CriticalCommonCooling

Subaru Forester: EJ20 Water Pump Plastic Impeller Wear

EJ20 Water Pump Plastic Impeller Wear is a common cooling fault on the Subaru Forester on the 1997–2002 cars, and we rate it critical. Putting it right costs $400 to $900 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 50 documented faults on the Subaru Forester.

Vehicle: Subaru Forester
Engine: EJ20
Years: 1997–2002
Fuel: petrol
System: Cooling

This page covers the Subaru Forester as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Subaru Forester faults50 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph of the Water pump yet. We would rather show none than show a picture of a different part.

What goes wrong

The EJ20 water pump uses a plastic impeller that degrades over time, shedding material and eventually spinning freely on the shaft with no coolant flow. Failure causes sudden overheating with no prior warning. The pump is driven by the timing belt, so replacement is typically done concurrently with timing belt service. Documented extensively on Subaru enthusiast forums and by NZ/AU mechanics as a near-inevitable service item on high-kilometre SF Foresters.

What you would notice

Sudden overheating with no visible coolant leak
Coolant temperature rising rapidly under load
No heat from heater despite engine reaching operating temperature
Coolant flow absent when cap removed at idle (technician check)

How to check it

Where to look. Front of EJ20 engine, driven by timing belt

Confirm timing belt service history; check whether water pump was replaced at the same time; inspect coolant colour for impeller debris; request workshop check of impeller integrity if history is unknown.

Parts involved: Water pump.

What it costs to put right

$400 to $900 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

Ask the seller

“When was the timing belt last replaced and was the water pump done at the same time?”
“Has the car ever overheated?”

Now check the Subaru Forester you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.

Not sure what you would be paying for? See what a full KickTyres check includes.

Where this comes from

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.

Subaru Forester buyer questions

Is ej20 water pump plastic impeller wear serious on a Subaru Forester?

We rate it critical and common on the Subaru Forester. The EJ20 water pump uses a plastic impeller that degrades over time, shedding material and eventually spinning freely on the shaft with no coolant flow. Failure causes sudden overheating with no prior warning. The pump is driven by the timing belt, so replacement is typically done concurrently with timing belt service. Documented extensively on Subaru enthusiast forums and by NZ/AU mechanics as a near-inevitable service item on high-kilometre SF Foresters.

How much does it cost to fix on a Subaru Forester?

$400 to $900 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Subaru Forester years are affected?

Our research records this fault on the 1997–2002 Subaru Forester. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.