As I was completing installation of a new water pump the bolt to the immediate right of the top outlet port (the one that goes into the head) snapped off. I removed the pump and found a stub of the bolt left. Tried vice grips but it wouldn't budge. I then bolted on one of the 6 mm thread nuts that are associated with these bolts, however I have no welding equipment so I couldn't spot weld the two together and hopefully back the remainder of the bolt out of the hole in the block. Instead, I tried to used the bolt as a guide to drill down the center of the bolt with a 5/64 drill and insert a 1/4 screw remover. I was unable to get the bolt dead center and instead ended up on the right side of the thread inside of the bolt. The extractor wouldn't screw in so I went to Sears and bought one of their new bolt extractor sets, also I tried the Elise tap on extractor but it didn't have enough of the remain bolt to grasp, so I began to drill in reverse, attempting now to hit the center of the bolt. Instead the drill portion of the extracting tool kept on tracking and eventually I reduced the bolt's remaining stud to the block surface and tried again with a punch to set it at center. Again more reverse drilling, but when the tool finally caught it just couldn't move the remain bolt out of the hole, but made a great hole to the right side of the original bolt tap.

Now what should I do?

Other than pulling the head and eventually the entire engine block out of the car and sending into a machine shop to be filled, milled, and drilled? I have a metric tap for the bolt and can try to drill out a hole where the original one was using the gasket as a template for the holes location. If I do this will I have enough material left in the head for a retreading, or do I have to go to a larger size bolt say for a 7mm nut or 8 mm nut? Or should I fork over the $40 and buy the helicoil set for the bolt? If so, does anyone know where I can get a helicoil set for less than $40? Also has anyone ever done a helicoli installation??? I've been lucky to remove broken bolts before, except for the first time I tried to do a valve adjustment to my mother's '61 Ford Galaxie (292) when I broke one of the tappet adjustment bolts and couldn't get the old one out by trying vice grips to move it. Instead, an embarassing trip to the Ford dealer resulted in a fix. I was only fourteen at the time, so I racked the episode up to experience and went on, but now I'm fifty-four and I am going to rack this episode up to the early onset of senality! Any suggestions would be greatly appeciated, including, but not limited to geting some really strong pumbler's glue and substituting that for the bolt. Heck if I can get the pump to function for another 100,000 miles the car, which has 189,000 miles on it, should be ready for rings and I can justify pulling the engine and having a machine shop fix the problem ? Or should I just RnR it now and send the whole engine to the machine shop to resolve the problem?

Ouch! I wonder if there is some correlation of 4 here? 14 and 54? Hmmm...

Since the hole is now off center.. a heli-coil is not a option.

If I was going to try this, this is what I would try to do.... It would be easier so long as I understand correctly that the bad hole is on the head to remove the head, but you might pull this off if your slick...

Clean the area well, very well... Drill and tap to the next size bolt up, and no deeper than the original!! A blind tap would help alot after you have threaded to as far as a regular tap can go.

Guesstimate the off set of the now new hole to the water pump hole, With new bolt that will be part of the head placed in a vise drill it which will end up offset probably. Drill it out for the correct size bolt, and drill deeper than you need by 1/4 inch or 8mm...... Thread that for the correct bolt now, and then cut the cap end off close to the correct length.

With everthing spotless, place a nut on the correct bolt, and wind it into the stud you made.

Wind that in turn into the head, and release the nut, and remove the correct bolt. Place the pump in place and see how baddly the stud you made lines up.

Adjust the now blind hole threaded stud to line up as best you can. Mark it and the head with a scribe so you can line it up again.

If need be open the bolt hole in the water pump as needed with care... Try fit this once more to be sure....Besure you place it correctly, and be sure there is no protrusion, and if there is hand file it smooth...

Remove everything and with Loctite brand stud mount glue on you home made stud install it for the last time. Be sure you place it correctly, and be sure there is no protrusion, and install the pump. Leave the problem bolt loose so the stud and bearing mount glue can harden. DO NOT glue the proper bolt, only the stud you made to the head!!!!!!

When the alotted drying time has passed, then snug the correct bolt and warm up the engine a little bit, looking for leaks..

Shut the engine down and allow more time for the cure, as I find the loctite can soften with heating... When the engine has cooled again snug the pump bolts once again and drive the car....

I hope this makes sence to you, and that it helps.... Mac

Yep, it sure does. Thanks for the advice. One thing, I can see the remaining thread to the left of the hole I drilled. The right side of the hole I drilled is perfectly in line with the gaskets hole and the waterpump's. I check this by taking some paint and putting it on the end of the 6mm bolt and placing it in the waterpump's hole, I had bolted up the pump without the gasket to the block. When I removed the pump I found the paint stained only on the left side of the hole. I then put on the new gasket from Volvo and sighted it, and it lined up okay on the right, but had metal on the left. Since the metal on the left is of a different color than the block's and is jagged I suspect its the remainant of the bolt? I'm going to try a round X-acto file first and see if I can easily reduce the remaining metal to the left side of the drill hole. If it's stubborn I think I'll breakdown and buy a new Dremel tool -- my old one has gone missing. So with the Dremel I'll play dentist removing the cavity (bolt remainant) from the tooth (the hole in the block). After removing the remaining metal some locals advise that I try a thread renewer on the hole? Well if they're not too expensive from the Snap-on truck I get a 6.0 m x 1.0 and give it a try. Otherwise, I've already bought the 8.0m x 1.0 from a local jobber for $4.00, and have gotten the cutting oil from a local heating and a/c jobber. All I have to do is get the tool to hold the tape and a larger bolt from my neighborhood NAPA store which has a set of bolts and nuts leftover from when they were an independent and slap it in there.
I've already got loctite, both red and blue. Which one is called for in this calamity?

Um probably red..... Stud and bearing mount.. I don't know if there are more than one red as in liquid.. I know many tubes are red in color.. They have a number on the tube, and I would have a look and at the card the stuff comes in.

A dental pick might help to get the left over bolt threads out, and by all means save the original threads if you can.....

You said large hole and I took it as Moon Crater. I have seen this sort of thing a lot on Air Cooled VW engine at the exhaust studs... And the craters there were mapable.....

I am unaware of any 6mm insert, but I see no reason why there is not such a thing, and if it will line up with in reason use it.

Just be sure the pump lines up before you add gaskets and goo..... You can alter the bolt hole some what for any angle the bolt is not forced to be on, if not dead straight.

Once you know it will work, and make a final install, I would put a dab of anti seize on that bolt for sure. You don't need it to seize to the insert. Another failed bolt here and your gonna be in deeper kimshee than you are now.. But you know that, and don't need me to tell ya..

I think those bolts are torqued to 10 ft lbs and maybe 8, and so are over snugged very easy as you found out. You might consider a better grade bolt as well, with the idea it will be harder to shear.

Kinda almost like having a tiny boat eh? Just a hole to pour $$$ into huh?

I have been checking each day to see if you replied, and am interested in doing so to see how things turn out. I am a x tech, and so have forgotten much in time. I came seeking certain info, and find this place a great help, and hope to be a help when I can... So I wish you and your bolt hole well, and hope you have it fixed soon... Mac