ed_hdz

I have searched endlessly and haven't found anybody experiencing this issue. I have a 94 EX coupe with a b18b1 and original d16 compressor. The compressor, clutch, drier, and expansion vale are new. The evaporator was removed, cleaned, and then re-installed. The system was flushed, a vacuum was pulled and then filled with 17 oz of refrigerant and about 4 o of oil. The low side pressure reads between 35-40 at idle and high side is up of 280 at idle. The vent temps at idle are around 60-75 *F. However when the car is moving, the temperature drops and at highway speeds vent temps are between 38-44*F. The condenser fan engages when the a/c is on and the radiator fan cycles on and off as usual. The A/C works fine even driving around at 30 MPH in 4th gear at about 1400 rpm. But as soon as I come to a stop the temperature starts shooting up. I placed a coloring book in front of the condenser with the fan on and the fan is able to hold it in place, so it looks like there is sufficient air flow through the fins. When i hose the condenser down at idle it starts cooling much better. This makes driving in Texas traffic a horrible experience.
I've tried just about everything. Any ideas as to what it may be?

Former User

Maybe the condenser is bad.

Bradshaw

sounds like the condenser is all thats left lol

and i feel ya on that texas heat man. no a/c in either of my vehicles and my a/c in my house went on the fritz today.. gonna be a long summer i feel...

Silvertune

Spray the condenser out for starters. Pull the fan off (since its really easy anyway) and take your hose and spray the condenser out from the back towards the front of the car. Its unbelievable how much dirt and crap will come out.

Otherwise it sounds like heat soak to me. A cool trick that I've done to every car that I've ever owned: go to your local hardware store and get some pipe insulation and insulate the aluminum AC lines. Makes a HUGE difference especially when its hot out. AC will work almost instantly and even when its raging hot out you won't lose so much to the heat of the engine bay.

strategy400

Could it be the crank pulley on the B18 is a different diameter than the original D16 pulley and thus does not spin the D16 compressor fast enough at idle?

That doesn't really sound like Honda (king of same parts on different models) but maybe...

Disclaimer - the following assumes r134a, if your system is r12 you may want to disregard.

Also, 17 oz refridgerant sounds maybe on the low side of the spec (17-19 oz?).

The biggest issue in my mind (and RonJ@HT's et. al.) is why didn't you replace the condenser? You can have one at your door from radiator barn the next day for ~$90. They are pretty easy to install (6 bolts, 2 fittings, ~2 connectors). The bitch is the fitting coming from the receiver/dryer. That one is best attached before the condenser assy. is fully bolted into place to give a little wiggling room. An assistant might be helpful there. Also care must be used especially on the condenser because the fittings bend super easy and might crack. Use 2 wrenches!

Condensers don't flush well because of the parallel flow paths. If your compressor was replaced because it locked up there may be debris in the condenser that hopefully is not now flowing around the system and is possibly reducing the capacity of the condenser. Cooling it with water may return some of that capacity and higher air flow and refrigerant flow when the car is moving could also restore enough capacity to allow cooling. You might want to consider opening the system again and replacing the condenser and receiver/dryer (<- the filter of the system).

Your pressure readings are... different from mine.

Keeping in mind I took these readings with @60 ambient air temp, it just happened to be that cold when I charged the system - my pressure readings go like this at idle:

just before cycle on (compressor off) - 45 low - 100 high
just before cycle off (compressor on) - 22 low - 125 high

after turning off the engine and waiting about 10 minutes the pressure in both sides equalized to about ~67 (The average of your high and low readings is like 158!)

My A/C was uncomfortably cold today.

Your pressure readings sound really high... are you sure you charged in 17 oz? It seems overcharged, which is bad. Possible blockage? Again, hopefully your condenser isn't horribly contaminated. What was the ambient air temp when you took those readings?

I weighed in refridgerant in grams (metric system ftw). The spec on my system was 17-19 oz. or 500-550 grams, I charged in 530 grams.

Using my cheapo harbor freight digital scale and some fancy math (I weighed the full can, charged it in and weighed the empty can) I deduced that each of the 12 oz cans of r134a I purchased contained 330 grams of refridgerant. Google says 330 grams = 11.6404074 ounces, so pretty close.

Therefore a full charge was approx. 1 and 2/3 cans. I used my scale to make sure the 2nd can was 200 grams lighter when done (I set the 2nd can on the scale while charging and watched it count down the 200). The end result was a 330 + 200 = 530 gram charge.

BTW I pulled a 29 Hg vacuum for 45 minutes and let it sit for 2 hours to check for leaks (none).

Anyway, hope some of this ramble helps.

Good luck.

ed_hdz

So I picked up a new condenser and drier from a buddy who gets shop discounts. I'll be replacing them both. I've installed one before so that shouldnt be a problem, but is there anything i can do to ensure the system works really well? At school we have a machine that does everything on it own. It will recover, pull a vacuum, and recharge the system according to what it is set to (in this case 18 oz right?)

Purple-si

im sorry guys maybe i wasnt very clear..the cooling fans for the radiator not for the ac..my fault.

Former User

Are you the OP?