RTH: A/C system work on 91 FJ 80 (1 Viewer)

[ItWasntMe]

Hey everyone,
I have searched and researched and can't find exactly what I am looking for yet. I have a 1991 FJ 80 with 165k in Tucson, AZ. It's been like 112F at my house the past week. I'm getting kind of sick of not having A/C (it's my DD). When I bought the truck about a year ago, the compressor had no belt on it. After reading up on the subject last month, I replaced the idler pulley under the compressor as well as the belt. As expected, the clutch would not engage and so I took it into an Auto A/C specialist this morning (finally had the time to do so). He called me a few minutes ago and said I need the following:
-New compressor (clutch was "smoked," and he doesn't like to rebuild compressors this old)
-New receiver/dryer
-Flush condenser
-Expansion valve
-Evac/recharge system

He quoted me $1133. I have done some work on my LC myself, and consider myself a 3ish banana mechanic. Though I really haven't ever worked on an A/C system and haven't really had to rebuild a part like this before. I just wanted to see what your guys' opinions were on this. I have the FSM, and this stuff doesn't really seem that bad, but I also don't really have the time to devote more than a full day to the project. I also don't want to screw myself if I get into it, and it's more than I can handle. The system is still R-12. What do you guys think? Is this job out of my scope? Is this quoted price reasonable? Should I just bend over and pay the $1133?

BTW thank you for all the info on this forum. I am amazed that this is the first "please help me" post I've had to make.

 

[george_tlc]

Well, I just replaced compressor/expansion valve and dryer on a small GM car, R134 based. The compressor was 'dead'. Cost me about $450 to do it myself including oil and gas and the above components. I did already have gauges, a flush kit and a vacuum pump so didn't have to factor that 'cost' into the equation.

I'd suggest you cost out the 3 components you need to replace and then decide if buying (or borrowing if you know someone) the tools is worth the quoted $1133 (with presumably a reasonable warranty for the work).

Personally, 112F ambient temperature would be a big incentive to have someone else do the work and get cool air into my vehicle asap

cheers,
george.

 

[e9999]

Assuming that the compressor is indeed bad, and possibly aside from the expansion valve and condenser flushing (don't know why that's needed) the rest does not seem outlandish. You do indeed want to replace the dryer when recharging. Doesn't seem very cheap to me but HVAC guys are notoriously expensive. You could probably buy the parts much cheaper than he'll sell them to you.

None of this stuff is very difficult with a bit of reading, although not obvious that I could do it all in a day. Then again I'm slow. One problem though is that you can't just buy R12 OTC, you need a license. But you could do everything else but the recharge or use a replacement refrigerant like HotShot (I think, but that may also require a license, I don't know) to save costs. The good thing is that nothing you do should prevent you from driving the truck so it could be done in small increments.


correction: looks like I'm wrong above about needing a license to buy R12. Sorry.

 

[Roostre]

You could try just replacing the clutch. Not a terribly difficult job. If the system is still charged you might get lucky.
Then tackle the full job after it cools down.

 

[george_tlc]

Assuming that the compressor is indeed bad, and possibly aside from the expansion valve and condenser flushing (don't know why that's needed) the rest does not seem outlandish. You do indeed want to replace the dryer when recharging. Doesn't seem very cheap to me but HVAC guys are notoriously expensive. You could probably buy the parts much cheaper than he'll sell them to ...

IF the compressor has failed, then bits of stuff can be in the system, so replacing the expansion valve and flushing the system is a very wise investment and often required if you want any warranty on the replacement compressor.

All depends on what has really failed. Maybe it's just the clutch, maybe the compressor has seized... The HVAC guy will err on the safe side in calling out for new components since he's' the one that has to provide warranty on his work and not his pocket that is paying for parts.

The OP can determine if the clutch isn't engaging or if the compressor is seized. Given the belt was removed I'm assuming something is seized? Have a mate in oz and on our last trip bush the compressor on his 105 seized - lots of smoke from the belt with the clutch engaged. The clutch would engage/release ok, so I just unplugged power to his magnetic clutch and left the belt on until he got back to the city to have it repaired (for a big bunch of $$).

Applying 12V from the battery will allow the clutch to be tested for engagement (engine off etc). You can manually rotate the compressor without the belt to see if it is seized. Anyhow, a bunch of diagnostic steps to get an idea how bad or not things are before throwing $$ at it.

cheers,
george.

