Andrew,  Try "power with racing" (PWR) in Brisbane who specialise in rads.  Dear but good,  Neil.

Ok, I am in just a bit warmer climate than you, winter solstice yesterday and its a sunny 22c today.

I can not see any reason to have an oil thermostat, at least here in Australia, with stock 20b cooler I could only use about 50% power before cooking the oil with a 13b.

Can't really comment about flying with cold oil. I would count that as a total victory if ever in that situation.

Aftermarket remote oil thermostats are available if you need one in the system.

I tried a 75mm thick aircond condenser as I had a couple of new ones that were originally going to be used for coolant, better but not good enough. still seeing 235-240f on partial throttle takeoffs, 175f on descent. no thermostat, but possibly too much internal restriction as predicted by Steve B.

This weekends project is to add more sensors before cooler just to possibly confirm the inevitable need to purchase & import a fluidyne. local cooler mfrs have been absolutely no help.

Andrew.

On Fri, Jun 22, 2018 at 8:59 AM, Todd Bartrim bartrim@gmail.com <flyrotary@lancaironline.net> wrote:

Some (most?) Of you are using custom or at least aftermarket oil coolers but I think there are a few like me that are using stock oil coolers. How many have removed the thermostat and plugged the bypass hole?

Do any of the non-stock coolers have a thermostat? 

A Google search on the subject shows that on the RX7 forums it seems to be generally accepted to leave it alone.

  But for our use I'm less inclined to think we always need it and it seems to be quite restrictive. 

  Of those flying without one in either stock or non-stock, how many are flying in warm climates only? Anybody in cold? Jeff? 

  I'm just concerned about winter flying especially during a long descent where it might cool excessively and then if I was required to use sudden power for a missed approach, would that cold oil be a problem? 

Todd