heater warm up ?

Why not plug in the block heater? My water is already at 100 degrees.

ScottG wrote:
The thing I don't understand is how new gas engines warm up so fast.
The 6.4L in our other Dodge starts blowing nice warm air within 30 seconds of starting no matter how cold it is outside. Almost makes me think there's a electric coil in there.

I enjoy that "feature" in my 5.7L Ram too. Combined with the heated seats and steering wheel, it's heaven this time of year.

If I know im going to be driving it in the AM I just plug it in the night before wall la instant warm air

I let it was up for a few seconds and drive normally with Tow/Haul on until I get heat. Normally it heats up pretty quick even in minus temps.

Still a thermostat can fail open or partially open and cause the slow to warm up and produce heat issue. Need to remove and inspect.

http://www.motoradusa.com/fail-safe.aspx

Apparently what I was taught several decades ago has gone the way of the 3,000 mile oil change ;)

time2roll wrote:

wanderingbob wrote:
Assume that the only issue was to get heat into the truck cab as soon as possible ! Would you start truck and get up to up to hiway RPMs and speed quick or would you maybe travel slower in a lower gear .
Highway speed RPM sounds good except that puts colder air across radiator and motor .
What do ya think ?

Make the engine work for fastest warm up. No need for full throttle but get it up on the highway for fast heat. If it still seems slow to warm check or replace the engine thermostat. The thermostat is made to fail open and can circulate coolant to the radiator when still cold.

Thermostats are not made to fail in the open position unless you buy one that is made just for that purpose. They fail closed ,open, or partially open. Very frequently when they fail it is closed because they start out closed and can not overcome the friction of opening.

On another note, there is almost no coolant flowing through the radiator when cold, until the engine block has reached operating temperature and the thermostat then opens. Until then there is flow from the engine block to the heater core and back with the heater on.

When my old truck was new I would let it idle for a few seconds before I started driving and then I had heat within a mile. When the truck got older I would let it idle until it was fully warm - the colder it was the longer it idled - and then I would drive. Later when I found out where the cold air was leaking in, I fixed it and went back to letting it idle for a few seconds before I took off.

ShinerBock wrote:

ScottG wrote:


(Sorry, off topic) The thing I don't understand is how new gas engines warm up so fast.
The 6.4L in our other Dodge starts blowing nice warm air within 30 seconds of starting no matter how cold it is outside. Almost makes me think there's a electric coil in there.

Two words... thermal efficiency.

Due to the high compression ratios/expansion ratio of a diesel, most of the heat(energy) made during the combustion process is used as work and does not need to be carried away in the coolant. Gasoline engines are less efficient at utilizing the heat(energy) as work from the combustion process and more heat gets soaked into the engine which gets carried away in the coolant. Therefore a lower compression ratio gasoline engine will get the coolant to a higher temp much faster due to how inefficient it is at utilizing the energy from the combustion process versus a diesel.

Sorry for the "engine nerd" answer.

Sounds good to me!
Still, I am amazed when I get heat before I leave the driveway. Never had a car that would do that before.

I prefer to get on the road as the engine heats up faster, light throttle. However, I usually let it warm up on the driveway as I won't leave until the windshield clears.

ShinerBock wrote:

ScottG wrote:


(Sorry, off topic) The thing I don't understand is how new gas engines warm up so fast.
The 6.4L in our other Dodge starts blowing nice warm air within 30 seconds of starting no matter how cold it is outside. Almost makes me think there's a electric coil in there.

Two words... thermal efficiency.

Due to the high compression ratios/expansion ratio of a diesel, most of the heat(energy) made during the combustion process is used as work and does not need to be carried away in the coolant. Gasoline engines are less efficient at utilizing the heat(energy) as work from the combustion process and more heat gets soaked into the engine which gets carried away in the coolant. Therefore a lower compression ratio gasoline engine will get the coolant to a higher temp much faster due to how inefficient it is at utilizing the energy from the combustion process versus a diesel.

Sorry for the "engine nerd" answer.

Gasoline engines run rich when there cold therefore producing heat faster and run hotter to be emissions compliant. They're designed to do this and not a function how efficient they're at utilizing heat.

During college summer breaks I worked for Texas Department of Public Transportation Maintenance and the guy I worked with would always have me put his lunch wrapped in foil on the diesel engine intake manifold when I would check the oil in the morning so his food would stay warm for lunch. That engine would run all day and barely get warm but was very fuel efficient. This was a non turbo diesel engine.