about 91 240sx a/c problem please help...

[Roger_cha]

i have a 91 240sx with a ka24de.. everything is stock no mod yet.. the problem that i have is my a/c... i retrofit my ac into r134 now.. the problem that i have is when i drive the car it blows cold but when i come to a stop it blows hot like the ac was shut off... any suggestions thanks...

[Roger_cha]

any suggestion would help...

[onosqv]

could be a clogged and/or dirty condenser & make sure the a/c fan kicks on when you turn on a/c.

[Roger_cha]

yea the ac fan kicks on when i turn it on... but i dont have the water pump fan.. i took it off.. would you think that might cause the problem... maybe the clutch fan isnt enough to cool down the condenser...

[onosqv]

yea the ac fan kicks on when i turn it on... but i dont have the water pump fan.. i took it off.. would you think that might cause the problem... maybe the clutch fan isnt enough to cool down the condenser...

think you found ur problem. common sense says yes - just think about it.

moving = don't really need fans = a/c cold

not moving = kinda/sorta need fans, but obviously hotter = a/c hotter

hmmmmmmmmmmmmmm

[Roger_cha]

well ill give it a try and let ya know how it turns out...

[silpena]

yeah igo with the clutch fan being back on. sounds like ur building up too might high pressure in the a/c system.

[Roger_cha]

no i have the clutch fan on but not the water pump fan...

[Roger_cha]

yep i try it but it seems no different... still the same...

[onosqv]

no i have the clutch fan on but not the water pump fan...

what?

the stock clutch fan is attached to your water pump... i'm confused.

[Roger_cha]

the clutch fan is on the radiator... i dont have the fan that goes on to the water pump... i only have the one that connects to the radiator...

[onosqv]

the clutch fan is on the radiator... i dont have the fan that goes on to the water pump... i only have the one that connects to the radiator...

sorry to inform you, that's not referred to as the clutch fan, that's the a/c condenser / auxilary fan.

The clutch fan is connected to the water pump. that is the fan we are telling you to reinstall (or get an electric fan for the radiator - a real one, not a/c condenser sizing fan).

[silpena]

agrhhh dud i was like wtf becuase u conused me on what u ere saying. So now i think ur issue is... put ur clutch fan back on. How are u even driving without ur clutch fan at all? electric fan? ur crazy for that.

[Roger_cha]

well i guess some people id parts different from other people then... the people that i knoe that they id the clutch fan as the on that connects to the radiator... and yea i have try to hook that clutch fan that you guy said that it goes on to the water pump and still the same thing...

[onosqv]

First things first - when you put back "the fan that attaches to the water pump", did you also put back the upper & lower radiator shroud?

If you did reattach the shroud, then there is something wrong w/ your cooling system or your a/c system causing it to overheat.

From here, I'd try to bleed/flush the coolant and see if that helps.

Beyond that, you will need to seek professional help or consult the Factory Service Manual.

well i guess some people id parts different from other people then...

Yea, you and the people you know id parts wrong... This is not a part that is "open to interpretation. Look up what a clutch fan is...

From Popular Mechanics: "The fan clutch operation is regulated by a valve that is opened and closed by a thermostatic spring. The valve controls the flow of a viscous silicone fluid between chambers in the clutch assembly."

How to replace a clutch fan



See the mechanical piece in the center? That's the clutch. There is a thermostatic spring in there (i.e. the controlled part) of the fan depending on engine speed. The fan attached to the radiator just turns on w/ the a/c button & on again when the ecu tells it that the car is too hot - no variable speed. Show me where the thermostatic clutch is on your "fan on the radiator".

[Cone Junky]

You need all the fans that came on the car and/or a substitution. The mechanical fan clutch that is hooked up the the water pump pulley is very important unless you switch to electric fans. The small electric fan on the condensor is only an auxillary fan and not capable of completely cooling the cooling system, especially if you have the A/C on.

Your symptoms describe the perfect scenario of the fans not working properly.