Evaporator

[nobby]

Yes the part should be available from Honda but it could have a lead time on it.

when I needed the part it was very expensive from HUK and I don't think it's repairable... I was unable to get anyone here.

i took a chance on a used one and it turned out to be fine and this was one of the big jobs on my car at that time ... Lots of mini projects with our NSX

[Kaz-kzukNA1]

If it's for the RHD R134a spec, then the OEM evaporator is still available in Japan. I bought it recently.
You may struggle ordering it through HUK dealers as it’s shown as 'unavailable'.

I think the one for the R12 spec is no longer manufactured.

Not sure about the LHD but with the RHD, the size of evaporator is the same between R12 and R134a so it will fit inside that big white plastic body of the heater unit regardless of whether your NSX left the factory with R12 or R134a a/c system.
Also, for some reason, NSX is using the same fitting thread spec between R12 and R134a evaporator that it's a direct replacement. Normally, the fitting size/thread is different between the two gas.

It's the heater core sitting behind the evaporator that you need to be careful but I'll leave it for now as it's off topic.


There were several aftermarket evaporators for LHD at very reasonable price but haven't seen one for the RHD model.

If the crack is somewhere accessible without damaging the fins, you could weld it but quite often, the part of the evaporator core has expanded and then cracked so the crack could be somewhere at the hidden place and not easy to repair.


Kaz

[marknsx]

Hi Kaz
I have been offered a second hand evaporator. No idea of its history and if it leaks or not. We need a way of telling without connecting and before it leaves the supplier in Holland. Any thoughts?
What is the cost of the new one for my RHD car?
Thanks

[marknsx]

You are right my Honda dealer was told that Japan have no new RHD evaporators.
Thanks

[Kaz-kzukNA1]

The compressor oil circulates throughout the system via a/c gas so if the gas is leaking from the evaporator, you will see sticky black wet marking around the cracked area.
You would imagine you would see the crack at the high pressure side but for some reason, most of the time, it happens at the low pressure side.
Typically, you will see the crack at the welding point marked with yellow arrow.
Also, the area marked in yellow could expand massively and cause crack somewhere.

If using an used one, you never know how it was stored and thus, you must flush it first.
You will be forced to remove the expansion valve as you can't pass through it without using the professional a/c flushing station but you should replace it with a new one any way so just disconnect it.
Once expansion valve is removed, be creative to leak test the evaporator.
Just make sure you know what you are doing as depending on the chemical used with your a/c parts, it could catch fire when it meets the compressed air so be careful.

I haven’t checked the stock level of RHD evaporator in Japan recently but there were plenty available in April…..


Kaz

[Formula 91]

HI Kaz, Thanks for the excellent information regarding the evaporator . I have a been informed that I have a leak leak in my system . Is it easy to see if the evaporator is leaking and if so is the new style evaporator a direct fit or does it need to be modified to fit a 1991 NSX .

[goldnsx]

The R134a evap is a direct fit for the R12 one. Regarding the labor to replace it I'd pull the trigger and buy a new one. Then you have the R134a valve too.

[Kaz-kzukNA1]

As in my post #12, I can confirm that the RHD R134a evaporator is a direct swap even for the heater unit that left the factory with R12 system so good to know it’s the same for LHD model as well, @goldnsx.
Somewhere on Prime, I read someone telling that it was not the case so looks like another wrong information there like the info on 02+ NSX-R brake calliper size.

Formula 91, I don’t know the spec of your NSX (RHD/LHD, R12/R134a, etc) but together with the info from goldnsx, the evaporator would be a direct swap between R12/R134a for both the RHD and LHD models.
Just remember that the evaporator is a sided parts (RHD or LHD) so get the correct spec for your NSX.

If your NSX is 91, very likely to be R12 or retro fit to R134a.
If you are still running the R12 spec compressor, replace it with the R134a one at the same time when replacing the evaporator.
At the time of retro fit, the compressor should be replaced as well because most of the time, the original R12 compressor would fail in a few years after the R134a conversion was carried out.


Kaz

[Pride]

What a lot of info there is for what seems such a simple swap out.

[Kaz-kzukNA1]

It’s open forum.
It’s upto each individual to decide how far one wants to share the info.
It’s also upto each user to decide whether to read the post or not.
If you don’t like it, don’t read.

Kaz