off and then tried it a few weeks later and it seemed fine then and no issues since.

Since I have had to replace most of the accessories off the belt, maybe the compressor is bad and it is not cooling the ac as much. since on a High blower the ac air seems cooler then on a lower blower setting, while my Daily ride the air is cooler if the blower is slower...

Dunno, looking for suggestions and ideas of what to check next

[Aurora40]

FWIW, mine is fairly unimpressive in operation too. The air is cool, but the volume of air doesn't quite cut it. It definitely works better when the car is moving though.

I had mine discharged, the expansion tube changed, purged, and refilled (R-12) about two years ago to make sure the charge level was right.

If the car is always garaged when stopped, it seems to be adequate to keep the car cool. But if the car is baking in the sun, the A/C never really gets it cool again.

I sort of think that's just how the A/C is.

[-=Jeff=-]

thanks bob,

how is the temp out of the vents on the lower speed settings? mine seem like th only way I get cool air is on High fan (C60 so only 4 speeds) my 89 had better AC cooling ( out the vents)

[GOLDCYLON]

Mine comes out in the 55 degree region. I was having problems with air volume but I resolved that with a new blower motor a few years ago. I remember reading that the reason that we have that nifty front solar loaded glass was because GM undersized our AC compressors due to fitment issues with the LT5. So the engineering compromise was the Sun loaded front windshield. So if your not running with a factory windshield..... That will heat things up a little.

My Friend Phil was complaining about his volume of air recently in his 91. I think these above issues are a part of the problem or AC woes for all our cars. I know the Ac controller above the gas pedal can be a problem as well but the biggest problem with those controler have been to a soft vs. hard nipple collaspse in the 96 C4 platform only. This would cause an alternating flow between both the defroster and the normal vents.

My last thing to say Jeff is you mentioned you converted the car to 134A. I have done this to a few cars over the years and both times I have been completely unimpressed by the cooling abilities of both vehicles. I would have used the artic freeze stuff or maybe a few cans of R12 from Mexico and not recommend converting over to 134. I realize you live in IL Jeff do I can understand not taking a run to Mexico (LOL)

Bob made a few good comments as well. The AC performs well when the car is moving, check underneath the car to see if the evap fins are bent or clogged as well. Just some comments and Ideas. GC

[GOLDCYLON]

And you guys in AZ are fighting illegal immigration when they are bringing you R12 ;)

Who said they are bring it in lol

[-=Jeff=-]

Yeah R134a is not the best and the cool is not that of r12. but it is easier to get... LOL

I do have a regular replacement windshield which I know does not help.


for cooling I think I am going to buy a Parallel flow condenser to replace the tube and fin that is stock

[rhipsher]

I'm still running R12 but the A/C always sucked on these cars from everything I've heard. Youd think with as small of a cabin space we have that it shouldn't take that much to cool off. Another problem is that the transmission creates allot of heat that radiates up through the shifter boot. If I set my cell phone in one of the cup holders my cell phone gets really warm. So the A/C has that working against it to. More insulation would help in that area.

[John Boothby]

Are you using the Auto mode? There is also a HIGH mode, you may want to check that to see if the volumn increases. My A/C works fine out here in Nevada. My problem is the engine starts to overheat in city traffic with the a/c on.

[-=Jeff=-]

Are you using the Auto mode? There is also a HIGH mode, you may want to check that to see if the volumn increases. My A/C works fine out here in Nevada. My problem is the engine starts to overheat in city traffic with the a/c on.

I have no auto mode.. I have C60 not C68.

I ordered a parallel flow condenser. After talking to a refrigerator guy at work ( as well as a car guy) he thinks the Compressor should be fine/ big enough, but the condenser might not be efficient enough, especially with r134a. He suggested I find a parallel flow Condenser to try which would improve cooling. I found one and bought it. once I get it I will post details, it is suppose to be a direct fit to our cars. I noticed that the 97-present corvettes also use a parallel condenser over the older tube & fin like we have.

maybe that is all I need.. (hope so)

[pantera1683]

I have no auto mode.. I have C60 not C68.

I ordered a parallel flow condenser. After talking to a refrigerator guy at work ( as well as a car guy) he thinks the Compressor should be fine/ big enough, but the condenser might not be efficient enough, especially with r134a. He suggested I find a parallel flow Condenser to try which would improve cooling. I found one and bought it. once I get it I will post details, it is suppose to be a direct fit to our cars. I noticed that the 97-present corvettes also use a parallel condenser over the older tube & fin like we have.

maybe that is all I need.. (hope so)


keep us updated

[-=Jeff=-]

keep us updated
:thumbsup:

[John Boothby]

Oops! Sorry, I forgot that you had one of the rare manual a/c's.

