Air conditioning evaporator questions

[tw2]

I know most people wouldn't bother but I really want to get my A/C working. It has a leaking evaporator under the dash so I ideally need a new one. New (older style R12) ones are unavailable from Toyota or anywhere else. New 94+ R134 are probably available from aftermarket sources. These are incompatible with the older R12 lines on my car.

So I can get a new style evaporator core but would need to find a gen 3 wrecked that I can cut the fittings off for the newer style and have them braised on my hardlines. Or I try and find a wrecked 90-93 (much easier) for a non-leaking evaporator. I don't believe the evaporator is a common failure point, maybe I would get lucky with a second hand core. What should I do?

There are brand new evaporators on ebay for LHD cars but I don't know if they are the same, mirror images, flipped around or 100% different than RHD. Anyone have any pictures of our RHD ones?

[GDII]

JDM/EURO cars used the same part number but the USDM did not.

http://jp-carparts.com/toyota/partlist. ... 3&fig=8714
I'm not sure if this is any help to compare to the USDM ones yo have found. Looks the same but as it will be backwards it may not fit.

[tw2]

Thanks for the reply. Amayama have it for NZ$427 + 60 shipping from Japan so that is a good back up option. Externally as far as I can tell the JDM and USDM are the same. I found this post on a Canadian forum since they are able to import JDM cars from Japan reasonably easily and he had a JDM car:

http://bcmr2.com/forums/viewtopic.php?f=3&t=10617

The evaporator core I got from Tech Choice Parts (part number 88501-17030; cost was $66.18 plus $31.25 USPS shipping) is nearly exactly the same as the JDM part (88501-17040). The only discernible difference is that the US part is about 1/4" less tall (easily shimmed up). The in/outlet offset I was concerned about is a non-issue (offsets are exactly the same on the same side).

I think 88501-17030 is the USDM R12 1991-1993 model.
- 88501-17040 is JDM R12 1989-1993 model.
- 88501-17050 is JDM R134 1994-1998 model.
- 88501-17060 is USDM R134 1994-1998 model.

I found a 17030 OEM denso unit on eBay so I might take a chance on that to hopefully save $400. There are cheaper ones but I rather the denso for not too much more.

[tw2]

So finally had my evaporator and condenser arrive. The condenser is the same part number for all markets so shouldn't be an issue. I haven't taken the old one out yet but it looks the same from what I can tell.

Evaporator is indeed a little bit different. The external dimensions are 100% identical. I carefully measured the height, width and length. The difference is solely due to the placement of the outlets. They are one "bump" over. This means the pipes will stick through the firewall approximately 1cm further. If the 3D mapping in my head is correct then it will still align perfectly with the hole in the firewall. Our AC lines are straight on fitment after going through the firewall. Looking at my USDM BGB it looks like one of theirs is a right angle connection requiring a slightly different fitment.

[tw2]

I just can't work out why it was leaking.

[tw2]

Right so I found one more issue apart from the irrelevant change to the pipe length. The thermal expansion valve was designed to only fit on one way. The two O-ring boss' are very slightly different. It bolts up both ways, it might even seal the wrong way round but it doesn't sit 100% flush (I can see it sits a fraction of a mm out on one side). The guy above in Canada obviously didn't look very hard when he installed it. My A/C guy is looking for a TX valve that will work so hopefully not all is lost. It was always going to be a gamble. Otherwise I might have to get a RHD model from Japan

[tw2]

Small update for anyone who is interested. The evaporator is apparently made with thin pressed metal with expoxy and stuck in a furnace so my local radiator specialist said there is no way to cut and weld the old fitting onto the new evaporator or to cut the flange off and braise it back on 180 degrees. There doesn't seem to be an appropriate TX valve to reverse the situation either and even if there was it would require the lines to be switched over as well which would be a custom job.

The good news is that the TX valve appears to be perfectly symmetrical and the hoses from the evaporator are the exact same size and use the same o-rings. Unlike the condenser and every other part of the A/C system it also doesn't matter which way the fluid travels through the evaporator. So I have taken the TX valve to the machine shop and they will enlarge the smaller hole in the TXV to allow the larger lip of the evaporator to sit flush. If this actually works then it is an ideal solution for us RHD aficionados.

[tw2]

The machine shop was able to enlarge the hole to fit over the lip of the evaporator. They did an awesome job and charged $50. The next issue was when fitting the evaporator to the plastic container, the pipes fit in an indent in the top of the housing. I knew the pipes were one notch further down the evaporator, LHD vs RHD versions but I didn't realise this specific indent was there. It fits, just need to shave 1-2mm from the inside and remove a small piece of foam. The thermal expansion valve clears without issue.

So I have fully functional A/C using the LHD denso evaporator from the U.S. and 4 degrees air temp at the vents. Fully flushed lines, compressor emptied and PAG oil used, vacuumed for 30 mins, rest of the oil added with the refrigerant (only 50mL fits in the compressor), all seals replaced, new drier. Seal locations are:

- Evaporator and thermal expansion valve (TXV) there are 4, two on either side of the TXV
- Compressor 2
- Condenser 2
- Drier 2
- There are fittings right under the compressor at the bottom of the firewall, I think just one seal but it will be obvious.
- Also fittings at the very front before the lines go up into the frunk, again might be just one but could be two, the A/C tech did those ones.
- At the charge fittings there are 2-3 more. Use the green seals which work with R134a.

You must replace all seals if doing a R12 to R134a retrofit, it will leak otherwise over time. Definitely needs a thorough flush and vacuum. In my mind there is almost never a situation that is simply requiring a recharge, it has leaked out somewhere. Also since R12 is illegal to sell, an overhaul is the only option for the early cars.

[pbaron]

Thanks Thomas, where did you get your new condensor from and how much was it?

Cheers
Pierre

[tw2]

Ebay https://www.ebay.com/itm/A-C-Condenser- ... 2921681043

Approximately NZ$200. It was the best deal for a highly rated seller with free shipping in the USA (to youshop).

Also apparently R12 and R134 fittings are not compatible so using R12 components with R134 is easier than replacing all the lines to use the later revisions with the 94+ cars.

[pbaron]

Was the youshop shipping much less than the 145 global shipping estimate on ebay?

I am looking to reinstate the aircon on mine.

Cheers

Ebay https://www.ebay.com/itm/A-C-Condenser- ... 2921681043

Approximately NZ$200. It was the best deal for a highly rated seller with free shipping in the USA (to youshop).

[tw2]

NZ$79 was the youshop price for the condenser.
NZ$68 for the evaporator shipping.