After searching, I found a number of good suggestions on how to get the water pump studs out. Followed the advice of the forum (liberal doses of PB Blaster, let it sit, heat with propane torch, tap with hammer) and two of the studs still broke inside of the block. I have the engine out on a stand, so clearance issues aren't a problem. Now, for all of you that have faced this dreaded monster in the past, I need help before I truly screw something up. Here are the options I have available:

1. I have a set of left-handed drill bits and extractors
2. I can take it to my machinist and let him try, no guarantees though
3. I can drill out what's left of the studs and helicoil in some M6x1.0 threads

I would prefer to give it a try myself before bringing the block to my machinist with my head hung low in shame. I've never tried to remove a broken bolt/stud before, but I've done a fair amount of research through the internet on how to do it. Unless I read something wrong, when drilling it is absolutely critical to get the drill perfectly in the center of the stud. Is this correct?

Also, how does one use an extractor? From what I've read, there has to be a small pilot hole drilled first, then the extractor is seated in place by tapping it with a hammer, and then a wrench is used to turn it counter clockwise.

If anyone is near Ft. Belvoir, VA and has some time/experience to lend this weekend, please PM/email. This is the ONLY thing keeping me from finishing the front of the motor.

 

you should heat the block part.. not the stud.. Def give it a try first though.. Then machine shop. Don't drill out until machine shop has a go. That would be my preference.

 

Forget the extractors - you will be pissed if you use them!
The studs are small enough that there is a very good chance that the extractor will brake off - and then you will have a hardened steel part inside a steel stud in an aluminum block....a real pain to drill out!!!

 

"Santa brought me broken water pump studs " - think that was the Grinch..!

 

Thanks for all your help Chris, the block is going to the machinist on Monday for his expert help.

 

A tiny burr bit in a dremel tool was the best method I found for getting them out. Much more finesse than a drill bit. Slowly turn that steel into powder. Once you have a good hole chewed out of the center of the stud, any of the other extraction methods work pretty well. The stud is now weaker thanks to missing all of its guts.

 

The water pump studs are made of pretty soft material and are pretty easy to drill out, especially if the block is alteady out of the car. Just make sure you use new high quality drill bits, and the run a tap through it. You should be able to easily do this yourself if you have the skills to assemble your own engine. Give it a try, its much easier than in looks.

 

Sooooooo many times I've ended up in this scenario...

 

Since I have to take the head to my machinist on Monday anyway, I think I'll just bring the block too. I'm sure that drilling out the broken studs is far from impossible, but I'd like to try and salvage the threads because of the strange thread pitch and the fact I don't have a tap in M6x1.25. Thanks for all of the advice, hopefully this won't slow my rebuild down too much.

 

Instructions for using an extractor:

1 Remove extractor from package
2 Hold extractor firmly between thumb and forefinger with tip pointing down.
3 Gently release extractor while holding 2’ above a trash can.

:-)

In my (very limited) experience the water pump studs are only the first things to break. So far in my build I’ve broken a water pump stud, snapped one of the M8 girdle bolts and stripped an M6 hole for the balance shaft covers. I snapped an extractor trying to remove the water pump stud, and spent a couple of hours grinding it out with a diamond tipped dremel. Definitely wont make that mistake again.

I ended up drilling and helicoiling all three holes. And I bet I’ll have more to do before I’m done putting everything back together. In my mind it makes sense to learn how to install a helicoil, otherwise you’ll spend a lot of time and money going back and forth to your machinist. It's not hard to do and there are a few tricks that can make it cleaner and easier to get right.

 

I took the same broken studs to a machine shop and they screwed it up pretty bad -- had to re-weld and resurface it. Since then I've always done them myself. Use cobalt drill bits, starting very small and work your way up. Never use an extractor on those studs -- they will snap off and make things much worse. If the drill bit hits the original block threads, just helicoil the hole once the stud is out--threads will be better than new that way!

 

I second that, i had a machine shop screw up a 3.0l block once, do it yourself, take Tom's advice.

 

Yep, every new problem is just another chance to buy more tools in disguise!

The other lesson is don’t use a machine shop full of idiots!!

 

well, the shop that I used it was a Mexican guy, do you thing that has anything to do with him messing up?

 

Did he think it was a lawn mower engine?!?