226 replies to this topic

[hanra]

How's your ignition timing?

[S pack]

dropping it in boiling water wont give you a read on it working properly, you need to bring water up to the boil with it in it, preferably using a thermometer to see what temp it opens at.

Agree, you need to heat the water up with the thermostat suspended and fully submersed in the water. A thermometer is a must to see what temp the thermostat starts to open and at what temp it is fully open.

Just because the thermostat is near new doesn't mean it is functioning correctly. Also what temp is your thermostat rated at? Maybe you need to go for a lower temp thermostat?

[S pack]

Test it without the thermostat and see how it goes. More than likely the thermostat is faulty and causing the engine to run too hot.

[MustardGTR]

Do you have an aftermarket or original temp gauge? If original temp gauge its worth checking for correct operation of sender.

[REDA9X]

What condition is the timing cover in? If it's corroded behind the pump the water will cavitate. You say the pump is reasonably new but with a new radiator it's still doing the same thing. If you bought a cheap pressed metal pump take it off and throw it as far as you can. Get yourself a cast impeller type pump. Everyone loves to blame the fan but they don't do anything at 80km/h anyway. I certainly would not be throwing an AU fan setup away for an old clutch fan, Holden and Ford stopped using them a long time ago for a reason. My piddley little 10" standard thermo fan and 2 core radiator did the job ok, they did the job ok for the A9X race cars in full race trim so I'd be looking at the system as it exists now before trying new things. I'd check and see if it's actually getting hot too, check and see if the radiator is cold or not that's a giveaway of poor circulation.

[REDA9X]

Popular myth. What is correct is that for most setups ram air flow at higher speeds is more than adequate. On marginal setups having an engine fan operating at cruise can make the difference, not saying that is the case for our OP as there is perhaps a trickier prob given that no mention of the ambient temp..

Exactly, if it was working correctly in the first place the fan would be doing SFA, there is a bigger issue here, plenty of race cars dont even run fans at all

[REDA9X]

Those tin impellers are crap you need the one in the second picture with the flat back on it, much better. I rememberwatchinga test of these a few years ago and all the tiin ones did was cause air bubbles.
People seem to think they can fix problems by fitting big fans and radiators, but unless you are for some reason generating massive under bonnet temperatures with intercolers turbos and massive HP, the system should only need basic upgrades. A 400hp 308 will operate fine with the standard 2 core radiator and Holden water pump provided everything is working correctly, if not therein another issue. Holden and ford spend massive amounts of money testing these things under varying conditions so stick to the basics.

[ls2lxhatch]

I cant recall specifics now,but i asked for the lower opening temp one of the two that the guy at Auto pro had in the shop.

Looks like i'll have to try take the Thermostat out again an test it correctly, or I could just leave the Thermostat out?

I dunno exactly what the problem is but I know years ago when I first fitted the AU Fans and they kicked on,the Temp use to absolutely rocket downwards!! but like today they whirled away full rip for about 2 mins and the temp had only gone down 5 Degrees!!?????.

Unfortunately I have no fan controller yet......,they just stay off and when my temp guage shows 95 degrees the fans kick on then kick back off ( or use to) when the temp was back down at 70 or so but as I said even using no Fan Controller the fans use to make the temp soar down!.

In my opinion 5°C in two minutes is not bad considering the temperatures in Perth lately. What was the ambient temperature at the time?

You need to know what temperature the thermostat is designed for. The standard thermostat should be trying to maintain a temperature of around 83 °C. In theory it should be impossible for a cooling system to cool the engine below the thermostat temperature. You can not expect the fans to bring it back down to 70 °C with a 83 °C. thermostat.

I would have the thermo fans kicking in well before 95 °C if the engine will normally run at 83 °C.

A high flow thermostat like the Tridon TT2000-180 will help with water flow.

You should be able to determine at what temperature the thermostat is opening by running the engine from cold and seeing at what point the temperature stabilizes and the top hose gets warm.

The infra red temperature guns make diagnosing the system a lot easier.

[S pack]

Where can I get the correct Water Pump from then!??,what a pain in the ass! ,now I gotta find the right one and take my car apart again.

If anyone knows where I can get the Pumps that REDA9X is talking about let me know asap!! I take it the problem is cause the Fins are open and not contained in an enclosed Circle type impeller so it hampers the flow??

Before stressing out about the water pump remove the thermostat, check the opening temp stamped on it and test it in hot water with a thermometer to find what temp it actually starts to open at and what temp it is fully open at. Process of elimination. One thing at a time.