Hello, I was swapping out my thermostat and broke a bolt in half putting it back in. I had my torque wrench set at 21 ft. lbs. which is what my Haynes manual specifies. Will I be able to drill out this bolt and clean out the threads without damaging the water pump? Hopefully I didn't F up my weekend.

 

All you need to do is by a small drill bit and drill right in the center of the bolt, then buy a bolt extractor which you ratchet into the bolt and it unscrews it. Actually buy the bolt extractor first then it will say which size hole to drill. Go to sears and pick up an extrator its just a bit and is cheap.

 

I doubt that the tq on those bolts is 21 ft.lbs. That seems very high for those little bolts.

 

Well, I would suggest not using a torque wrench on something like that. Tis better to just tighten the thing up using the appropriate wrench which should provide you with adequate torque---i.e. if you are not a girly man. Anyway, if you can get a pair of vise grips on bolt, you should be able to get it out. If not, you can try to use a small angled chisel to back it out enough to use the grips. Otherwise, what the other guy said: drill and extract. JMHO

 

Thanks for the replys. The bolt is broke off flush with the water pump so I'm thinking the bolt extractor is going to be the way to go. I thought 21 ft. lbs was a little too much, hopefully I can get it unscrewed out and put in a new bolt.

 

Well if it is broke off flush with the pump, can't you get at it if you remove the pump?

 

The torque spec is 89 in lb/10 Nm which is about 7 1/2 lb ft.

 

Ya if I remember when I tighten those I just go hand tight

 

Never mind: For some reason I was thinking the bolt was a water pump bolt instead of the T-Stat housing bolt.

 

I think I'll just snug them down next time and not put the wood to them. I still don't know why the Haynes manual says 21 ft lbs. I hope to get the broken one extracted tonight and get a new one in there and put the car back on the road.

 

It's wrong because it was printed wrong in many manuals.

Try using a punch and a hammer and tapping around the edge in a counter-clockwise arc. You may get it going enough to get it out. If you have to drill, use a reverse rotation bit and it may just spin itself out.

 

Yeah when a bolt broke off flush w/ the block on my starter, we started drilling it to put the extrator in and the drill itself started moving it enough to the point where we could get it out.