looking for better ac performance

[RLDSL]

Hey what is an A/c Specific forum? I've got some off-topic vehicles to touch up the air on. Oh and I'm always interested in learning more.

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www.aircondition.com has a forum secton that is visited by a number of ac techs or feel free to PM me about other vehicles. I used to work in a specialty auto ac shop where we worked on nothing but exotics and have done all kinds of custom ac work. I halfway know how to make cold
Now if I could just get a stinking company in FL to send out the friggen new AC compressor units for my house that are on order that they keep jerking us around about, I'd be REAL HAPPY. wE'VE been without ac at the stinkin' house for around 3 weeks now after 2 compressor units decided to commit suicide at almost the same time right in the middle of this heat wave and weve had to move into our 5th wheel while waiting on parts. It thoroughly sucks knowing HOW to fix the damn thing and not being able to . Lowest temp weve seen in the last 2 weeks was 104 and its been up to 114 a couple times It was around 110 again today and we finally just jumped into one of my nice freezy cars and drove around all day just to break the heat stroke cycle ( ive got a very low body temp and so do my kids, put us out in a blizzard in a t shirt, no problem, but when the mercury goes above 75 we start getting weak ... theres a reason I developed such an interest in making things cold

 

[The Warden]

( ive got a very low body temp and so do my kids, put us out in a blizzard in a t shirt, no problem, but when the mercury goes above 75 we start getting weak ... theres a reason I developed such an interest in making things cold

You guys and me both...and people look at me like I'm crazy.

Is there any chance of you coming back out to CA in the not-too-distant future? If not, I may have to go out there some winter and see about optimizing my a/c system

 

[92F350CC]

I've done Arkansas in summer with no A/C in my truck or house...it's terrible.

At least these trucks didn't come with leather seats. My A/C is weak in my Lexus and it's killing me to drive it.

 

[bob_442]

FWIW: I have a "Chummins". The A/C compressor is a brand-new Sanden SD-508. The A/C performance was lackluster.
My engine came out of some agriculture equipment (I know not what -- I bought the truck used -- not from the original owner
that did the conversion). My engine is governed at 2100 RPMs. I realized that the compressor is probably only being turned
at half the speed it normally would be. The fact that the A/C did not cool at all at idle, and only a little bit at cruising speed
helped confirm my diagnosis. The obvious solution would be to play with the pulleys, but I doubt the pulley I need
exists -- maybe it could be machined though. So, I tried swapping out the orifice. The orifice was the correct one for the
vehicle -- the GM white/white, 0.072" orifice. I replaced it with a Ford, orange, 0.057" orifice. I haven't driven it on the
hottest of days yet -- but I have driven it when the A/C was needed, and it works a lot better. I could probably still use the
custom pulley (or a different compressor), but what I have now is much improved -- the modification provided a lot of
bang for the buck.

FYI: The Ford blue orifice is 0.067", and red is 0.062".

 

[RLDSL]

You guys and me both...and people look at me like I'm crazy.

Is there any chance of you coming back out to CA in the not-too-distant future? If not, I may have to go out there some winter and see about optimizing my a/c system

Not planning any west coast trips for a while, next big trip we're going North East, but you're always welcome to drop by for some upgrades ( just try to do it when it's not to friggen hot out)

 

[RLDSL]

FWIW: I have a "Chummins". The A/C compressor is a brand-new Sanden SD-508. The A/C performance was lackluster.
My engine came out of some agriculture equipment (I know not what -- I bought the truck used -- not from the original owner
that did the conversion). My engine is governed at 2100 RPMs. I realized that the compressor is probably only being turned
at half the speed it normally would be. The fact that the A/C did not cool at all at idle, and only a little bit at cruising speed
helped confirm my diagnosis. The obvious solution would be to play with the pulleys, but I doubt the pulley I need
exists -- maybe it could be machined though. So, I tried swapping out the orifice. The orifice was the correct one for the
vehicle -- the GM white/white, 0.072" orifice. I replaced it with a Ford, orange, 0.057" orifice. I haven't driven it on the
hottest of days yet -- but I have driven it when the A/C was needed, and it works a lot better. I could probably still use the
custom pulley (or a different compressor), but what I have now is much improved -- the modification provided a lot of
bang for the buck.

FYI: The Ford blue orifice is 0.067", and red is 0.062".

