I could too, until I turned on the A-C

 

Gil and anybody else that wanted to know the part numbers that I used. These parts would not for work for you. My application uses a reverse rotation serpentine belt system Mfg. by Vintage Air for use on Corvettes and other cars that have a restricted area to work in. It's my understand that they designed it this[reverse] way to keep the system compact which it is.
Dennis

 

Yep, all single belt serpentine systems that have both Alt and A/C use not only a reverse fan, but also use a reverse waterpump off of a 88-91 Corvette. Just no practical way to get the belt to pass over the waterpump pulley in the normal direction of rotation. I know of no single belt serpentine systems that do not use this same setup.
It is near impossible to find a clutch to work with the fan, as most all clutches are setup for a 5/8" pilot from the waterpump, while the late-model Corvette water pump uses a 3/4" pilot. I have just bored the clutch out to 3/4" pilot and they worked fine. The clutch really keeps the fan noise down on the highway. Flex-a-lite makes a really good stock-type fan for reverse rotation that will move a huge ammont of air when the clutch is activated. It is # 5917, and is not a flex fan, but must be used with a thermal clutch, or the roar will drive you to drink!

Regards, John McGraw

 

if you may allow me .I just bought c1 59 with standrd engine 283/230 and import it to Qatar where out side temp reach 125F in summer right now it is 110 F and my car had originally 4 blades 17 in and temp indication in the car was showing almost 200 and rising so I had change it to 18in 6 blades fan from GMC 1985-1993 made in Brsil .
I wa shocked to find out tat the temp was droped to t-state level even in traffic gos below 180F amazing
If you need more inform about the fan part # you are most welcome .

but there is one thing I need to highlight and I need the expert view on this . the new blads are heavy will it affect the water pump?

thanks
Omar

 

if the fan is properly balanced and the blades all have the same pitch (in other words, if it is not damaged...), then your water pump should be fine.
Bill

 

Wouldn't that pull in hot air from the engine compartment?

 

it shouldn't, BUT it will work best (maybe only...) if the a/c condenser has it's own fan. the a/c condenser sits on the front side of the radiator and is separated from the engine compartment by the radiator and the radiator support.

i recently spaced my condenser out an additional inch (more would be better, but i'm limited by working room) from the radiator; the jury is still out as daytime temps have dropped dramatically and my 'hotter than i'd like it' problem only occurs around town in traffic. so, it may be next year before i really know if it helps; early indications are that it has stabilized temps a bit, and the heat soak temp rise from shutdown seems to pull down quicker.



Bill

 

My 66 cracked 5 stock GM waterpump housings. The failures occurred each time I brought the engine past 4000 rpm with the air conditioner engaged (and pulling hard on the waterpump pulley). The castings cracked at the front bearing every time.

I am now using a Stewart cast iron pump that bolts right on in place of the factory pump, but has a reinforced housing and a larger front bearing. I recommend it if you have problems

 

No.

The condenser is in front of the radiator support. The drawing is somewhat misleading for the expected airflow direction.

The normal puller fan develops a negative pressure area downstream of the radiator. All the airflow travels from high pressure to low pressure. Airflow travels inward from the sides of the condenser to mix in the gap between the condenser and radiator, before being pulled through the radiator.

The condenser has high bypass ratio or bypass factor, much more than the radiator. This means a high ratio of untreated air (air not picking up heat in this case) passes through the condenser compared to the percentage of treated (heated) air. This is one reason why the condenser is so large, by design, compared to the evaporator (or cooling) coil inside the AC blower ducting - because it is designed to bypass a high ratio of untreated air. The bypass air and heated air mixes after it leaves the condenser, leaving only mildly heated air to continue through the radiator.

Take the two effects of the above paragraphs and combine them: untreated airflow entering the sides of the gap between the condenser and radiator, mixing with the high bypass percentage of airflow traveling through the condenser. The result is the temperature gain of the mixed airflow between the condenser and radiator, the air entering the radiator, is much lower than if you close coupled the condenser and radiator heat exchange surfaces.

A wider the gap between the condenser and radiator allows more untreated (unheated) mixed airflow and a lower airflow temperature entering the radiator. Good for radiator heat exchange.

If a condenser is replaced with a model that is larger in face area (that holds the same volume of refrigerant) it can be designed to have a higher bypass ratio and the temperature of mixed airflow on the downstream side of the condenser will be lower. Again, good for radiator heat exchange.

Clear as mud?

I trust this helps.

 

Got it. The way the radiator sits in a C3, if you don't have some insulation along the sides of the radiator you'll be pulling in all sorts of air from the engine bay, since the radiator sits back from the core support by about 1/2". I've never had the opportunity to study the C2 radiator mounting that closely.

 

What a greeat thread. So much good info from all directions. THIS is why this forum is so great! Thanks, Glenn

 

It would have been really nice if the drawing had this small addition:



wmf62, you are correct... with a big gap between the condenser and radiator, you need a fan on the condener if you want any a/c at idle (with no seal between condenser and radiator).

 

Excellent idea! good work Bill

My drawing may be flawed but the illustration was simply to say, don't seal up all the gaps between the radiator and the condensor. The radiator would like some fresh air. Not to be confused with sealing the radiator to the core support, that is a good idea. Not so much for drawing in compartment air, but rather stoping air from just going around the radiator instead of thru it.

 

Just for complete clarity:



And in the left drawing, the core support position will not make a difference--i.e. the condenser can be inside or outside the core support.

 

The condenser is never inside the core support, aways on front side of core support.

 

Tom, any pic or diagram of a 327 with A/C and Powerglide transmission cooler? I was thinking of adding A/C last spring but did not have the courage. Too much happening in front of the rad.

 

Okay, whatever you say. I give up, tell people anything you would like.

At this point I'd be tempted to repeat your " Whatever", but that whole 'do unto others' thing...

 

Uhhh, the condenser is always on the front side of the core support.

 

Paul, I mentioned a friend earlier in this post who lives here in the desert with a big block, auto, air, and he has no problems. The only thing different, is the license plate is below the grill. This is the way GM mounted it, not to impede the air in front of the grill knowing full well they where going to need all the air they could get.

In addition someone added that the fan had more blades to support this application.
Dennis

 

Yes, that's fine. I didn't say it wasn't.

I said "i.e. the condenser can be inside or outside the core support." Are we going to argue symantics of the word "can" ?? Or is the fault with my use of "i.e." instead of "e.g" ??