AC in my 71 - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Andy4639 · 07-23-2011, 06:30 AM

It's been so hot lately I decided the 71 AC needed some work.
It's been awhile since I have done anything with the AC in my 71 I can't remember how the flapper in the cowl is suppose to be when the air is on?
Can some one please tell me.

I have a roll of this Mastic tape to seal up around the box on the fire wall.

Andy4639 · 07-23-2011, 11:06 AM

Well I sealed the flapper off completely and drove the truck to work this morning. My fan had no air movement hardly. I had the passenger side vent inside the cab shut also though.
I will open it this afternoon before leaving work and see if it makes any change in the cab air movement.

Richard H. · 07-23-2011, 11:25 AM

Right ,open the vent inside and it will recirculate.

Andy4639 · 07-23-2011, 11:32 AM

The fan motor had hardly no air blowing out of it. Will this help it with more air? I may need to put a few holes in the cowl area maybe!

**leddzepp** · 07-23-2011, 03:58 PM

Cowl vent closed. Kick panel vent open. This is how they should be with the A/C on.

Andy4639 · 07-23-2011, 05:27 PM

I went out to the truck at work and it was 98 degree's according to the temp senor in the truck.

I opened the passenger side kick panel vent and it was a nice ride home. The AC has worked good in the past just didn't cool down as good as it could because the cowl vent was always opened. Now it was at least a few degree's cooler on the ride home today than before.
I only drive about 15 miles each way so I guess it will be even better on a longer ride!

chevytruckluver · 07-23-2011, 10:26 PM

The vent in the cowl is how the truck get air from the outside, the factory air system will close the cowl vent and open the kick panel vent to re-circulate the inside air. In addition when in the a/c mode the heater control valve is closed.

**leddzepp** · 07-23-2011, 11:06 PM

Check to make sure your heater valve is closed. If the cowl panel was open, there is a good chance your heater valve is open also, as they are both vacuum controlled. If the heater valve is open, your air will not get as cold as it could.

Andy4639 · 07-24-2011, 05:51 AM

Guy's the heater is closed. I have a manual valve installed as well. It's closed. The reason the flappers aren't in place is I bought everything out of a junk truck. The flappers were both broke so I didn't get them. They were never installed. I plan on fixing this though. The drivers side will work as far as fresh air goes and the back glass opened when I need it.
This morning the ride back to work was very nice. Truck was good and cool since sitting in the garage all night! I will be fixing all the small holes in the fire wall also.

Andy4639 · 07-24-2011, 12:03 PM

OK first off the pictures suck because they are off my blackberry. But I think you will understand them. I stopped by O-riley's on the way home today and bought a thermometer to see how the AC was performing. I think it's doing fine for a 30 year old truck.

The out put temp was 40 degree's as long as I was moving.
It's hard to take that small of a picture when driving at 60MPH!
I still have some work to do like sealing up all the fire wall small holes and I may buy all new duct also.

Andy4639 · 07-25-2011, 08:44 AM

Did a little more fine tuning yesterday on the AC. I hope this forces more air through and cool's a little better! I had these in before and took them off back when I had the truck painted the last time. I just reinstalled them yesterday.

Going to look for a Junkyard fan tomorrow. Any suggestions on what to look for?

I know a lot of you use a Jeep fan.

I have the clutch fan now and a small fan my brother had given me way back when. I want a fan in front of the radiator. I don't want to take the whole front end apart to install it.

Andy4639 · 07-26-2011, 07:25 AM

Drove the truck again with the inserts and it helped on the sitting still AC temp. It stayed right at 50 degree's instead of the old 55-65 while at a light. 95 degree's outside. Going to try and find a fan later today are tomorrow morning.
Can anyone think of anything else I can do to get this temperature down inside the cab?

mrein3 · 07-26-2011, 07:38 AM

Quote:

Originally Posted by Andy4639

Drove the truck again with the inserts and it helped on the sitting still AC temp. It stayed right at 50 degree's instead of the old 55-65 while at a light. 95 degree's outside. Going to try and find a fan later today are tomorrow morning.
Can anyone think of anything else I can do to get this temperature down inside the cab?

The only thing I can think of is if you're running an original condenser and using R134a for coolant. If that is the case you might want to look for a modern condenser. When R134a first came out ALL the cars running it didn't cool as well sitting at a stop sign without lots of air blowing across the condenser. In the really new stuff out there they seemed to have gotten over that with a better condenser design.

Andy4639 · 07-26-2011, 08:43 AM

I have a 134-A condensor made for the truck. It came with the kit I bought.
Sorry should have said that. I put all new stuff in about 2-3 years ago when I converted it to 134-A. The evaperator is the only thing I didn't change out. Didn't want to take the truck apart when I did it. That may happen over the winter though!

Andy4639 · 07-26-2011, 09:38 PM

I went to the junkyard today and bought a electric fan out of a mini van. I have it hooked up to the low speed for now. It's keeping the truck at 40 degree's inside when sitting at a stop light. It's on anytime the AC is on. it moves a lot of air on low speed.
Sorry no pictures.

**nightmare** · 07-26-2011, 09:59 PM

I need to convert my AC over to 134A. Do you happen to have a list, or a link to all the parts that I might need for this conversion? Maybe a build thread or so?

EDIT: Nevermind, found what I was looking for.

