Any auto parts store will sell an Oring kit specifically for that car and it will have every one you need .
Automotive AC troubleshooting 101 - help me get started?
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Very interesting. I see now that there is a Nissan specific kit I should have ordered. Continue to learn.
I think I am going to order the OEM ones since I don't know what I am doing - one less variable. Still I might order the Nissan kit also - so I can compare them both for my education. I really don't know much about sizing O-rings.
If I may ask, since you do this as a side job, what vacuum pump and gauge set do you use?
Rockauto lists this Four Seasons 24661 as the o-ring for the high pressure hose for 46 cents. Also, this Four Seasons 24684 as the o-ring for the low pressure hose for 42 cents. Sure seems more reasonable than $8 each from NISSAN...assuming you are ordering other items from Rockauto cover the shipping charge.
I have an actual ac machine. It's an rhs980. I also have an inexpensive scale I can use if needed.
As for matching orings I just look and can I.D. them. I'm also very nearsighted and can see up close and small details well .
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Thanks! I didn't see anything coming up in RA when I looked except the kits, which I previously had assumed were generic.
Unfortunately - or maybe fortunately - I already paid Z1 $45 to ship me 4 o-rings. Given I don't know what I am doing $45 to remove a variable might be well worth it. I may still order these so I can compare.
The Four Seasons ones list the interchange numbers which I was able to google.
The large one is not at all like what I put in. Its clearly 21/32, so about 1/32 tighter than the groove it goes around.
The second one is in fact 7/16 - but its thinner than the one I put in. I hope I did not hurt anything stuffing the heavier one in - besides it.
So I have learned the O-ring needs to be a reasonable amount smaller than the groove it goes around, and my eyesight isn't great at judging these sizes.
Initially, I also did not find the individual o-rings listed in the RA online catalog. So I resorted to an alternate method by looking up the high and low pressure replacement hoses sold by RA. The Four Seasons hose listings provided the specifications, including the corresponding o-ring part numbers. I then searched for both Four Seasons o-ring part numbers in the RA catalog.
You won't regret your decision if you can fix the Xterra's A/C for less than $100 in parts (not counting the new tools). Who knows? Maybe the NISSAN hoses use a different o-ring than the Four Season aftermarket hoses.
Yes, none of this is about the cost. The education portion is invaluable.
I will have both hoses off again shortly - when the proper seals arrive. Should I add some UV dye? If so, how much and what kind? Would this be good?
The A/C Pro UV dye you posted will be perfect for the NISSAN. I'd suggest adding a quarter ounce (i.e., 1/4 the bottle) to the system. Note that the bottom of the package says "4 applications per bottle".
I so want to thank all of you that have helped me. You are so AWESOME. I would still be trying to find the Schrader valve to clamp to if not for all of you. You are all very generous people.
So maybe I'll do more write up later, but as of last night, it has pressure, its blowing cold air, and my leak detector on its most sensitive setting detects no leaks. I suppose time will tell, but it looks promising.
Of course, I still have more questions.
The manual states the capacity should be 0.70 KG +/- 0.05KG, so 700g +/- 50g. Thats 24.64 +/- 1.76 ounces for those that prefer.
I weighed the little cans before and after on a very accurate scale and I dispenced 665g of refrigerant. Now of course there was some gone from the purge and some in the lines when disconnected, so my guess is I am very close to the bottom end of that 650g range. So I think I should put a little more in?
So what's the best way to add now? Should I just use my self sealing can tap instead, close the quick couplers at the Schrader valves, purge all the lines and put a little in?
Second question - how do these pressures look? This is at idle - was a very hot day. I didn't have a helper to rev up the engine.
So maybe I'll do more write up later, but as of last night, it has pressure, its blowing cold air, and my leak detector on its most sensitive setting detects no leaks. I suppose time will tell, but it looks promising.
Of course, I still have more questions.
The manual states the capacity should be 0.70 KG +/- 0.05KG, so 700g +/- 50g. Thats 24.64 +/- 1.76 ounces for those that prefer.
I weighed the little cans before and after on a very accurate scale and I dispenced 665g of refrigerant. Now of course there was some gone from the purge and some in the lines when disconnected, so my guess is I am very close to the bottom end of that 650g range. So I think I should put a little more in?
So what's the best way to add now? Should I just use my self sealing can tap instead, close the quick couplers at the Schrader valves, purge all the lines and put a little in?
Second question - how do these pressures look? This is at idle - was a very hot day. I didn't have a helper to rev up the engine.
What's the ambient temp?
Glad to hear that you have achieved success with the Xterra A/C repair. The first attempt at A/C work has a very steep learning curve, but it is coasting downhill from here.
Without knowing your exact climate conditions, your readings look pretty good to me based upon the chart below. If you look closely, you may be nearing a slightly overcharged condition. If it is cooling well now, I will advise you to just leave it alone as I have seldom been able to charge 100% capacity per the manufacturer's specs.
Without knowing your exact climate conditions, your readings look pretty good to me based upon the chart below. If you look closely, you may be nearing a slightly overcharged condition. If it is cooling well now, I will advise you to just leave it alone as I have seldom been able to charge 100% capacity per the manufacturer's specs.
Weather service tells me that at that time it was 91 degrees with 63% humidity.
If you rev it a little does the low side drop closer to 40?
I will check tonight.
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You should be checking at between 1,500 and 2,000 RPM.
The high side is a little high for idle, but there's no fresh air flowing through the condenser like it would be driving down the road.
You can put an additional fan blowing at the grill to better simulate that while sitting.
Make sure the condenser fins are clear, (I'd bet that's already done) and the condenser fan(s) are working well.
Also - if you did indeed install dye you should sweep the area with your UV light after running it.
The high side is a little high for idle, but there's no fresh air flowing through the condenser like it would be driving down the road.
You can put an additional fan blowing at the grill to better simulate that while sitting.
Make sure the condenser fins are clear, (I'd bet that's already done) and the condenser fan(s) are working well.
Also - if you did indeed install dye you should sweep the area with your UV light after running it.
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If it comes down fast it means the compressor is tired. It should be closer to 30-40 psi. Or the guage is bad.
OK, was going to plug in, but decided to ask some questions first.
If it comes down fast the compressor is bad. Does that mean I should pre-emptively change it. No doubt its tired - has 412,000 miles and is 17 years old.
Is there a scenario I should add refrigerant?
Anything else I should know?
I sort of wanna be ready so I don't have to plug in a third time, since you release a little each time.
Thanks!
If you are satisfied with it leave it alone. The low side pressure coordinates with how cool the air out of the vents is. Me personally would not like 58F air out of the vents assuming that the gauge is correct.
I do not recommend adding refrigerant to a partially filled system. You have no idea how much to add and even going by pressures with r 134a can be tricky
Short drive around the neighborhood - fresh air mode - in 2nd gear, so 25mph, just under 2000 RPM, it held pretty good at 51 degrees.
Let off the throttle and it would creep up to 53 ish.
91 degrees, 61% humidity outside according to weather service.
Its plenty good enough for this old rig, unless there is something else I should do?
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