* Aux. Fan Query...How LOUD is that thing suppose to be? *

[mgburg]

With our recent spate of > 95° F weather up here lately, my Aux. fan kicks on and I can hear that thing over the sound of the engine in my '76 450SLC.

There's nothing externally rubbing against the blades, front or back...it just sounds like I have my own personal windtunnel attached to the front of the engine.

It does shut off when the engine's shut down. That, I'm assuming, is what it's suppose to do...unlike my old (deceased) '75 Fiat 128 Wagon...that fan stayed running 'til the thermostat said it was cool enough to shut off.

Any experience with failing Aux. fans out there?

[suginami]

I replaced the auxiliary fan on my 280SE 4.5 with one from a mid '70's 450SEL, and it is loud. I can hear it over the sound of my engine, too.

I guess it's normal.

[mgburg]

Originally Posted by suginami

I replaced the auxiliary fan on my 280SE 4.5 with one from a mid '70's 450SEL, and it is loud. I can hear it over the sound of my engine, too. ... I guess it's normal.

I'm curious if anyone has the specs on this type of fan...as in; How many CFM? With that information, it might be possible to cross-reference a type of fan that has a lower decibel rating but can still push the same/more quantity of air and still run on the rated voltage/current that the original one is running at...which should be, at least 12 VDC. I'm not sure on the current rating though...

[meltedpanda]

yes they are loud, very loud, they do not continue to run with engine off

[suginami]

Can one of you check your auxiliary fan and see if it has a cover on it?

The original one in my car did, but the one I installed from a 450SEL does not.

[rocky raccoon]

I'll bet you don't have one. It does a lot for sound suppression as well as insulation.