I jsut heard about some people doing this yesterday and was not understanding why someone would do that??

I think the theroy is to let coolant flow by even when the thermostat is closed. The way a thermostat is engeneered is the way that it was meant to work. If you are trying to make it do something other then what it was intended on doing then get another temp thermostat in my opinion.

Doing that in my opinion will not give the coolant sufficent time to heat up, therefore making your heat not ever get up to temparture, and resulting in cooler heat.

Most T Stats come with a little hole in them to allow coolent to flow to the bulb side of the T Stat. If the hole is not there I always drill a small 1/8" one to allow the fluid to go to the bulb side. If that is not done after new T Stat installation it is possible for the T Stat to not open properly on initial startup because the bulb does not have coolent arround it and heat transfer does not take place to the bulb to open the T Stat until way to late which can cause overheating.

However, that is probably not why they are drilling holes, they are probably drilling big holes in the misguided thought that it will increase coolent flow thereby aiding cooling. What that will actually do is just increase warmup time and can actually aggrevate overheating because the coolent will not be restricted enough and stay long enough in the radiator to cool down before it goes back to the engine block. The purpose of the T Stat is to regulate the coolent temp and if it is working properly and the cooling system is adequate you should never have an overheating problem

not a good idea:eek:

:iagree: That just doesn't sound like a sound idea!