 

[BILT4ME]

I would replace the receiver/dryer, the expansion valve, and get a R134a conversion kit (O-rings and fitting adapters) and convert the unit to R134a. I would check to see what it takes to replace the clutch pack on the compressor. If it's not too hard, I would do that myself, and make sure I changed the oil in the compressor to a R134a compatible oil, then seal up the system and take the truck to a trusted AC service center and have them evacuate and recharge the system with R134a.

I did that on (2) GM vehicles I had and it was a lot less expensive than trying to find someone with R12 and trying to fix it.

 

[SUMMIT CRUISERS]

Tough call. If you have the time and want to save some $, do it yourself. I have found that Freeze 12 works great and is compatible with R12 systems. If you compressor is shot, do what George said. Not sure if the OEM clutch is available if your compressor is OK. I purchased a clutch about 6 years back for my son's 92 and it seemed very rare (very limited stock) to get through Dan @ American Toyota.

 

[ItWasntMe]

Thank you guys for the responses. After I posted this thread, I started looking for clutches, and it seems like they are pretty rare, if available at all. Crap. I talked to the dealer here, as well as a shop I trust, and they confirmed what I had found. Unfortunately, the A/C place is closed now, so I'll have to wait until tomorrow to find out more. I did pay them to charge the system with R-12 as part of an initial diagnosis, so maybe if I found a clutch I could swap it out and try to fire it up. It does look like I'll need a SST though.

The compressor spun just fine before I took it in to get looked at. Nothing happened (good or bad) when I turned on the A/C from the cab (except for the A/C light turning on), but I understand the clutch wouldn't engage without a charge. The A/C shop provides a 1 year warranty, so I can see why he would want to call for a whole new setup. Would the compressor's ability to spin mean it is not seized?

So without being able to talk to the shop until tomorrow, it seems like it could just be the clutch. Even so, I don't really know what my options are here. The parts guy at Precision Toyota said he can't get the clutch, and none of the aftermarket options he knows of will work here. The A/C shop said the problem could go deeper, and now I'm suspicious that he meant "let's do everything except the clutch and hope for the best."

I guess I'll keep looking for a clutch or an aftermarket option. Has anyone had any luck at a pick n pull with A/C components like this? It would suck to go pull a clutch from somewhere, only to find it's bad.

EDIT: I should add that the compressor itself is pretty easy to find. But it's always without the clutch.

 

[BILT4ME]

Buy a used compressor unit from @Akella or someone similar, replace the other parts mentioned above, and install and recharge with R134a. Check the 'Mud classifieds.

 

[Alleycats]

I also would suggest you convert to 134a which some say requires a different drier and the conversion nipple for the low side, then you can purchase refrigerant basicly anywhere. Call me a skeptic but I doubt your compressor is bad maybe you do have some leaks in the system though which need to be addressed.

 

[Landseer]

No personal experience but these guys seem to specialize in Land Cruiser AC and they're close to you, might wanna give them a call.
http://www.coolstreamac.com/home.html

 

[ItWasntMe]

No personal experience but these guys seem to specialize in Land Cruiser AC and they're close to you, might wanna give them a call.
http://www.coolstreamac.com/home.html

This looks really promising thanks! I'll call them as soon as they open tomorrow.

 

[Landseer]

The compressors on the 1FZ-FE engines appear the be the same part number as those on the 3FE so they should be interchangeable (has anyone tried this?). You can get a new Denso compressor with clutch for somewhere around $200.

 

[e9999]

mmm... all these calls about just replacing R12 with R134... is it just my imagination or would a system designed for R12 not show a significantly reduced performance with R134? If so, that hardly seems a great solution long-term if one is battling extreme temperatures.

 

[ItWasntMe]

mmm... all these calls about just replacing R12 with R134... is it just my imagination or would a system designed for R12 not show a significantly reduced performance with R134? If so, that hardly seems a great solution long-term if one is battling extreme temperatures.

This is what I've been thinking too. Eventually I'll be asking this rig to endure some climate extremes to say the least. I don't mean to start a big debate, but if I can get the system working reliably with R-12, I'd rather go that route from what I've gathered.

