Hi All,

Just chasing some advice on a cooling issue with my 99 WRX.

Having just done a full service (including timing belt & new water pump) it seems my radiator fans do not want to turn on.

The fans work and are plugged in properly (I checked by connecting the green connectors under the dash and turn the key 2 times).

The water pump is new, as well as the thermostat and gasket.

I'm not leaking any coolant (that I can see...).

The lower radiator hose is getting warm (hot). I thought that would indicate the thermostat is open and coolant is flowing through? Or perhaps some convection moved the coolant around without the thermostat being open.

I thought I did a good job at getting the air out of the system. The hot hose at the bottom of the radiator makes me think I did. Is that a fair assumption?

I'm going to retry burping it all tomorrow using this technique.
Everything You Ever Needed To Know About Cooling Systems - Subaru Impreza GC8 & RS Forum & Community: RS25.com
(quite a bit on info on that thread!)

When I refilled the coolant (all genuine Subaru) I used about 1-1.5 litre of some older coolant I had left over from last time it was drained. When I looked at the funnel filter, there was a very fine sediment film across it. The rest of the coolant that went in was brand new. To be honest I would be surprised if that is causing the problem as it was a tiny amount, but please correct me if wrong.

My engine temp gauge is sitting in the normal position. I assume this would move towards hotter before I do any engine damage?

Aside from burping the system again, are there any other reasons the fans won't be coming on?

How long would it normally take for them to come on? I seem to remember about 10-15 min. This time I went for a spin about 10 min and waited for probably 10-15 min at idle and they didn't come on (unless they came on whilst driving, but I don't think they did).

I'm only asking prior to burping again as having done a fairly major service I'm a little nervous with it all!

Thanks in advance for any help/tips.

(P.S.Timing belt top tip, crankshaft pulley bolt is a bitch. Big breaker bar and car in 5th/on the brakes eventually cracked it!)

I'd keep an eye on the temp gauge and wait longer for the fans.
The gauge is indicating that it is not overheating. Might be cheap insurance to look at a separate temp gauge if concerned.
Do the fans come on with the a/c?

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MY00 WRX. 89 Prelude. 99 CRV

I have a 15$ Bluetooth obd2 adapter and torque app and my fans kick on like clockwork when the coolant temp reaches 96c.. Usually doesn't reach this from just idling... I have to drive around for a bit then stop and idle and it starts creeping up . Then the fans kick on and take it down to about 89/90. Pretty sure this is standard on all WRX's. Not sure if the Bluetooth obd2 things work with gc8's too.

Also worth mentioning the temperature gauge in these cars is not exactly a good measure of if your car is running too hot or cold. Mine will sit at "normal" between about 70 to 100.That's why I love using the Bluetooth adapter.

Thanks for the replies.

Fans come on with air con. I will try leaving it idle for longer tomorrow.

I think that would work with my year. Any idea if they're sold in Perth? Sounds like a neat thing to play with anyway!

My cars fans come on at 93 degrees Celsius - normal operating temp is 86/87c (Power FC handset).

Sitting idling once well warmed (5km drive) it takes 10mins for the temp to to lift from 87 up to 93 with a 20 degree ambient temp.

Hot is over 108c.

Panic is 115 haha.

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[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]

Had another crack at burping the system and all seems to be running well. Cheers for the help anyway. Just wanted to cover all bases after doing all that work on it.

Ebay "Bluetooth obd2"

Head gasket is 130

http://m.ebay.com.au/itm/400775051498?nav=SEARCH

Word of caution: they dont work on all obd2 equipped cars, it doesn't work on 2003 lancer and 2005 carolla. So might not work on 99 wrx.

using the Perth-WRX mobile app

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MY08 STI 422whp at 1.5bar on E85, built by Diversion Garage, assembled and tuned by EvoR

Update from new owner: 375whp at 1.4bar on 98, at Tokyo Motorsport