Please help with A/C diagnosis.

[sellscottsell]

I have an A/C cooling problem and I’ve read almost all of the posts. There’s great information spread around this site and now I want to fix the problem myself!

The problem I have is that the A/C wasn’t getting cold last summer. I took my 1996 X 5.0 to a local mechanic who then promptly injected the system with dye ($45). After a week, he looked about my engine compartment and diagnosed that I had some leaks and he’d start by replacing my high pressure manifold line and see if he could chase down the leak. Well hell, I figured I could do that without the yellow glasses!

So I stopped by my local automotive shop, bought a recharge kit and a couple of cans of coolant. After I filled up the system, my X was blowing cold again and I was back in business for about 2 weeks. Since the problem started at the end of August, you guessed it, I just topped off every two weeks!

The only green dye leak that I noticed was directly under my Accumulator on the line. It wasn’t just the coupler, but the wet spot seemed to be traveling from further back towards the firewall.

Now I’m up against the wall and I need to fix my X properly. So the plan is to use my new orifice valve pulling tool and check for Black Death. If this is the case, I’ll start checking other components and flushing lines. I figure I can get a new compressor/clutch and a new accumulator and probably solve my troubles.

Question #1: Can I discharge the system by releasing the pressure from the high pressure valve near the left front of the vehicle? I pressed the stem in today and there was pressure that escaped.

Question #2: If I release all the pressure from this high pressure line, will it release the pressure at the orifice valve?

Question #3: If the valve is black, can I put it back in and then order my parts?

Question #4: Can I run the truck without a pressurized system? Or will this screw-up my compressor, provided it’s still good?

Since I use my truck to get to work (only 3 miles each way), I need to be able to check my orifice valve for black death and then button things up to get to work tomorrow.

Thanks in advance.

 

[Glacier991]

If one side of the system is depressurized, it will act to depressurize the entire system, including the orifice tube. Your description sounds much like a rusted out Accumulator, to find out pull the insulation off and check for rust. Either way it probably is going to need replacement. Betcha that's where your leak is. If the expansion valve (O Tube) is black just leave it out and close it up. Pull the wire going to the compressor clutch and tie it off safely somewhere. Lastly read the Useful Threads post on converting to 134a, and more importantly the associated post on how to recharge your system, it will help you. There is also a linked post about the accumulator rust out problem on Explorers there.Good luck.

 

[sellscottsell]

I think it's the Accumulator.

Thanks for weighing in Glacier. Last night, I removed and inspected the Accumulator. There was a et spot on the bottom of the accumulator and it had a lot of rust. To check the extent, I used the “hammer†method and whacked the bottom. It dented very easily and now certainly needs replacing! I couldn’t find pin holes, however I didn’t expect to since the system still carried pressure. So now I’ll replace the accumulator and have the system flushed and recharged.

Lastly, I tried to check my orifice valve. I think it’s probably easier to check your camshaft! The orifice valve is nowhere to be found when removing the accumulator. I’m finding that my membership to ALLDATADIY.COM is a total waste. I’ll buy the manual this time around!

Also, I inspected the lines to the accumulator and there was no evedence of corrosion or black specs. Probably this isn't a place to find a problem, however my compressor does seem to work when the system is charged, so I'll just give it a try with a new accumulator.

Thanks again.

 

[Glacier991]

The expansion valve is in the line from the condensor back to the evaporator. About mid way there is a spring lock fitting. Oil it, and use the spring lock tool to open it. You will usually need the removal tool (a free loaner from Autozone) to remove the valve from within the "bubble" in the line where it resides.

Follow the procedures outlined in the "Recharging your AC A to Z" thread and you should do fine. When you replace the accumulator, you should add 2 oz of refrigerant oil to it before you install it. Total 134 charge is 26 oz.

From your description you do not appear to have a stong liklihood of "black death" on your hands, just an accumulator leak.

 

[Bruce Rock]

I couldn’t find pin holes, however I didn’t expect to since the system still carried pressure. So now I’ll replace the accumulator and have the system flushed and recharged.

How did you look for them?

Did you pressurize the accumulator and use a soap solution or submurge in water?

Since you have added 134a to your system, you know how long it takes to empty a can through a large opening. Two week through a pin hole is not unexpected.

Before you recharge again, Please make sure you have identified and corrected at least one leak. It's the law.

http://www.epa.gov/ozone/title6/609/

 

[Bruce Rock]

Before you recharge again, Please make sure you have identified and corrected at least one leak. It's the law

Sorry! That's our State (Wisconsin) Law, EPA says it's alright.

 

[Glacier991]

Actually, since he has located dyed refrigerant leaks under a well known leak point, he has probably "identified" a leak. Since the system is discharged, he will need to properly evacuate it, if it holds a vacuum for 5 minutes, he has also probably "identified" (by fixing) a leak. I think he's covered <grin>.

 

[sellscottsell]

I'll tell you, the guys at the parts stores a useless. They think I'm crazy for diving into my A/C. And they're not very knowledgable about the parts they sell. I wish I could know so little about the equipment I sell!

Thank you by the way for the EPA data. I live in MA and I'm sure that if I blow off any chemicals, Ted Kennedy will have storm troopers hit my house in the name of enviromental safety. Additionally, John Kerry will probably try to turn me in just to get a metal! Perhaps he'll hold on to this metal!

I'll keep you posted on my progress.

 

[Glacier991]

The typical consumer auto parts store is poorly equipped for AC stuff., not the staff's fault. Real auto AC stores are staffed with great folks... but. When I forayed from my auto area into the home AC field, (needed to replace a compressor unit and redo the plumbing) I was met with a stony cold face.... I wasn't "one of them". They seemed to resent my attempt to use my knowledge. I prevailed, and saved my friend nearly $500, but learned that in AC they protect their turf. Never ran into it in Auto because I was "one of them". Fortunately for you you have Explorerforum, and you do not need their knowledge. Consumer or pro places. Thank Rick for making this place available.

Now, on the accumulator, matters not where you buy it. (other items don't have such safety in selection and I will NOT recommend buying everything at consumer places). YOUR problem, is going to be getting a vacccum pump. YOU need it. Buy a good gauge set. It will pay for itself in no time. If you have questions, come here.

ps. I am happy to hook anyone (well nearly anyone) up with my auto AC folks here, you will just have to pay shipping.