The stat in a benz is not an on off valve like a garden hose. Off on is how a traditional american made car stat works. With an on off valve you can cool fine without it but the car will run too cool under light loading.

A benz stat is a diverter valve. Its more like a switch in a rail line. When the engine is cool the stat diverts all water back to the head without ever going into the rad. When its hot it diverts all water to the rad and none to the head directly. It goes to the head after passing through the rad in that case.

If you remove the benz stat you will allow the water to seek its own course and it will send about half directly to the head and half to the rad. Thus when its really needing cooling its only cooling half the water and the car will run hot.

If its cold outside and the car needs to warm up half the water will continue to go to the rad and it will not warm up.

Drilling holes in the stat will only reduce its effeciency. A good stat working the way the system is designed to be operated cannot be beaten.

If you don't understand look in your repair manual for a diagram of how it works.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.