Thanks to all who gave me advice after I broke a water pump bolt and managed to drill the wrong darn hole with a 7/64 bit. I then snapped off the tip of an extractor because, ummm, there was no bolt in the hole in the first place.

The hole on the block that I drilled is exactly the size of the bolt and stud holes, but is within the perimeter of the pump gasket and housing. The hole was OEM - I bought the car new and removed the original pump after 156,000 miles. Haynes shows a picture, but doesn't say anything about the hole. I can't find it in Bentley at all.

I drilled metal for a couple minutes, and then the drill hit nothing but air. I only drilled in less than 1/2". Your advice along with a visit to the dealer and a Volvo independent with the attached digital photo has put my mind at ease - I likely drilled into the water jacket and not the cylinder wall.

Neither mechanic knew for certain what the hole was for. It is circled in yellow in the attached picture. If anyone has a water pump off, can you tell me whether yours is solid, in other words not completely through to the water jacket - or a thruway? One post and the independent suggested it was solid, and was intended to reduce cavitation. Anyone know for sure?

Thanks for the help. Yes, I screw up on occasion. But you all sure help me through the stupidity. And I never do the same blunder twice!

Dave
91 240 Original Owner - haven't killed it yet!