www.RX7fb.com

KYPREO wrote: ↑Tue Jan 07, 2020 11:51 pmHOWEVER
(since when the e-fan is off, there is still airing moving through the car).

Depends on how much vs visco. I think the not working e- fan blades will restriced the flow through the fan cooling shroud more then a working visc.

Cooling water flows from the front to the rear. Cooling oil from the rear to the front. With the beehive oilcooler and e-fan i got in heat trouble with my completely cromium coated engine. Not so with the visc.

That beehive must make a massive difference (detrimentally) to cooling.

I'm still running the e-fan of a switch in the car (bad practice I know) so I watch the temperature like a hawk, but at this time of the year its actually very rare that I need to turn it on. Only when I'm sitting in traffic for a while does it start to climb, and then it comes down pretty rapidly with the twin e-bay specials I have fitted.

rotarypower wrote: ↑Wed Jan 08, 2020 11:37 pm That beehive must make a massive difference (detrimentally) to cooling.

I agree.

I put the behaviour Thomas has observed down to the beehive cooler. The coolant circuit for the beehive is as follows:

rear housing > oil cooler

oil cooler > t-piece on heater return rail

heater return rail > BOTTOM radiator hose.

In other words, coolant exiting the oil cooler and carrying any heat absorbed from the oil never passes through the radiator - it is circulated straight back into the engine and is therefore only cooled as part of the general coolant exiting the engine once the thermostat opens. No doubt, this was designed to allow the oil to actually reach operating temperature. However, it adds an additional heat load on the coolant within the engine itself. Plus the water pump has to pull through the oil cooler itself, plus an additional head of around 2 metres of heater hose/line. There's a big path the coolant has to go down.

There will also be a local heat soak effect at the position of the cooler, plus how often do people flush this things out?

Mazda didn't waste much time getting rid of the water-oil cooler idea so we can safely assume they thought it was a failed experiment.

KYPREO wrote: ↑Wed Jan 15, 2020 10:11 pm No doubt, this was designed to allow the oil to actually reach operating temperature. However, it adds an additional heat load on the coolant within the engine itself.

So it's the opposite to a cooler then and designed for emissions presumably ?

Is there a simple way to junk it? I know it's considered inefficient but didn't realise this bad.

Rich