80 450SL - Poor acceleration & aux. fan

[ej450SL]

Purchased the 450 last year (208k kilometers and burns no oil) and it has always been slow on acceleration, but this spring it is to the point that you can put your foot to the floor and it takes several seconds before it begins to accelerate. Secondly the auxiliary fan is always running and is very noisy. Should it be running on cold start up? If not, where is the thermoratic control for it located?
Thanks for any assistance.

[450slcguy]

Start with the basics if you haven't already:

Plugs/wires/cap/rotor

Replace air filter

Set engine timing to 5 deg. btdc

Test Fuel pump and replace the filter

Check/replace ignition coil

Check all Engine Vacuum lines for leaks

Adjust air/fuel mixture

FAN - Replace temp. sending uniit on top of thermostat housing.

Do all of the above and she'll run much better.

[Nascar Fan]

I second all that. Air/fuel mixture (warm-up regulator) was a problem on mine, but I did all the above first.
Also check the mechanical advance in the dist.

If your AC is switched on or there is a problem with the servo your fan will run. It made to run anytime the AC is on.

[ej450SL]

Thanks for replies, I will start on them in the morning.