OK I have since figured out that my syncro has the larger fan setup,
and my Bently (should have checked first) lists the SD709 as a
replacement for the SD510.

But I am still wondering about the 253 260 403 two fin section
condensor (versus the 255 272 413A condensor which is single fins).
Are these interchangable? How do I tell which one I have?

This also brings up a third point the reciever/dryer for the SD709 is
253260633E and for the SD510 its 253260633D. Though I know I have to
change the reciever dryer when I change over my AC system I'm not sure
which one to get. Bentley has no advice on the matter.

Hot and Bothered
Chris

On 6/17/05, Christopher Gronski <gronski@gmail.com> wrote:
> I drive an 86 syncro westy and I want to add front AC to my existing
> rear AC. My current (seized and leaking) compressor is a SD510.
> 
> Bus Depot lists the SD508, the SD510, and SD709 for the '86 model
> year, all are the same price. Am I correct in assuming that the 5
> series compressors are 5 cylinder and the 7 series are 7 cylinder
> (hence the 7 series would be more powerful. I assume I would just have
> to change the fittings. Is there another difference? Are they
> interchangable?
> 
> Since I am adding the BEHR unit up front I thought it might be prudent
> to upgrade to the SD709 along with the upgraded 253 260 403 two fin
> section condensor (versus the 255 272 413A condensor which is single
> fins). Again I am wondering if the condensor is interchangable.
> 
> Lastly is the radiator fan. Volks cafe lists a fan assembly
> 251.959.455M at $445.00
> which seems a little steep. Would I have to buy this whole setup (plus
> the condensor) if I wanted to upgrade the fan?
> 
> Any advice would be appreciated...
>