[-=Jeff=-]

Oops! Sorry, I forgot that you had one of the rare manual a/c's.

No worries John

I think the R134a and the Regular windshield are going against me.

I need to get he stuff Craig used in his tunnel to help too, since I will be pulling the trans this winter..

I just hope it is a direct fit like the website claims

[GOLDCYLON]

Another problem is that the transmission creates allot of heat that radiates up through the shifter boot. If I set my cell phone in one of the cup holders my cell phone gets really warm.

Replace the rubber shift boot under the leather cover and that problem will go away

[-=Jeff=-]

Replace the rubber shift boot under the leather cover and that problem will go away

I agree, amazing difference

[pantera1683]

Jeff,

Any updates on the parallel flow condenser?

[-=Jeff=-]

Jeff,

Any updates on the parallel flow condenser?


I am sorry to say.. No, I have not had a chance to do anything.

However, the condenser is correct for our cars and is a parallel flow.

Talking to a couple refrigeration guys at work, the parallel flow condenser will help efficiency, but I decided to wait until I got a new compressor as well and do it all at once. I think my Compressor is partially working. Plus I have a 2nd grader so I volunteer for his cub scouts (Asst. Den leader) and help with his Soccer team too..

I will get to it though

[pantera1683]

What are the details on the condenser? Do you have a brand and part number?

[-=Jeff=-]

http://www.autopartswarehouse.com/sku/Chevrolet/Corvette/ACI/A-fs-C_Condenser/1990/ZR-1/8_Cyl_5-dot-7L/P32603P.html?tlc=Engine+%26+Drivetrain

is where I bought it from

[USAFPILOT]

sounds like my a/c I am very interested in this...

[carter200]

Jeff,
Use the arctic cool (tall blue can) and you'll notice a huge difference. I had the same problem of poor cooling in my Navigator and did the Arctic cool treatment and now it'll freeze your wavoo's off. Takes a minute or so to cool the Gator but that is alot of space compared to our Z's. :-D

[-=Jeff=-]

Jeff,
Use the arctic cool (tall blue can) and you'll notice a huge difference. I had the same problem of poor cooling in my Navigator and did the Arctic cool treatment and now it'll freeze your wavoo's off. Takes a minute or so to cool the Gator but that is alot of space compared to our Z's. :-D

Thanks for the tip Carter..

I will try that as well, since the Alt, and Water pump went in the last year, i figure I may as well replace the AC compressor while the system is open..

Also it have been in the 70s here so hard to test out the AC anyway

[Ccmano]

I changed mine over to R134a as well. It cools very well with outlet temps down to the 38-42 deg range depending on the ambient temperature. The problem is the volume of air. It just doesn't put out that much even in recirculate mode with the fan speed on 10. I recently pulled the side cover on the evaporator housing to check for dirt. I didn't find a ton, but there was a moderate amount of stuff blocking the evaporator. I cleaned it with a vacuum cleaner and a brush and removed the multi-layer screen on the outlet side of the evaporator. It helped, I probably got a 20% increase in air flow. It now just barely keeps up on a hot (90+ deg) Southern California day. As has been pointed out it's a marginal system to begin with.

Jeff, with the dusty conditions your car lived in, have you checked for a blocked evaporator?
H

[Z51JEFF]

And you guys in AZ are fighting illegal immigration when they are bringing you R12 ;)

Several years ago I took a CFC Certification course and the instructor told the class that illegal smuggling of R12 surpassed heroin smuggling.

[TFENT]

Jeff,
Use the arctic cool (tall blue can) and you'll notice a huge difference. I had the same problem of poor cooling in my Navigator and did the Arctic cool treatment and now it'll freeze your wavoo's off. Takes a minute or so to cool the Gator but that is alot of space compared to our Z's. :-D

Carter200:

Is this the stuff you are referring to?? ARCTIC FREEZE 22-OZ. R-134A REFRIGERANT

[carter200]

Carter200:

Is this the stuff you are referring to?? ARCTIC FREEZE 22-OZ. R-134A REFRIGERANT

I'm more a visual guy but probably so. It is sold at Walmart so check there to verify. Only tall blue can the has Arctic in name. Good luck...

