As far as I know there is no difference in the AC systems between 84
and 85. That said, if you are installing an AC unit in a van that did
not originally have AC there are some system upgrades you may want to
do "while you're at it". Have a look at this post I made last
summer...

Chris

> I spent a bit of time investigating this.
>
> VW changed the AC in our vans around 1986 or 1987. From what I can
> tell '86 2WD do not have the change, but '86 syncros have a partial
> upgrade (fan, condesnor, compressor), '87 and newer had even more
> (this coincided with the switch to the grey interior).
>
> In terms of the condensor, with the '86 syncro they moved from
> 255272413A that has two sections of fins (with none behind the
> separation of lower and upper grilles) to 253260403 that basically
> covers the whole rad.
>
> Compressors were upgraded around '86 as well some got the SD510 and
> some the SD709. Both were an improvement over the SD508. The first
> number refers to pistons, the second to total displacement. In this
> case the SD510 is about 11% more powerful than the SD709 but the SD709
> is aparently much quieter and saps less power (and it is13% more
> powerful than the SD508).
>
> Both are available from Busdepot. I had the more powerful SD510 in my
> syncro but its dead now and in the interest of future availability
> (Sanden is no longer producing the SD510 - pity it is 25% more
> powerful than the SD508 of earlier vans) I will be replacing it with
> an SD709. The procedure is detailed in Bentley 87.16 and requires two
> specialized refrigerant lines: 253260708E and 253260716A and two each
> of these o-rings: 803260749B & 431260749.
>
> Also around '86 fans were also upgraded from 251959455G to the more
> powerful 251959455M.
>
> The '87 and up grey interior vans got the extended AC ducting off the
> rear AC as well as a larger evaporator and more powerful evaporator
> fans.
>
> So, it is possible that the other vanaagon owners who are reporting
> 50F at the vents have newer vans with the VW AC upgrades noted above.
> I was lucky enough to already have the upgraded condensor and fan. I
> am changing out the compressor and plumbing in a BEHR aftermarket AC
> unit that has a second evaporator and fans up front. I am hoping to
> catch a cold this summer...
>
> Chris

On 12/7/05, Michael Diehr <md03@xochi.com> wrote:
> What are the differences between the 84 and 85 westy?
> How much work is it to swap the AC system from an 85 westy into a non-
> AC 84 westy?   Any idea how many hours of labor?
>