Power steering fluid

[Sandspider]

Hi all

I seem to have a leak from my power steering (reddish fluid dripping from the front right of the car). Need to get under it and see where it's coming from, but first question, what's the correct stuff to fill it up? Dexron III ATF? Is that even available any more?

Are there any likely contenders for a leak from this area, before I start burrowing underneath?

Finally, the steering is now (obviously) quite heavy. Will driving it without fluid / with low fluid damage the pump?

The power steering belt was replaced quite recently, but I seem to be getting other steering issues now.

Thank you.

 

[bmnelsc]

Dexron II is the correct fluid and it is getting hard to find. IIRC you can use III but IV is a no-no. Mine leaked mostly around the hose connection to the reservoir - wept even after tightening. I found myself away from home and needing fluid and all I could find was modern, clear "power steering fluid for European cars". I topped up my reservoir (about 1/4) with this stuff and three years later I have not had to add fluid. No harm seems to have been done but doesn't leak anymore.

Heavy steering...my S2 feels like the manual steering on a 242 Volvo - nowhere close to modern cars - but the fact that you can turn those big tires with one hand when nearly stopped means the assist is working. I can't compare to other 944s so I have to assume mine is "normal". Running the pump low on fluid will bring up the heat which will shorten the life of the seals...more leaks and you certainly don't want to run it dry.

Other than leaks from a pump running the proper speed (therefore pressure) there should be no ill affects from a new belt. When you top up the fluid - start the engine and then turn the steering wheel from lock to lock a couple of times. This should purge any trapped air in the system. Check your fluid level again after you do this.

 

[Sandspider]

Thanks Bruce, I'll go and have a search for Dexron II and III. Hopefully I've had a hose pop off rather than a major breakage.

As for difficulty of steering, mine is SIGNIFICANTLY harder to steer when the PS isn't working. Yours sounds like it might not be quite right? When working, mine is only a wee bit heavier to steer than my modern Skoda. (Which is a big, hefty estate car with wide wheels)

 

[dlknight]

Just throwing this out there - Porsche issued a service bulletin for the 964 and 993 that stated Pentosin CHF power steering fluid could be mixed with and used instead of ATF fluid in the power steering system. I believe the 964 (and perhaps 993) share the same or similar power steering pump to the 944. They switched to power steering fluid in the 90s and stopped using ATF, transcript of the bulletin below.

Pentosin CHF 11S is no longer available but apparently the replacement is CHF 202.

Steering Gear - New Type Oil Group 4 Number 9606 Model 6 Cyl. Part Identifier 4800 June 11, 1996 Subject: New Type Oil for Steering Gear ATTENTION: Service Manager / Service Technician Model Affected: 911 Carrera 2 and 4, Model Years 1989 to 1994, 911 Turbo, Model Years 1991, 1992 and 1994, and 911 Carrera (993) 1995 Model Year on Concern: In production, the power assist steering system is now filled with Pentosin CHF 11S fluid (green in color). General Information: From the following VIN numbers, the power assist steering system is factory filled with Pentosin CHF 11S fluid: As of March 25, 1996 from VIN: 99 9 TS 32 3082 Coupe 99 3 TS 34 1781 Cabriolet 99 8 TS 38 5439 Targa Pentosin has been selected for use because of better and more uniform viscosity behavior at low ambient temperatures. Vehicles of the model types affected produced before the above mentioned VIN numbers used ATF in the power assisted steering system. It is now permitted to use Pentosin CHF 11S in these vehicles as well. ATF fluid and Pentosin CHF 11S fluid can be mixed. In vehicles produced before the above mentioned VIN numbers, Pentosin CHF 11S fluid can be used to top off the fluid reservoir. The 1996 911 Turbo uses Pentosin CHF 11S fluid in the steering and hydraulic assisted clutch systems. In this system, ATF must not be mixed with Pentosin CHF 11S. Vehicles having repairs made to the steering gear that involve loss of the steering fluid should be refilled with Pentosin CHF 11S fluid. Parts Information: Pentosin CHF 11S fluid (1 Liter), part number - 000 043 203 33

 

[Sandspider]

Thanks DLK.