[Don in VT]

Hi,

I just dropped in on this thread because I too have concern with the poor performance of the ZR1 A/C systems. This may or may not apply here but I will pass it on FWIW.

My 87 L98 Vette was converted over from R 12 to 134a 3 years ago when it was obvious that R 12 was not the way to go because of the controversy over R 12 and the ozone layer depletion. ( I firmly believe that the Ozone layer thing was a hoax anyway):fahne:.

I have the electronic climate air option on the 87 and it works GREAT with the 134a so I am happy on that account but I had a very low flow from the vents and intermittent blower operation. Changed the speed controller, didnt help. Finally the blower motor failed. I tried to find a replacement and was not happy with the options available to me up here in northern VT. I went to my local salvage yard and poked around until I found a blower motor out of a early 90's Chev Suburban (full size) It appeared that the blower motor was the same size and had everything in the right place so I put it in the 87 and it worked great. Compared to the original blower it was unbelievable as to the amount of air it circulated. It blew so much air that I had to keep it turned down to be comfortable.

My thought is that the Suburban blower motor is designed for a much bigger volume and could be capable of more air flow. Anyway it really works great.

BTW, the part number for the Vette OEM is not the same as the Suburban. It is also not considered a replacement in the Vette.

It might be worth checking this out as it really saved the day (and the summer) for us.


Again, FWIW

Cheers

Don in VT

[-=Jeff=-]

Hi,

I just dropped in on this thread because I too have concern with the poor performance of the ZR1 A/C systems. This may or may not apply here but I will pass it on FWIW.

My 87 L98 Vette was converted over from R 12 to 134a 3 years ago when it was obvious that R 12 was not the way to go because of the controversy over R 12 and the ozone layer depletion. ( I firmly believe that the Ozone layer thing was a hoax anyway):fahne:.

I have the electronic climate air option on the 87 and it works GREAT with the 134a so I am happy on that account but I had a very low flow from the vents and intermittent blower operation. Changed the speed controller, didnt help. Finally the blower motor failed. I tried to find a replacement and was not happy with the options available to me up here in northern VT. I went to my local salvage yard and poked around until I found a blower motor out of a early 90's Chev Suburban (full size) It appeared that the blower motor was the same size and had everything in the right place so I put it in the 87 and it worked great. Compared to the original blower it was unbelievable as to the amount of air it circulated. It blew so much air that I had to keep it turned down to be comfortable.

My thought is that the Suburban blower motor is designed for a much bigger volume and could be capable of more air flow. Anyway it really works great.

BTW, the part number for the Vette OEM is not the same as the Suburban. It is also not considered a replacement in the Vette.

It might be worth checking this out as it really saved the day (and the summer) for us.


Again, FWIW

Cheers

Don in VT

Very interesting Find Don.. I swapped to the spare OEM blower I have, but might check out the suburban one

thanks

[-=Jeff=-]

the 90s suburbans (up through 1997) use a 1 wire Blower motor..

was it front or rear AC blower?

any more info would be GREAT

[lakemeadzmonster]

What I have found is the amount of heat coming through the firewall and console area is excessive, somebody was telling of a product that you put under your carpet and console and it makes a huge difference in heat and road noise entering the vehicle, I had a quote for $450.00 installed. I would have to call to get the name of the product.

[pantera1683]

Yeah, I'm interesed in the blower info too. It seems like it would be a good mod to prepare for next summer.

[TFENT]

Yeah, I'm interesed in the blower info too. It seems like it would be a good mod to prepare for next summer.

Ditto...

If this blower fits, I am willing to replace it and clean out that area. Probably needs to be done anyway. Mine blows poorly as well.

[pantera1683]

Any updates on the blower details?

[BOB HDZ]

what happen with the blower motor upgrade?

[-=Jeff=-]

nothing yet, I have not gotten to it

[USAFPILOT]

Well, hurry up an make some time. We all want to know! :cheers:

[pantera1683]

the 90s suburbans (up through 1997) use a 1 wire Blower motor..

was it front or rear AC blower?

any more info would be GREAT

I've done my own research on the blower motor and it looks like the one that will work for the ZR-1 is the one for a late 90s Pontiac Bonneville/Buick Lesabre. It has the correct plug. The Suburban/Tahoes do not have the correct plug. As far as I can tell everything is the same except for the shaft length, it's longer by 3/16".

