klr10

Following on from the new accelerometer thread, John at JDSPorsche has mentioned there is a possibility of a re-engineered servo motor for our ageing heating systems if enough interest is shown. This is the thread to register your interest.

I would definitely be interested in a more elegant/reliable solution.

f3nr15

There's been a recent relevant discussion in the 993 forum -

Rennlist Forums - Damaged HVAC servos could be history

FYI.

John Speake

OK, I'll see what's in that thread.....

Rocket Rob

John Speake

So according to the 993 thread, there is already a rebuilder who has invested in a refurb solution for about
249 Euros/ $325 each. But people think this is too high a price ?

So the question is - what is considered a "sensible" rebuilt cost ?

jimq

I dont think the 993 ones fit the 964. Theirs are in the cabin on each kick panel while the 964 has them on the firewall.

Zingari

Aren't they the same design inside as it is really the circuit board that's needed with the metal prongs that provide the rheostat function to move the levers/flap.

I'm new to 964 but surely we have the same for the upper/lower dash flaps under the cover in front of the bulkhead? Cant check as my car is away for work.

The best solution would be to remanufacture the PCB - something that Chinese expertise could do very well? If it;s just the PCB and they fit all servos then £50 is reasonable given that full (secondhand) working units can be sourced for ~£75 (albeit infrequently)

f3nr15

The 964 and 993 each have the 5 HVAC servos. They differ between the two cars in their location and in the types of actuating arms that are fitted to the servo units, but the servo units themselves are actually the same, and are all stamped with the same 964 part number.

Realistically, ALL these servos are likely to begin to fail within the next 5-10 years.

The servos are selling for the $400-500 mark for new replacements.

It'd be nice to have a refurb service available for the sub-$200-$250 mark.

John Speake

It seems to me that the existing solution/refurb available is not that far away from your target price.

As the quantities rise, and his tooling costs are recovered, I would think he could have the oportunity more towards your target price (hopefully lower).

Partisan

Hy guys,

my name is Michael, Iam the person who developed the refurb solution.

The 964 and the 993 servos for footwell, defrost and fresh air are the same. For the cold/hot mixing chamber flaps there are different types used. 964 uses a 130deg with the metal lever, 964 uses a 60deg type with the black 'star' instead.

I will think about the pricings for you guys in the USA. I also offer a very good repair / rebuilt service for the CCU. Maybe I will make a bundle price for all five servos and the CCU.

I think everybody will be happy.
Ill be back tomorrow, this day was very busy.

So long,

Michael

Partisan

Of course also for you guys in GB and in Australia and where ever...

Michael

A8KED

I have replaced each of my mixing chamber servo valves twice and have used the repair/disasembly/cleaning tips as outlined in Adian's book. But they continue to fail every few months. I now keep a spare valve at the ready in my garage. I'd be interested in a GOOD quality replacement unit at around $200.US.
Kevin

alexjc4

This may be crazy but how about using modern stepper motors and hooking them up to a simpler replacement for the ccu, i'm sure there'll be control logic out there for hvac sustems that could be repurposed for a cheap microprocessor. You might need to get creative with brackets and user interace but at least that way use lose all the old junk. I struggle with the idea of $1000 on servos to keep everything running.

Sire

keep us informed.

hamah

Sooner or later every single one of these cars (where a functioning HVAC system is required) will need these servos attended to. It's only a matter of time. So, yeah, I'm interested in a reasonably priced alternative or restoration.