I have 92 dakota 3.9l and as i was puttin in new coolant temo sensor it snapp off half way do now im lookin at a hollowed out half screw threaded in my coolant block. I dont know if it will even have enough bit if i used dome kind of easy out drill bit and if i do what should i use as well as type of drill like a impact or regular drill and what damage can occur if i drill thrre the switch and it crumbles everywhere and cyclces thru?

 

The damage would possibly be damaged thermostat, damaged water pump, and plugged heater core or radiator.

A full block flush would help to prevent that, even if it did drop off.

But ... "in my coolant block". You mean the one in the intake, or where?

If it's in the intake manifold, possibly remove the intake, drill it, remove it, clean out the hole, rinse out the water passage in the intake, and ... do your plenum gasket while it's off. A win/win IMO.

RwP

 

You can minimize the swarf by using a shop vac to suck it up as you go. Go slow, slow drill speed and use oil to cool the bit. You want to minimize the bit pressure so that you don't have the cutting edge bind up and break the sensor stub. A few bits of drill shaving won't hurt, probably. Use a good quality stud/stub remover to back the wreckage out. You should get a proper sized tap to chase the old threads. And DON'T over torque the sensor next time!