Fan clutch mod/over heating/water temps

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We have done mine twice...once at your shop early on and then once at truckworks at he CSC club work day. I don't remember which fluid but I remember you put thicker than you had put in others. At that time you checked over the ac condenser and rad and didn't think it was bug littered I have kept that pretty clean. I'm not sure about the air flow around the tires...I will check.

i have never replaced the dryer...
I will get a new cap this week, I checked around the injectors and exhaust manifold and didn't see any gas etc. I have gotten a code for o2 sensors bad, however, it hasn't come back since cleared. I might replace them, I think I might have some small exhaust leaks around that area from my truckworks exhaust so that might be throwing the codes as well.

If my temps seem normal than maybe it's just poor ac performance. Like I said I haven't had it boil over or shut off the ac completely since the last time we changed the fluid in the fan clutch. I figured it would do the same thing because it kept going up and I intervened at 212 but since that time I can get the temp up that hi...I will keep working on it ;)
But as the temp goes above 202 the ac gets warmer and warmer till its not cold at all. While I was sitting in the truck reading and watching the temp gauge yesterday I had the ac on full and was sweeting with the temp gauge at 206-207 so the ac was pretty ineffective at those temps....so if those are normal temps then my ac has problems...not my cooling system

am I making any sense??
 
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Makes sense to me.

Check the charge and the system.

If it's still being lame, then move some more air at the condenser, one way or another.

A sacrifice to the artic gods couldn't hurt either :cool:
 
clarkrw3 said:
We have done mine twice...once at your shop early on and then once at truckworks at he CSC club work day. I don't remember which fluid but I remember you put thicker than you had put in others. At that time you checked over the ac condenser and rad and didn't think it was bug littered I have kept that pretty clean. I'm not sure about the air flow around the tires...I will check.
Click to expand...

You should have pretty good amount of hot airflow coming out near the tires and back as far as the driver's door area. By the truckworks day I was getting pretty aggressive with the fluid, now more so, but what you have should work. Mine is 10K and thinking about going to +15K, the fluid goes bad with use, is cheap, so changing it every few years is probably a good idea. But yours has few miles on it, don't see it being bad, if you want to go thicker I have zero problem with helping on that.

Yours will have much higher solar heat load compared to mine, this isn't going to help.

clarkrw3 said:
i have never replaced the dryer...
...
If my temps seem normal than maybe it's just poor ac performance. Like I said I haven't had it boil over or shut off the ac completely since the last time we changed the fluid in the fan clutch. I figured it would do the same thing because it kept going up and I intervened at 212 but since that time I can get the temp up that hi...I will keep working on it ;)
But as the temp goes above 202 the ac gets warmer and warmer till its not cold at all. While I was sitting in the truck reading and watching the temp gauge yesterday I had the ac on full and was sweeting with the temp gauge at 206-207 so the ac was pretty ineffective at those temps....so if those are normal temps then my ac has problems...not my cooling system

am I making any sense??
Click to expand...

The only time that the dryer needs to be changed is when the system is opened. When a component is changed, moisture get into the system and the dryers job is to remove it. A simple recharge doesn't require changing it and it's much less important in our dry climate than other places.

All A/C systems make a temp drop from ambient. Say the ambient is 90F and vent is 40, it's producing a 50F drop, now say the ambient is 115F, you would expect the vent to be 65F. But in real life it rarely works that well: At higher temps, especially when relatively dry the system is stressed and efficiency is reduced. When in the sun, the solar gain has to be taken into account, etc.

Unfortunately the 80 was designed as a R12 system and factory "converted". I would rate it as adequate when compared with newer "clean sheet" R134 designs. So to make it work acceptably in our climate everything needs to be in good working order. As Cliff said recharging it would confirm that it has the correct charge. Or test some vent vs ambient temps and post up.
 
Thanks tools...will so asap
 
Anyone know anything about Arizona Auto Air in tempe? Or the south Scottsdale Lexus dealer?
 
The A/C shop that Brian used is Accurate Automotive 480-890-0409. I have never used them, but hear they are good with imports.
 
Tools R Us said:
The A/C shop that Brian used is Accurate Automotive 480-890-0409. I have never used them, but hear they are good with imports.
Click to expand...

Accurate Automotive fixed my A/C system after my compressor and clutch failed - new clutch, compressor, drier, expansion valve, and flushed everything else. They did good work, I'd recommend them.

