AC Retrofit for a Maruti 800

Forewords:
With the summers having already set-in, it’s time to check one’s Car AC System, to ensure that it performs well when needed most. Just remember that a Car AC in principle is quite like the ‘Split-AC’s that have now become popular for home/office use - except the fact that the ‘outdoor unit’ is housed in the car’s engine compartment and the ‘cooling unit’ inside the cabin, in the dashboard.

With the M800 still being the highest in numbers on the roads and most people being some what penny-wise pound-foolish, a lot of them buy a ’standard’ M800 and then try to retro-fit an AC ‘Kit’ as cheaply as possible. Naturally, they don’t deliver what they promise and the Kit Fitters wash off their hands by finding faults in the car/engine. So here’s what you can keep in mind while going in for an AC-Retrofit on an M800…

There are ONLY 2-AC ‘Kits’ suitable for an M800 - one is the Subros’ that comes as an OE fitment and the other is the after market ‘Sanden’. The rest/cheaper wayside ones are mostly ‘mix n (mis) match’ and as such, they seldom work satisfactorily, if not kill the engine sooner than later by overloading it. Besides, all car AC’s can rob a car of 10-20% of its power and associated fuel consumption - for obvious reasons.

On the other hand, while it cools better than the Subros’, due to it’s larger compressor and condenser/cooling coils to match, the drawbacks of a Sanden Kit for the M800 are - i) Compressor overloads the engine more than Subro’s, ii) if its front end Condenser is ’skived’ type, it is unsuitable for the dusty Indian climate.

As such, there’s no Kit better suited for an M800 than the OE/Subro’s and that too installed either by a competent MASS or a Subro’s Authorised Service Station. Such a Kit including the 120-Watts Radiator Fan upgrade costs around Rs: 18k lot. Make sure that the price quoted to you for it includes the replacement 120-Watts Radiator Fan, which is a must for both Sanden as well as Subros.

However, it must be kept in mind that Cars older than, say, 3-yrs and specially the ones having Aluminium Radiators are most likely to suffer from overheating after a Retro-fit even entirely as recommended above - due to the inevitable scale formations within the Engine/Radiator.

Should that happen, then it’ll call for a ‘Cooling System Flush/de-scaling’ - using one of the many well-branded products available in the market - exactly as per instructions given on their packaging.

However, having decided to go in for either of the two, M800 being under-powered as it is, to get the best results including on the life of the engine, one must ensure that - i) with AC on, always drive in one gear lower than what one would other wise do w/o AC i.e. in 3rd at speeds below 40 kph, in 2nd below 20 and so on, ii) get the std 80 watts radiator fan replaced by a 120 watts ‘Denso’ one. This is reqd even with Subro’s kit as otherwise your engine is bound to overheat in city traffic and damage itself in summers. The outgoing fan has hardly any resale value so you may as well keep it as a contingency spare and iii) if the condenser fins are ’skived’ type, make sure that you have them medium pressure washed atleast once a month and less frequently if they’re of ’serpentine’ type. Further, this must be done even in winter times when the AC is not in use and ALL car AC’s as such should be switched on atleast once a week for 15-20 minutes in winters also, to keep their Compressors well-lubricated and thus in good shape to face the next summer.