Just purchased a litre of Dexron II from carparts4less for a very reasonable price. The fluid in there now is red, which I think is Dexron, so I'll stick with that.

 

[vitesse]

I have always used Comma (ie Esso) ATF oil which is red to top up any power steered car I've had from Rover SD1 Vitesse through to current BMW's,,a previous 964 & the current 924S my wife drives.My 924S is manual & provided you don't stop ,the steering is as light as any of the others'[]

Not used much of it as had no major leaks.

 

[IanK]

Thanks Bruce, I'll go and have a search for Dexron II and III. Hopefully I've had a hose pop off rather than a major breakage.

As for difficulty of steering, mine is SIGNIFICANTLY harder to steer when the PS isn't working. Yours sounds like it might not be quite right? When working, mine is only a wee bit heavier to steer than my modern Skoda. (Which is a big, hefty estate car with wide wheels)

Halfords do Dexron II

https://www.halfords.com/motoring/engine-oils-fluids/gearbox-oil/halfords-automatic-transmission-power-steering-fluid-dii-1l

When mine was leaking it was from 2 places. From the reservoir hose (whicj was sorted with a trim and tighten but them from the rack itself. The latter meant I needed to get an exchange rack and its now perfect.

Still heavy compared to a modern car though.

When the fluid dropeed whilst out on the road I took the beklt off so the pump wouldnt get hot.

Ian

 

[Sandspider]

I checked the reservoir hose and any other easily accessible bits and couldn't find a leak. Judging by the amount of fluid dripping, a pipe has come off somewhere, or there's a big hole. Will try and get under the car this weekend to investigate further. I do hope it's not the rack. What sort of cost was the new / refurbed rack, may I ask?

 

[Waylander]

the PAS oil coolers tend to corrode when the car is left outside, below the OS headlight,

 

[Sandspider]

Hmm. Mine does live outside, and the leak is below the OS headlight somewhere...Is that a big job to replace? A quick google suggests it's essentially a coil of tubing tucked into a fairly tight space.

Cheers.

 

[IanK]

I think the exchange rack was around £500 from memory.

Ian

 

[Waylander]

That was expensive,

Power Steering Services in South London do a full refurb of your rack for £275

On the 968 to replace the pas cooler you have to dismantle the entire front bumper engine oil cooler and all sorts of bits to get it off but it might be a hose split or a clip rusted off, the bigger issue is you have to take loads off to find the leak

 

[IanK]

That was expensive,

Power Steering Services in South London do a full refurb of your rack for £275

memory failure - I checked and it was indeed exactly £275 - Western Power Steering

Ian

 

[Sandspider]

Thanks chaps. £275 wouldn't be the end of the world if it is the rack. Still hoping it's just a hose popped off. No chance to look at it today, and it's going to rain for the next week at least! Ho hum, I'll get wet then!

 

[Sandspider]

Right, I've managed to get underneath it, and there is indeed a small leak from the power steering cooler, under the driver's side headlamp. A small patch of corrosion with a pin hole in it by the looks of it. Can this be patched / sheathed in something, or is the pressure too high?

Waylander wins the prize - Some carboard soaked in Dexron II!

 

[vitesse]

I should imagine a hydraulic union fitting -the type with conical nuts /olives could be fitted if the pipe is a standard diameter ,providing you can use a small pipe cutter the type that plumbers use,after draining enough fluid out & cleaning the pipe up in the repair area.

Is there enough room?

 

[Sandspider]

Hmm, that makes sense. The leak is in the upper layer of the pipe, so not that easy to get to, not by me anyway. But I imagine a garage with a lift & more tools could get in there. Good thought, thanks.

 

[Waylander]

I would imagine that that's just the weak spot the rest will be just as thin, I don't think there is much pressure there as its the return to the tank.

I believe a new one 944 347 459 03 is £168 from Porsche, not really worth faffing around and possibly having to do it twice

 

[Sandspider]

There's one spot that's quite corroded, about 2.5cm long. It's under where a drip falls from the back of the headlamp unit I think. The leak is in the centre of that, and the rest of the pipe feels firm and solid. The hole seems to expel fluid with a fair bit of pressure, it comes out in a little jet!

Will get it to my garage and see what they think. Thanks for part number, and good to know they're still available from Porsche.