A/C system

[Buzo]

I spent last night reading all the posts in the forum about the R12 to 134a conversion (most of them dated from 2005), just to find out this morning the previous owner had already done that in my car, and I know it because the port fittings already matched the 134a charging hoses.

So proceeded installing the missing A/C belt (its a nippon denso compressor) and then with one can of 134a+leak detector+oil+leak sealing.

I first did what the guys in the forum said about keeping the can straight up for vapor charging, but nothing happened in about 5 minutes.
As soon as I started turning the can 90 degrees and back (per the instructions in the can), the A/C clutch engaged itself.
It stayed engaged for maybe 5 minutes more and then it started making the normal on/off cycles. Yeah, I keept moving the can from time to time.

I know our friends in Michigan are still getting some sprint snow, but here in El Paso area we already need some A/C in the evenings.

I'm also glad the A/C boost solenoid is not controlled by the control box since I removed it, so the engine keeps the good RPMs with the added load.

I used what you can get from autozone, a charging hose with a gauge with blue, green and red colors indicating where the pointing arrow must be, according to the ambient temp.

I'm still surprised how easy it was, hope it lasts...

[Dr_Snooz]

Nice work. With straight 134, you keep the can upright. If it doesn't fill, dip it in a bucket of hot water. Just don't let the head pressure spike too high. For the stop leak stuff, you do need to rock the can from side to side.

[forrest89sei]

Congrats!

Your lucky to have a car with the R134A Friendly Nippondenso Compressor :D


Stay Cool :P

[Pnem3]

I would check the instructions on the can as to how to hold it. Since it is not pure R134A, you might have to hold it upside down. If you charge as a vapor then the oil, leak seal, and dye you spoke of might be left in the can after all of the gas (R134A) has boiled off. Said another way, the R134A is meant to push the other stuff out of the can.

Also, I'm not a fan of the one line hoses that they sell for charging. It is best done with a set of manifold gauges. It is important to see what the high side pressure is because if the high side is too high for some reason (poor condenser, poor fans, over-charging) then the whole system could be damaged and that costs way more than the investment in a set of gauges to repair. Sometimes, you can borrow or rent the gauges and it is worth it.

One important thing to be wary of is whether the conversion was done properly, with a complete system flush and oil change. You can search on the net for "AC black death kit" to see what could happen if it wasn't done right.

You should find plenty of good AC advice on these boards and we will be here to advise if needed.

Good Luck, and stay cool.

[Xaisk]

Last year I rebuilt mine at home. Flushed it, replaced all the O-rings and gaskets, and had a new compressor to boot.

Be CAREFUL ever even considering taking it to a shop because they will #(@)# #@() up. I took it in to a A/C shop and told them specifically to put 70w oil in. He said he would. I came back an hour later and he told me that he put 140w oil in and that it was "better for our cars" come to find out my A/C dont work no more. Worked for about a month but it put so much load on the motor... about 250 RPM drop when turning the compressor on. It leaked all the R134A out somewhere so I also take it it destroyed some of the seals too.

Now I get to do the same job again... NEVER GO TO A SHOP! DO IT YOURSELF!

[Buzo]

Everything was working fine, but one day I found the red leak detector in the floor, right under the compressor pulley. looking at the manual there is one shaft seal and a special tool to replace it.

Does anybody know the shaft seal part number for the nippon-denso compressor? And also where to get the special removal tool?

Thanks in advance.

[DBMaster]

To access the shaft seal you have to remove the clutch assembly. If it were me, I would replace the compressor. Of course, I did that just last year. My problem was bigger than the seal. The clutch shorted, seized, and melted its power lead. I bought a brand new Denso compressor on Rock Auto for $300.

[Buzo]

To access the shaft seal you have to remove the clutch assembly. If it were me, I would replace the compressor. Of course, I did that just last year. My problem was bigger than the seal. The clutch shorted, seized, and melted its power lead. I bought a brand new Denso compressor on Rock Auto for $300.

Supposedly you don't need o remove the clutch assembly. There is a C-ring and then need this special tool to pull the saft seal. I searched in the Autozone website but there are hundreds of types of seals.
If nowbody has bought this piece before that can tell me the autozone PN, I will remove compressor and take it to the local A/C shop just to get it replaced.

[DBMaster]

That'll teach me! I was commenting based upon my knowledge of the compressor that came on my car - a Keihin. I used a kit made by Honda back in 1999 to replace it with a Denso. I again had to replace the compressor last year. So, for me it seems like 10-11 years is the device's life span. If your compressor is that old I don't know if it's worth the trouble of trying to repair it like that. But, everybody's financial situation is different. I can't afford to have my car down and driving in the summer around here without A/C is unacceptable to me. I have saved more than enough money over the years by not having car payments that I accept the occasional high dollar repair.

[Buzo]

It depends on the failure mode, if there was noise on the compressor I could think of a bad bearing, then a complete unit replacement is the way to go. But everything runs smoot, so i'll try changing the seal first.

I'm glad I can still run with the windows open, the >100 F days are at 3 to 4 weeks ahead. So I better hurry up in this repair.