- Craig
 
Low charge.
BTW, with our "factory converted" AC systems, make sure they just put in the minimum charge. 1.76lbs. I did that (looking for a hard to find pinhole leak) and froze myself out of the truck. That was on Thursday afternoon, around 6 pm.
By Friday, it was merely chilly.
Found my pinhole leak, though. Inside row on my evaporator. $200 i don't have.
 
hj60 said:
Found my pinhole leak, though. Inside row on my evaporator. $200 i don't have.
Click to expand...

i've got an evaporator off the '93. don't know if it's any good because the ac
wasn't working but the po said it was the compressor. it's yours for a six of
guinness if you want to try it (but refunds will be limited to unopened beers)... :beer:
 
I did a couple more tests in the heat of the day. it seems it never goes over 213 at idle even with intake temps over 170. Given at that coolant temp no cold ac is coming out of the vents. I ran it hard and turned off the engine and watched the coolant temp reach 220 and turned in on again and let it idle and within 3-4 min it was back to 212-213. this was with air temp of 112 and intake temps in 175 range. So I think this means it's more of an AC thing and less of a cooling issue. I have it in the shop today to address the AC so we will see what they say. Thanks for all the input guys I will update when I have more info.

Tools....I don't seem to feel any air in the wheel wells but do feel it under the truck.
 
The 175 was just as I was turning it on that came down fast

I just got a call from the shop, everything is in tip top shape charge where in should be etc. Which is good and bad news.

So now, I might increase the viscosity in the fan clutch, hook up the installed JDM pusher fan and the Lexus dealer recommended I put foam between the condenser and radiator to force air to go through both. They said that they had the same problems on some LX 470's and Toyota's fix was to install a pusher fan on the condenser and install foam btw the radiator and condenser. They also stated that my water temps were fine.
 
I'd take the advice from Toyota.

Move the air across the condenser.

If it was me I think I'd try the electric pusher fan before adding more fuel sucking drag on the clutch fan. As many cfm's as you can get in there and run it on a relay so it gets full voltage.

Of course a pusher fan can be a hindrance to air flow when it's not on.:frown:

Look for any potential improvement to make sure the air in front is coming from the coolest possible source, i.e. not sucking air from the engine compartment or the pavement. Just through the grill.

Unless the grill only would be too restrictive. :hhmm:
 
clarkrw3 said:
...hook up the installed JDM pusher fan...
Click to expand...

I keep thinking you might be saying you already have a fan installed, but not hooked up. If so, that's a major air blockage and would explain some of your problem. Either way, hook it up or install and hook it up, it'll help your A/C at idle.

-Spike
 
yes, that's the plan. I have been putting it off because I HATE electrical...and I was trying to find the plug for the fan, which I think I now have at the Toyota Salvage off of University in phoenix. The fan is installed so yes it is blocking air flow right now.

On the way home yesterday in bumper to bumper I-10 traffic it hit 220 and stayed in the 216-218 until the traffic broke up. (sound normal?) then today coming in even in traffic it never went above 195.
 
Just a point of reference for you.
My daily driver is a 46 year old V8 powered truck with an aftermarket R134 A/C system of less than stellar engineering (IMHO).

I run a 190 thermostat, good size brass radiator, 10 lb cap, stock pump and a 9 blade clutch fan in a shroud. Winter or summer the temp gauge sensing at the cylinder head hits 210 and pretty much stays there +/- a few degrees. It never boils over.

The A/C is anemic when the ambient temp gets over 105. That probably translates to at least 150 on the pavement when you're poking along or at a light.

I added a pusher fan to the system last year to give it some help. It did make a difference, but can't make up for a poorly sized condenser in the system. Now it takes a little longer for cooling to start falling off at the vents and it recovers faster once you get a little speed.

But,
If I'm stuck for more than a couple of light changes, it just can't cope. The vent temps start drifting above 50 and won't come back unless I get a good run down the highway. Being inside an uninsulated steel can doesn't help matters either.

It's the best I can do in my situation. If only I had cases of R12 in my closet. :frown:

Point is, there is only so much you can do with system if it has design flaws. (R12 converted to R134) I'm sure the yocals in Texas that designed my R134 A/C system weren't thinking much about the zero humidity furnace we live in when they did it. I asked them about gauge readings once. My ambient temp in front of the grill, in the garage, at night was 122. Response: "My chart doesn't go that high" "Here's a rule of thumb formula, good luck".

It sounds like your cooling system is doing it's job but the A/C has an issue. It also sounds like other owners of the same rig are comfortable, so you've got hope.

Move the air! :bounce:
 
Got the plug for the fan today...tools I will give you a call.

Thanks for the info Cliff, I know I should be able to get to the bottom of this...at some point I loose interest until the next summer when temps are over 110 ;)
 
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