Engine Roar at first start

[elees]

I have noticed that my engine has a significant roaring sound the 1st time I start it in the morning when it is in around 40-50 F degrees. Is this a normal condition? It goes away in when I get to cruising speed.

I generally don't give much warm-up time as I read somewhere in the forum that it is not necessary.

thanks in advance for replying.

Ed

[DmaxMaverick]

It's normal. What you are hearing is the engine cooling fan. The fan clutch has fluid in it, and is subject to increased viscosity and settling while the engine is not running. Once the fluid gets circulated and warmed up, the clutch operates normally. All viscous clutch equipped vehicles do this to some degree, whether it's heard or not.

[Mark Rinker]

I have noticed that my engine has a significant roaring sound the 1st time I start it in the morning when it is in around 40-50 F degrees. Is this a normal condition? It goes away in when I get to cruising speed.

I generally don't give much warm-up time as I read somewhere in the forum that it is not necessary.

thanks in advance for replying.

Ed

In SoCal, its probably correct that warmup time is minimal. However, I have seen people (my wife) drop a car in gear and go before the keys have stopped swinging in the ignition, or the oil pressure gauge has started to register properly.

After sitting for more than 24 hours, I'd give at least a cursory 45 seconds to 1 minute for fluids to reach operating pressure and oil to get to the top of your engine and rings.

Just my opinion. Backed up by miles, not hard science.

[EdHale]

I always roar in the mornings, don't the rest of you?

Ed

[elees]

It's normal. What you are hearing is the engine cooling fan. The fan clutch has fluid in it, and is subject to increased viscosity and settling while the engine is not running. Once the fluid gets circulated and warmed up, the clutch operates normally. All viscous clutch equipped vehicles do this to some degree, whether it's heard or not.

Thanks for the reply and education.

Ed

[BradL07]

Ed,

I roar about every third morning, regradless of temperature, and will sometimes roar on the way home in the evening!

Brad L