Ditch the fixed orifice valve and pop a variable orifice valve in there, Low speed performance is where those things shine, that is what the guy designed them to take care of the problem of. Add a electric pusher fan and you are well on your way to a prime ac system. Now, since your truck already has a Sanden 508, you are in a unique position to pop a better upgrade compressor on there. The 508 is 5 cyl 8 cu in, now if you put a 709 sanden or one of its clones in there( dont shy away from quality new clones, Ive never had a failure * when installed properly* . The 709 has 7 cylinders and 9 cu inches displacement, and cools WAY better than the 508 and has the interesting side effect of putting less drag on the engine under accelleration , great low speed performance and it's a direct bolt in replacement for the 508. You could go nuts and pop an upgrade condenser in there as well, but a pusher e fan rigged to come on with the compressor should take care of most issues.
If you decide to upgrade your compressor, Jon at www.nostalgicairparts.com has great prices on the things. He can also fix you up with upgrade condensers if you decide you need one later after trying everything else.

 

[RLDSL]

I've done Arkansas in summer with no A/C in my truck or house...it's terrible.

At least these trucks didn't come with leather seats. My A/C is weak in my Lexus and it's killing me to drive it.

We finally got all the parts in for the house and it just about killed me being out in 110+ heat for 4 days putting that sucker in, I've been in bed since, recovering from multiple heat stroke events.... but it's nice and cool in here now at least

Lexus ac is generally pretty darn good . If it's weak, most likely a charge issue, but better take care of that and if the charge is low, make sure to add a bit of oil so you dont kill your compressor . If you dont have a fancy gauge set, one of those large cans of refrigerant at the parts store that comes with a re usable low side gauge is a great way to get a reading on system pressure, for about $18 hook it up and check it out, and if low, pop the can and let the juice flow ( they even have most with an oz or so of oil in them to replace oil lost over time ) Ket it run at least 10 minutes on high to equilize before taking a reading. THose are handy setups if you don't have full manifold gauges
If its weak but still functioning, chances are, that's all it is, but if you get acceptable pressure readings, PM me

 

[92F350CC]

Yeah, she was low. I vacuumed her out and replaced the R134 and oil. She works pretty darn well now, unless I leave her sitting in the sun all day in the 110 heat, then she takes her time getting cold, but she does get there.

 

[remington88]

Ac in your cars?? What is this. I have never had working ac in anything. I could just to lazy and cheap to fix it.

 

[Devon Harley]

In san Diego traffic its nice to have a/c the window down doesn't cut it. In Missouri worked just fine. I just re did my whole a/c system must say wow if you have a properly workin a/c system in these trucks they do work well I'm impressed. Total cost in parts was around 500.

 

[MIDNIGHT RIDER]

My engine is governed at 2100 RPMs.

Do you know which injector-pump you have ??

If your injector-pump is a rotary Bosch VE, it is a very simple matter to replace the governor spring.

Various governor springs are available including 2700-RPM, 3200-RPM, 4000-RPM, 5000-RPM, and even 6000-RPM.

Factory-issue on a 1989-1993 1st Generation Dodge/Cummins is 2700-RPM.

On a working truck, the 3200-RPM governor spring is ideal.

Also, about 300-RPM gain is available by simply adjusting the "high-idle" limit screw, easily accessible on the larboard/out-board side of the pump; it is the screw that the throttle-lever comes against at full throttle.

The high-idle screw only requires a 10-mm wrench and straight screw-driver; don't go too much at a time; half-a-turn makes a lot of difference.

 

[smolkin]

Another simple item, add a shut off valve to the heater core. That itself made a big difference in mine.

Are there any known issues with the Explorer-type shutoff? I'm only asking because I want one but just yesterday I came upon a freshly broken-down Tahoe while at work...the guy was confused, it "acted wrong and then overheated" he said. I noticed the problem right away-- his vacuum-operated heater bypass had exploded, causing him to lose vac and coolant (2 things I really need in my truck). Hopefully the Ford ones are better?

 

[subway]

no you have to watch what you put in there, some of the valves are plastic and can break down over time, others shut off almost all the flow but not all. we do not need flow through the heater core for proper engine cooling like other vehicles. the best most robust method is to put a nice metal 1/4 turn valve in from a hardware store. it is not automatic like the ranger valve upgrade but it is MUCH less likely to have any problems with breakage and leakage. you should only need to switch it twice a year, close it in the summer when it warms up and open it when fall comes.

 

[my85ford]

Subscribed thanks

 

[idi traveler]

I'm a big fan f the ball valve.