1993 Porsche 964 C2

hot66 · Post by **hot66** » Sat Oct 19, 2019 8:57 am

Another year and more memories added

( incase anyone is interested

.. the coat of arms is for the city of Dusseldorf )

hot66 · Post by **hot66** » Tue Oct 22, 2019 12:35 pm

Not been 100% problem free year though ....So, one problem that did show itself on my trip to the dolomites was the clutch pedal roll pin. Beginning of the year , to solve a problem of the clutch pedal hanging , we replaced the bearings in the pedal box and thus installed a new genuine Porsche roll pin. This pin worked itself out which became apparent with the gear change becoming notchy ( due to the clutch not fully disengaging) and ultimately full loss of the clutch pedal. Luckily pretty easy to sort when out on the road if you know what to look for ( I’ve had previous with the roll pin failing on my 1973 car so it was the first place for me to look when I lost the clutch ) . My roadside fix got me home with no probs, but when I checked it again the roll pin had started to walk. Fix no2 was a new roll pin and to use lock wire to try and hold it in place ... trip to spa and back and again the pin had walked

My theory is the clutch pedal has been travelling too far ( the pedal stop was bent ) and the master cylinder has been bottoming out and the pedal been pushed beyond its travel and putting strain on the pin and possibly elongating the holes in the linkage ??
Bit more research and it seems Porsche identified this area as a problem so for the 993 ( and I think the 965) this was redesigned with a splined fitting .

The option of replacing the whole pedal assembly with a 993 one is on the cards ... but before that I’m going to replace the clutch pedal, clutch link and the roll pins along with a new pedal stop + will loctite and lock wire it... and hopefully with all parts being new it should hold together like the original did for the first 25 years

Will know if this all works as we go through the next 6-8 months of driving

yoda · Post by **yoda** » Tue Oct 22, 2019 2:24 pm

Great to see the car getting so much use James - lovely car.

jwhillracer · Post by **jwhillracer** » Tue Oct 22, 2019 8:34 pm

I know that it's not the same assembly, but I have had similar problems with both our 72"S" based Hillclimb car and our 914/6. The roll pins wore and broke up, and replacements didn't last as long because the roll pins are hard enough to deform the cast pedal arm and steel operating shaft. My local racing car manufacturer solved the problem on our 911 by reaming the 6mm hole through both to take a 1/4" NAS bolt and K nut - absolutely solid! When the 914/6 clutch pedal started to play up I bought a 1/4" reamer and did the job in place myself, without having to remove the pedal box. Once again, problem solved.
If you think that might work in your case, I'll happily lend you the reamer to do it.
Cheers,
JW

hot66 · Post by **hot66** » Tue Mar 17, 2020 12:12 pm

hot66 · Post by **hot66** » Sun Aug 16, 2020 9:45 am

Not much to update as I haven’t really used the 964 much recently with lockdown etc

Going back a few posts, you’ll see I was talking about a problem I’d been having regarding a clutch pedal that would sometimes hang and not return the last 1” without a nudge from my foot . Things like this for me are really distracting when driving quick . So pre the alps trip we got the pedal assy stripped and all bushes replaced ( the bushes needed doing as it turned out ) which helped but that also led onto the clutch pin problem which also led onto the clutch pedal itself being replaced as the pin hole at enlarged due to the pedal being pushed beyond the travel of the clutch master cylinder. It wasn’t perfect and as we entered 2020 the clutch hanging got worse again.

So at service time, we replaced the clutch master cylinder . Old one had play in the shaft and wasn’t quite smooth so needed replacing anyway really... result, no difference.

I could feel the hanging clutch got worse as the car got heat into it ... which pointed towards the gearbox end of things as there is a pressure hose and slave cylinder located there and things get warm from engine heat etc . So both clutch slave cylinder and pressure hose were replaced as they are known to be a problem.

Result:) .... after a good thrash around the dales the clutch pedal now feels superb . Taken a while to get it sorted but all is good.

Now got the urge to get out for some more touring in the 964

sladey · Post by **sladey** » Sun Aug 16, 2020 9:53 am

Excellent - nice fix

DustyM · Post by **DustyM** » Sun Aug 16, 2020 10:17 am

Did you fit a standard Slave or the MPL version?

