35d Normal Thermostat Operation

[V12noise]

I thought the movable flaps in front of the radiator act as 'automatic cardboard'?

[crystalworks]

Originally Posted by SaskE70

I live in southeast Saskatchewan, and it's usually not this cold in November but we just had a storm go through. I'm not a huge fan of cardboard, I don't think it's necessary. My engine temp was low because of heating the cabin, not because of flow through the radiator. I also prefer to leave the radiator free to do its job if needed.
I'm also not concerned with the temperatures I saw. I just wanted to make a point that sometimes the thermostat is working properly but the engine temperature is still low due to other conditions.

Aren't sustained low temps bad for the glow plugs and eventually module? I had a failed thermostat without knowing it and needed to also replace glow plugs and the module. The only indication of a thermostat problem was the code for glow plug fault.

[andrewwynn]

Originally Posted by V12noise

I thought the movable flaps in front of the radiator act as 'automatic cardboard'?

Negative those flaps are to allow more air to flow though the radiator when moving but keep all aux fan air going back vs out the front when not moving.

[andrewwynn]

I know my gas engine didn't operate properly when ECT stayed below 80 and when it's below zero F I definitely block my radiator to help keep ECT in the operating range of the m thermostat. I will cover just half the radiator for temps under 10-20F but below 10F or -12c I'll switch to full coverage. I've never seen ECT get over tstat control when radiator is blocked and temps are super cold. I intentionally don't make a perfect seal so some air always gets to the radiator.

[robnitro]

The thermostat is not electronic on the D. Heater operation does drop temperatures and cardboard/ plastic helps in the winter. When you realize that 35d can do 34 mpg at 60mph, you see that there's not much heat wasted.