Anyone tried an outlet thermostat on an EJ?

GeorgeL Officially Full-On Dubber

231 posts · joined Feb 2006 · 16 Jun 2006, 3:28 pm

#501331

Considering the problems that some have with making their EJ engines cool properly with the stock coolent inlet thermostat, I was wondering if anyone has simply removed the inlet thermostat and installed a thermostat in the more conventional location at the coolant outlet?

I've been talking to a fellow whose problem is undercooling due to his generous front-mounted radiator introducing a gulp of cold water to the engine when the thermostat opens on a cold day, starting a pattern of thermal cycling. We thought that an outlet thermostat might moderate the cycling. Anyone have experience with this?

George

klashniv Slammed & Awesome Dubber

82 posts · joined Mar 2006 · 16 Jun 2006, 3:58 pm

#501341

George,

I have read about drilling a small hole in the original thermostat so that there is some flow even with the thermostat closed, therefore, reducing the temperature difference when it opens.

Have also read that this might help with bleeding air out of the system too.

helbus Administrator Mad fabricator, paint and body

7,386 posts · joined Sep 2002 · 16 Jun 2006, 7:10 pm

#501414

I drilled a 6mm hole in our thermostat to allow the lower thermostat to operate in a satisfactory manner.

EJ22 into Bay Microbus - Finished project build thread- click on this spot here for info

shaihulud Custom Title Time!

1,448 posts · joined Nov 2005 · 16 Jun 2006, 8:09 pm

#501434

Well I'll be blowed. I have assumed that the thermostat on my EJ20 is an outlet model. Now I'll have to reverse my planned plumbing design. Thanks for this thread.

GeorgeL Officially Full-On Dubber

231 posts · joined Feb 2006 · 17 Jun 2006, 6:10 am

#501565

shaihulud wrote:Well I'll be blowed. I have assumed that the thermostat on my EJ20 is an outlet model. Now I'll have to reverse my planned plumbing design. Thanks for this thread.

Ah, unintended benefits! Good!

I'd heard of the enlarged bleed hole to moderate the temperature in the radiator. The theory is sound, but for those of us who might travel in subfreezing temperatures it might result in long warmup and perhaps even overcooling.

Even with an outlet thermostat you need to have a little bleed hole to move warm water from the engine to the thermostat so the thermostat can sense the temperature. I wonder if Subaru's intent was to create a design where the radiator flow could be zero until the engine reached operating temperature?

George