Has any one tried to cover the radiator to keep warm?

Without a real temp gauge, I would think that would be risky.

 

Almost certainly a bad idea. If I recall the plumbing diagram correctly the Prius controls its own coolant flow to the radiator, among many other things. Interfering with it is likely to make it perform worse, not better. This is not a simple machine amenable to tinkering.

 

:roll: In such a "field expedient" approach, remember that there are TWO RADIATORS in your Prius, one for the ICE and one for the Inverter mounted parallel to each other. You couldn't "cover" one without also covering the other. Very risky at best.

 

Roadkill damage destroyed my grill, so I was easily able to put a piece of cardboard in front of my radiator - between the fins and the support post. I blocked about half the radiator. No noticeable change in performance, MPG, cabin heater efficiency or anything else. This was over about 1,000 miles - 2 weeks.

With the grill in place, it would be very difficult to get something in there to block the radiator. And it's just isn't worth it from what I have seen.

 

For cars in extremely cold environments, covering the radiator can be a fix, but not a very good one... The idea is that with less cold air blowing on the radiator as you drive, the coolant will stay warmer and will allow you more heat.

The problem is that the radiator is only half the problem - the other (and more important half) is the thermostat valve that controls coolant flow inside the engine block.

When you first start your car, the valve is completely closed and allows no water circulation to the radiator. As the coolant heats up, the valve slowly opens allowing the coolant out to the radiator to cool off.

Many cars are shipped with thermostats that open too soon for colder climates, which never provides full heating during colder months. With regular vehicles, you can get it replaced with a cold-weather thermostat which keeps the valve closed longer and allows the coolant to heat up more before it's released.

But I have no idea about cooling in the Prius, so I'm not sure if that's even an option for us northerners. Might be worth asking Toyota about though.

Dave

 

I will not offer up my Preto Prius for this kind of experiment... Even though my mileage really takes a hit now.

 

Without a temp gauge, that would just be too risky. I've always used winter fronts in the past, but I don't see how I can on this car.

Unless you can equip the car with gauges to monitor the coolant temp for the ICE and the inverter system, you won't know you have a problem until the dash idiot lights start blinking.

My folks have a 2003 Buick LeSabre Celebration Edition. My old man went to a Canadian Tire store (Or Crappy Tire as we call them here!) and picked up one of those "universal" fit winter fronts. Fits ok and seems to help for highway driving. The LeSabre has a temp gauge on the dash.

A winter front won't help in regular city traffic as the Prius has electric cooling fans. My 2000 GMC Sierra was built with HD towing, so it had HD cooling. The fan clutch would never fully declutch, so it did help running a winter front in city traffic.

My 1984 Ford F-150 with 302 V8 has two AutoMeter temp gauges: one sensor bulb is at the front of the Edelbrock intake manifold, the other sensor bulb is at the very back of the intake.

Without a winter front in temps colder than -15 C, the gauge for the rear of the block never leaves the bottom of the peg, 100 F. With the winter front, it will eventually reach 120 F. At -30 C, the front of the block never reaches 120 F unless the winter front is on.

My Ford may be an extreme example: it has a Flow Cooler high-volume water pump, a huge custom made 5-row rad, and a Summit flex fan. However, it NEVER overheats in summer, even towing!