Radiator Fan Damage to Radiator

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Radiator Fan Damage to Radiator

First read this email which I noticed a long time ago [2001]:

“My 2000 Subaru Outback has on 2 separate occasions suffered major radiator damage from the plastic blades of the left electric fan, noticed after passing through shallow water on a farm road. Lucky on each occasion to notice rise in temperature before "cooking" the engine.

The first time, on its first outback trip, the farm road had some short pools of water no more than 8" deep & 40 ft long. I've travelled this road numerous times before in a variety of vehicles & in far worse conditions, & other than bogging, without incident or damage. Arriving at the main road after some 8 kms I noticed a rise in temperature & on investigation found a broken fan blade embedded in the radiator & the radiator extensively damaged.
Being some 600 kms from home & 300 kms from the nearest Subaru Dealer & having much valuable video equipment on board, this was a real problem. Fortunately, being a Gold card member of the NRMA, they arranged a tow to & overnight accommodation at Coonamble & next morning a flat top tow to Mudgee, where the fan & radiator assembly was replaced at a cost of $1237. Whilst held up by the road, a local Outback driver stopped & on learning of my problem, advised me that the same had happened to his Outback & that he took the fan's fuses out when approaching water. I did this for some months & had no problems.

The 2nd occasion, I observed an accompanying Holden Commodore go across the creek, some 30 ft wide & hardly hub cap deep without any problem. I didn't consider this would be a problem to the Outback & drove steadily through. I was astounded to shortly after notice the temperature gauge rising & on investigation found that this time, although not broken, a fan blade had contacted & punctured the radiator. I was able to remove the radiator & patch it with Selley's Epoxy, which got me home.

Conventional vehicles travelled the same farm road on the same day on each occasion without incident.
I would be very interested to hear if any others have suffered similar problems.

Apart from this major fault, I have found the Outback to be the best performing all round vehicle of the 10 FWDs & 20 conventional vehicles I have owned to date. By Alvin Lawson. <lawvideo@ihug.com.au> Thursday, 8 February 2001”

Comment:

This is a very common outcome for many vehicles of many makes. I sympathise with Alvin, but wonder about the speed, and depth of the water. What happens is when a large dense amount of water is forced through the radiator (and the air-conditioning radiator in front of that), the electric radiator fan/s become a propeller and the blades can bend forward and cut into the core of the radiator as described.

He is also very lucky not to ‘cook’ the engine as very often the temperature gauge will not register any change in temperature after losing some coolant. I do not know of any car having a ‘low coolant’ alarm*, a major failing by manufacturers - borne out by plenty of ‘cooked’ engines because of lost coolant. I know that even with a total loss of coolant the engine temperature ‘gauge’ can go lower as the thermistor is then exposed to air.

There are (usually) two electric radiator fans controlled by the computer. They cycle 1 or 2 on and off regularly according to the engine coolant temperature. They are also both turned on as soon as the air-conditioning (A/C) is switched on; and when the A/C thermostat cycles.

You can take the fan fuses out, or unplug the fans at their sockets (on the radiator frame underneath), or fit a cut-out switch to both fans*.

Perhaps on later model Subarus the fan blades, blade shrouds, front air intake, bumper and grill are different and it may no longer be an issue. The safest answer is to walk the obstacle which would be standard practice when 4wdring at creeks, rivers, puddles, bogs etc. However, I would consider it a possible issue and suggest doing something with the wiring, and fit a coolant alarm*.

Ian Johnson @10/2014