 

[ItWasntMe]

The compressors on the 1FZ-FE engines appear the be the same part number as those on the 3FE so they should be interchangeable (has anyone tried this?). You can get a new Denso compressor with clutch for somewhere around $200.

I didn't know this but thank you! I'm assuming the parts guy at the dealership would have known that though (at least I would hope).

 

[LS1FJ40]

R134 doesn't cool nearly as efficiently as R12. Having said that, what components are different between the 3FE and 1FZE AC units. If the compressor is the same would a person see a huge difference between the two.

The other thought is that R12 is virtually nonexistent anymore. They don't make "new" R12. They recycle it. Getting clean R12 is getting very expensive. I'm getting ready to jump in to the AC system on my 92 and just going to convert it to R134. Granted, I don't have the high heat that you have in Arizona but I have crazy humidity + 95 degrees. My bigger concern for fixing my AC is that the defrost doesn't work as well in the winter without a properly functioning AC.

I emailed coolstream about 6 months ago. They never emailed me back. Let me know what you hear from them.

 

[Landseer]

R134 doesn't cool nearly as efficiently as R12. Having said that, what components are different between the 3FE and 1FZE AC units. If the compressor is the same would a person see a huge difference between the two.

You could certainly see a difference in the same compressor with a different working fluid. R-12 and R-134a are so similar I don't think it makes a big deal.

I'd never considered the difference that converting from R-12 to R-134a could make but after a bit of research heres what I come up with:

First off, assuming the compressors are in fact identical, theres very little difference between the R-134a and R-12 AC systems. The condenser on the 134a models has ~12% more area but is .7cm thinner than the R-12 condenser, so pretty much the same. The expansion valves appear to be different and they are probably tailored to work optimally with their respective refrigerant. If you did switch to 134a its probably worth trying to switch to the 134a expansion valve (Looking at pictures the valves appear to have the same dimensions and are probably interchangeable?)

The real question then is how different is R-134a from R-12. Google brings up a bunch of conflicting sites on the efficiency of R-12 vs. R-134a, some claim R-12 is better others say R-134a can be better. Looking at the thermodynamic properties of R-12 vs. R-134a the 134a has a higher (~25% higher) enthalpy of vaporization (it takes more energy to boil the liquid and the vapor will absorb more energy when it condenses). Therefore if you are moving the same mass of 134a through the system and completely boiling/condensing it on each cycle the R-134a will remove more heat, however the 134a has a higher boiling point (by 3.5 degrees C) and therefore will likely be at slightly higher pressure. This agrees with this website: http://griffiths.com/ac-system-help-introduction/r134a-vs-r12/.
Quick summary from above website:
"Pound for pound R134a is a more efficient refrigerant than R12, however it runs at higher pressures in some aspects and therefore requires more effective condensing. Whether R134a performs as well as R12 in any given a/c system depends upon system components and the amount of R134a used."

My take away from all of this is that switching to R-134a will likely not result in any noticeable difference in AC performance. Its worth noting that essentially every vehicle made in the last 20 years runs R-134a as do many refrigerators and home AC systems.

 

[Alleycats]

And if you run 134a you can charge it yourself super easy whenever you want for peanuts.

 

[Hornd]

I have done this job so let me give some insight.
Order up Denso (OEM) components on Rock using the 5% coupon to cover shipping.
Replace a component a night. Take your time and don't bust anything, or you will have a real headache finding replacements.
I would convert to 134A (they both work, and that's all you really need to know) 134A is about 10X easier to get. Put a small amount of oil with dye in each component. Dye makes finding leaks in future much easier.
Change the expansion valve (clean Evap Core) , change the Accumulator/Dryer and reassemble all fitting using Mineral Oil.
I did the condenser one night after work, the expansion valve one night, and Accumulator Dryer on 3rd night.

Talk to the shop that you are going to have fill/vacuum. Ask them how they test for leaks and how long they check. Correct procedure is to pull under vacuum, then let sit for an hour and see if gauges moves. The vacuum boils off the moisture and fill into airless system. This cost me $70, which I consider negligible if you don't have gauges and vacuum pump. The oil in these systems becomes acidic when exposed to moisture. Do it right the 1st time and I can speak from experience that all 3 of my Toys with close to 200K have working AC.
Buy yourself some good beer for the end of each night realizing you have saved over $1000, plus you learn a skill which lasts for a lifetime.