[-=Jeff=-]

I have to wonder is the squirrel cage was used as well, not sure the motor will make a difference but that cage might

[pantera1683]

Wouldn't the motor have to be more powerful to push more air through a larger area quickly?

[-=Jeff=-]

Wouldn't the motor have to be more powerful to push more air through a larger area quickly?

only if it runs at a faster RPM at a given Voltage.

Assume you have C60 with the 4 speed fan.. also assume 12V (simpler for the example)

so Speed one is 3v, 6v, 9v, 12v, if the RPM at 12v is 300RPM, then it wil be less at a lower voltage. if the suburban or Bonne fan is faster at 12v then it would work better. If both are the same speed at the same voltage, then maybe the squirrel cage is pitched differently

[pantera1683]

My problem is the fan seems to blow the same on settings 6-10 as it does on 5. I think the blower motor isn't spinning any faster at the higher settings.

[-=Jeff=-]

That could be the blower module.. I might have one, I need to look

[pantera1683]

Jeff, clue me in, what's a blower module and how do I check it?

[-=Jeff=-]

Blower module is between the control head and the Blower in a C68 car.. on my C60 it is a resistor network ( 4 speeds) for the C68 it is an electronic module..

there should be a Diagnostic chart for your issue in the FSM

[pantera1683]

I'll check it out, thanks.

[pantera1683]

Update: I ran the diagnostic check and there were no codes stored. I checked the blower ouput on te different fan settings with the ignition on and engine off and the blower motor does increase output through each of the fan settings. The problem is the outpur is very weak, that's probably why I couldn't tell any difference while driving.

[-=Jeff=-]

Pantera, maybe your motor is bad..

if you swap let us know how it works out. I am debating on ordering a Suburban Squirrel Cage to see if it will fit in our air box. not convinced 100% that the motor will make a difference, but might.

Also I found out the 94-95 ZR-1 and 94-96 narrow body cars used a different Condenser, must be the parallel flow condenser like I have to be installed..

[USAFPILOT]

Did anyone figure out which Suburban parts work or not work? It is getting hot in IAH again.

[-=Jeff=-]

Did anyone figure out which Suburban parts work or not work? It is getting hot in IAH again.

I have not yet.. I have my new condenser installed, I need to replace the Accumulator and pull vacuum and charge still.

I am thinking of trying a Suburban Squirrel cage on the Corvette fan though.

[lakemeadzmonster]

:saluting:Some real good deals floating around on ebay for rebuilt clutches, and new ac compressors some without clutches. Maybe clutch slipping?

Your Climate control head will show stored diagnostics. Some how to's on Zr1registry.net
J.

[Bill]

Just spotted this thread and am having similar problems. The idea of the suburban blower sounded interesting. I checked both on Kragen autoparts. These are the blowers on the '90 ZR-1 and the '95 suburban. I'm not sure which one would move more air.
http://i137.photobucket.com/albums/q226/bsoomann/Clipboard.jpg

[Ccmano]

Has anyone installed this blower motor and did it help?

Now that we've had our first 100' days here in SoCal I'm interested in this again.

I just checked my blower motor and noted that it's getting 11.4 volts on fan speed 10 with the A/C on at idle. Seems about right in terms of voltage. Anyone else checked their's for comparison? Any idea what amperage it should be pulling?

It's still an issue of air volume for me, it gets plenty cold.

:happy1:

H
:fahne:

[-=Jeff=-]

I have not, my AC is still not charged yet..

[pantera1683]

I bought the blower motor last year and never changed it out. It looked like it would be a hassle to swap it out. I don't drive my Z daily anymore so I just put it on the backburner.

One thing I should mention is that I wrapped my headers with heat blankets and wrapped the ecm with a thermal blanket and my car runs a lot cooler, the AC works better, and the heat related electrical gremlins are gone.

[GOLDCYLON]

I bought the blower motor last year and never changed it out. It looked like it would be a hassle to swap it out. I don't drive my Z daily anymore so I just put it on the backburner.

One thing I should mention is that I wrapped my headers with heat blankets and wrapped the ecm with a thermal blanket and my car runs a lot cooler, the AC works better, and the heat related electrical gremlins are gone.


Its a simple job just relax the inner wheelwell bolts in order to get the motor and the squirrel cage out. Its a 45 mins job top. Make sure you make note of the condensation orafice tube location. Very simple.