Problems with Hydraulic Power Steerings

Preamble
Last week we had a look as to how Power Steerings appeared in India and the existing divide between ‘Electronic’ and ‘Hydraulic’ Systems. Given its relative simplicity and thus the ease and cost of manufacture, coupled with the fact that it hardly requires any maintenance ever, EPS’ are gaining popularity today.

All out R&D efforts are on towards refining them to give that hitherto missing ‘road feel’ and manufacturers have met with considerable success in the recent past also, to the extent that the world famous Toyota-Lexus switched over to EPS a few years ago.

EPS’ can be basically of two types – one where the power-drive electric motor is steering-column mounted and the other where it’s on the Steering Rack in the engine compartment, in the form of a ‘cassette’ assembly. The former finds favour with smaller cars like the Alto/W-R where it can be easily accommodated under the dashboard. The latter becomes inevitable for heavier cars, like the Swift.

Notwithstanding, even today there’re appreciable high-end car makers like the Merc and BMW who continue with HPS’ in most of their models. Nearer home, while Maruti have more or less switched over to EPS, Hyundai have also made a switch to EPS on their ‘i10’ to begin with.

And like any other complex/belt-driven hydraulic System, one can have problems with an HPS. Sample this real life QnA, for an insight into the matter…

Question
I have Maruti Esteem-vx 1997 model with power steering. Recently I got it serviced from a Maruti Authorised Service Station. In their service report, they’ve mentioned that power steering oil leak needs repairing. They’ve also informed me that tho’ the oil level is not reduced but it needs urgent repair. They have quoted a whopping Rs. 6,500/- for the repair work. They’ve also stated that if it is not repaired now, then later on it will have to be replaced at a cost of Rs. 30,000/-! Should I get the job done? What if I do not get it repaired, whether steering will stop working? Can I get the same repaired from some good workshop at a lower price?

Answer
In Hydraulic Power Steering Systems, there can be such a thing as an ‘Internal Leak’ in the Hydraulic Pump - some thing like excessive ‘blow-by’ in engine cylinders due to worn-out piston/rings, resulting in loss of ‘compression’ and therefore, loss of engine power.

The result of such an internal leak is that the hydraulic pump doesn’t develop enough pressure and therefore, ‘power assist’. Consequently, the steering feels appreciably heavier than what it should. Its other manifestation would be higher than normal noise emanating from the pump.

If neither of these two is happening in your case, then in all probability the Garage is trying to make a fast buck, under the pretext of changing the internal sealing rings of the pump and scaring you further with an imminent/high replacement cost if not heeded to.

Over and above these two symptoms, if you did not mention a ‘heavy steering’ in your schedule of ‘demanded repairs’, then you can ignore their suggestion. At best you can ask them to demonstrate to you on what do they base their diagnosis.

And btw, to get max life out of an HPS, it’s advisable to restore the steering wheel to ‘straight ahead’ position after parking and before switching off the engine. This way, the stress on the Pump is minimal when the engine is started next time. As can be imagined, such a contra doesn’t apply to EPS’s.

To sum-up, it’s unlikely that any Garage would turn up with such a recommendation w/o the owner having complained of a heavy or a noisy steering. Therefore, I feel you should take an independent second opinion, if necessary.