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hot66 · Post by **hot66** » Sun Aug 16, 2020 12:40 pm

I’ll be honest ... not 100% sure as I got my ‘man’ to do the work so we used either opc or oem ... either way it’s all stock. Glad this sorted the problem as next step was going to be the clutch pressure plate or release arm

hot66 · Post by **hot66** » Wed Oct 07, 2020 1:58 pm

Quick job today ... the rubber air duct on the top of the fan shroud for the heater blower had split and blown a hole in itself

And new one fitted

hot66 · Post by **hot66** » Sat Nov 07, 2020 10:16 pm

On a couple of recent trips I’ve noticed after about 1hour the heat being blown into the interior reduces and the temp has to be turned up ... seems this is the result of the rear fan on the hvac control unit failing . This fan sucks air in from the cars interior over a temp sensor which is used to adjust the heat entering the cabin . If the fan fails the air around the sensor is static and as the electronics heat up in the hvac the temp sensor thinks the interior of the car is hotter than it is.

Now, the price of a replacement fan is something like £350 from Porsche !!! , but the guys on rennlist have discovered the actual fan itself is a common part used by many manufacturers, so I sourced a Jaguar one for £30 ... I gather there are even cheaper alternatives too.

So today , popped out the hvac unit with the aim of swapping over the fans ( not a direct swap as you need to remove the fan from the supplied frame and the old Porsche plug needs splicing on ) . My existing fan was fairly dirty, so I stripped it and cleaned it and reassembled. Quickly plugged it all back in and it appears the original fan is now working again

. So taking the easy route I’ve reinstalled it all and left the replacement fan in its box... will now have to wait until I get a chance for a long run out in the car to confirm it all working as it should

DustyM · Post by **DustyM** » Sun Nov 08, 2020 10:47 am

I presume you probably noticed, but the tube that runs through the unit from the fan to the small grill also gets blocked with fluff

Have you got the Jaguar part number please.

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hot66 · Post by **hot66** » Sun Nov 08, 2020 11:15 am

I did Jon , tube was clear

My denso fan is 173000-0250 ( cbc9133)
... I have noticed the plastic impeller is slight different design to the Porsche one

From renn list :

Denso part numbers: 173000-0xxx

-0410 Porsche 964.659.148.00
-790 Chevrolet
-0691 Audi A8 1994-98
-0860 Honda CR-V (european only?)
-0741 LandRover Discovery
-0770 Jaguar XJ8 1998-03
-0632 Chrysler 300M, Intrepid, Concorde

DustyM · Post by **DustyM** » Sun Nov 08, 2020 2:43 pm

Thanks James, mine works but can be a bit squeaky

I need to give my HVAC a general overhaul, but will do that when I install one of Jonny’s Aircon systems

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hot66 · Post by **hot66** » Sat Nov 14, 2020 11:36 am

Things seem to always come along at the same time .... last week noticed a damp patch under the near side front bumper... turned out washer fluid was dripping out whilst the car sat.

The screen wash tank on a normal 964 is located under the front wing, behind all the arch liners. ( the RS has a smaller tank located within the under bonnet area)

On a normal 964, the washer tank has 2 pumps, one for headlight washers and one for windscreen. It also has a low lever indicator. From what I could see, the leak was from windscreen pump .

Problem I came up against was the new replacement pumps from Porsche and all the Porsche suppliers were either aftermarket of 996 ... and they all had a different electrical connector to the one on my car ( not sure if this a later 964/993 thing ) . Not wanting to splice the loom and fit a new connector, I had a long search on Google images to try and find a similar looking pump with the same connector.... turns out this style of pump is used across the board with Audi / Vw / Porsche / Opel etc etc , but with slight variations.

Long story short, I found a Vauxhall corsa / Vw caddy pump for £12 with next day delivery) that looked the same with the same style connector

And it works ... exact fitment ( used a new genuine rubber bung seal too... seal cost more than the pump though )

Pretty chuffed with that... MOT this week

DDK - Die Deutschen Klassiker