07-23-2011, 06:30 AM	#1
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	AC in my 71 It's been so hot lately I decided the 71 AC needed some work. It's been awhile since I have done anything with the AC in my 71 I can't remember how the flapper in the cowl is suppose to be when the air is on? Can some one please tell me. I have a roll of this Mastic tape to seal up around the box on the fire wall. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

07-23-2011, 11:06 AM	#2
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: AC in my 71 Well I sealed the flapper off completely and drove the truck to work this morning. My fan had no air movement hardly. I had the passenger side vent inside the cab shut also though. I will open it this afternoon before leaving work and see if it makes any change in the cab air movement. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

07-23-2011, 11:25 AM	#3
Richard H. Spanked once Join Date: Oct 2006 Location: Intheshop, Indiana Posts: 969	Re: AC in my 71 Right ,open the vent inside and it will recirculate. __________________ The ole 350 budget build.

07-23-2011, 11:32 AM	#4
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: AC in my 71 The fan motor had hardly no air blowing out of it. Will this help it with more air? I may need to put a few holes in the cowl area maybe! __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

07-23-2011, 03:58 PM	#5
leddzepp Moderator Join Date: May 2007 Location: Southern Cal Posts: 19,996	Re: AC in my 71 Cowl vent closed. Kick panel vent open. This is how they should be with the A/C on. __________________ 1972 C/10 Cheyenne Super SWB. Restored, loaded, slammed. 1968 C/10 50th Anniversary LWB. Unrestored, stock, daily driver/work truck. RIP ElJay RIP 67ChevyRedneck RIP Grumpy Old Man

07-23-2011, 05:27 PM	#6
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: AC in my 71 I went out to the truck at work and it was 98 degree's according to the temp senor in the truck. I opened the passenger side kick panel vent and it was a nice ride home. The AC has worked good in the past just didn't cool down as good as it could because the cowl vent was always opened. Now it was at least a few degree's cooler on the ride home today than before. I only drive about 15 miles each way so I guess it will be even better on a longer ride! __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

07-23-2011, 10:26 PM	#7
chevytruckluver Eat, Sleep, Drive a Chevy Join Date: Apr 2010 Location: the town of the cow, Texas Posts: 1,152	Re: AC in my 71 The vent in the cowl is how the truck get air from the outside, the factory air system will close the cowl vent and open the kick panel vent to re-circulate the inside air. In addition when in the a/c mode the heater control valve is closed. __________________ Trey Silence may be Golden, but Duct Tape is Silver! 72 Short Step 57 "big window" short step

07-23-2011, 11:06 PM	#8
leddzepp Moderator Join Date: May 2007 Location: Southern Cal Posts: 19,996	Re: AC in my 71 Check to make sure your heater valve is closed. If the cowl panel was open, there is a good chance your heater valve is open also, as they are both vacuum controlled. If the heater valve is open, your air will not get as cold as it could. __________________ 1972 C/10 Cheyenne Super SWB. Restored, loaded, slammed. 1968 C/10 50th Anniversary LWB. Unrestored, stock, daily driver/work truck. RIP ElJay RIP 67ChevyRedneck RIP Grumpy Old Man

07-24-2011, 05:51 AM	#9
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: AC in my 71 Guy's the heater is closed. I have a manual valve installed as well. It's closed. The reason the flappers aren't in place is I bought everything out of a junk truck. The flappers were both broke so I didn't get them. They were never installed. I plan on fixing this though. The drivers side will work as far as fresh air goes and the back glass opened when I need it. This morning the ride back to work was very nice. Truck was good and cool since sitting in the garage all night! I will be fixing all the small holes in the fire wall also. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

07-24-2011, 12:03 PM	#10
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: AC in my 71 OK first off the pictures suck because they are off my blackberry. But I think you will understand them. I stopped by O-riley's on the way home today and bought a thermometer to see how the AC was performing. I think it's doing fine for a 30 year old truck. The out put temp was 40 degree's as long as I was moving. It's hard to take that small of a picture when driving at 60MPH! I still have some work to do like sealing up all the fire wall small holes and I may buy all new duct also. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

07-25-2011, 08:44 AM	#11
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: AC in my 71 Did a little more fine tuning yesterday on the AC. I hope this forces more air through and cool's a little better! I had these in before and took them off back when I had the truck painted the last time. I just reinstalled them yesterday. Going to look for a Junkyard fan tomorrow. Any suggestions on what to look for? I know a lot of you use a Jeep fan. I have the clutch fan now and a small fan my brother had given me way back when. I want a fan in front of the radiator. I don't want to take the whole front end apart to install it. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

07-26-2011, 07:25 AM	#12
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: AC in my 71 Drove the truck again with the inserts and it helped on the sitting still AC temp. It stayed right at 50 degree's instead of the old 55-65 while at a light. 95 degree's outside. Going to try and find a fan later today are tomorrow morning. Can anyone think of anything else I can do to get this temperature down inside the cab? __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

07-26-2011, 08:43 AM	#14
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: AC in my 71 I have a 134-A condensor made for the truck. It came with the kit I bought. Sorry should have said that. I put all new stuff in about 2-3 years ago when I converted it to 134-A. The evaperator is the only thing I didn't change out. Didn't want to take the truck apart when I did it. That may happen over the winter though! __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.

07-26-2011, 09:38 PM	#15
Andy4639 Old member Join Date: Jan 2002 Location: Liberty, & Garden City S.C. , U.S. Posts: 19,936	Re: AC in my 71 I went to the junkyard today and bought a electric fan out of a mini van. I have it hooked up to the low speed for now. It's keeping the truck at 40 degree's inside when sitting at a stop light. It's on anytime the AC is on. it moves a lot of air on low speed. Sorry no pictures. __________________ 1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver Seeing the USA in a 71 Upstate SC GM Truck Club 2013,14 and 2016 Hot Rod Pour Tour http://upstategmtrucks.com/ Get out and drive the truck this summer and have some fun! It sucks not being able to hear! LWB trucks rule, if you don't think so measure your SWB! After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.



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