Broken head on thermostat housing bolt.

[ellisjay2]

When I replaced my water pump last summer I torqued down on the thermostat housing bolts and broke the head on one, and the other half of the shaft is stuck in the bolt hole. I plan on pulling my water pump again soon due to a low brand I selected from advance auto parts, (bearings are starting to squeal, but in order to remove the thermostat I must figure out how to remove the broken stud left in the bolt hole.......the only thing I can think of would be some kind of thin drill bit and trying to screw both pieces out???

[Yurick]

You are warm. You will need to drill a hole in the broken bolt and then tap it out with a left-handed thread tap.

[Jeron]

Yes there are many bolt out kits at hardware store. Sears is a good price vs quality store.

Are you sure the pump bearing is the current problem?

[ellisjay2]

Thats what a BMW mechanic told me, plus I used a low brand name part.

[Jeron]

There are lots of bearings that can squeal and would be more noticeable than the water pump. The more common ones are the tensioner pulleys and the deflector pulley.

Also water pumps are only $50 so I dont know what low brand part you bought but I didnt realize there were and cheaply made pumps out there.