Have radiator seem leak so replacing it and thermostat too. I was putting the thermostat housing back on and snapped one of the bolts off. Top third of bolt broke off. Looks like this is the water pump so I am thinking probably easiest to remove water pump and easy-out the bolt or retap with larger bolt. Any thoughts, advice, or suggestions?

Is there enough bolt sticking out (with the thermostat housing removed) to get a pair of vice grips around to turn it out? I'd try that first. But you need to check those threads, if they are damaged a new bolt may go in and strip the threads out, then you'll be right back in the same boat. If you have a tap kit this is a good time to use it.

I haven't removed the other bolt and housing yet (called it a night and will check it tomorrow) but guessing there won't be enough for vise-grips. Good point about just tapping new hole.

If it's an old pump just replace it. If it's new just soak it with PB Blaster and use standard extraction methods to remove it. It will depend on whether or not it was simply corroded or cross-threaded which method you might want to use.

How many miles on this car? Has the water pump ever been replaced? Timing belt?

dont he-man on those little bolts. use a 1/4 drive tool. the torque is measured in inch-pounds. just hand tight, then snug about 1/8 turn.

 

same for the water pump and oil pump bolts. we got tiny bolts threaded into aluminum. all too often i see 'hillbilly torque' ruin parts on these cars that are serviced by old-timers whho are used to torquing coarse threads into iron

Water pump and timing belts done less than 10k ago when I had head gaskets done. I think I just over-torqued it - my torque wrench calibration must be off. Usually I don't even bother with torque wrench. Oh well. lesson learned.

 

Hopefully a little penetrating oil and I can extract it. Otherwise drill and re-tap. Really don't want to replace an almost new water pump. And hopefully can get this done without removing timing belt and water pump.

you might be able to put a nut at the other end of the hole. I have done this, on the frontmost bolt

"you might be able to put a nut at the other end of the hole. I have done this, on the frontmost bolt"

 

 

What do you mean?

on the backside of the flange. a longer bolt would go all the way through

If the threads in the WP housing are crossed or stripped out you can drill it out and run a longer bolt through with a nut on the top side of the housing.

I pulled the housing back off, sprayed some Kroil from the top to loosen the bolt up and was able to back it out with my fingers. I also saw that these bolts are designed to shear right wear it did, since there is a taper to the threads. I suspect I need to source these from a dealer parts counter?

I got a few from the hardware store to replace the rusty ones on my wagon. Anything grade 5 or better should work fine as long as you get something with an anti-corrosion coating such as zinc.

Stainless steel is not as good of an idea as it sounds, so stay away from that.

metric m6x1.00 thread, you can find them anywhere.

The tstat housing bolts are only torqued to something like 6ft/lbs. You don't need any special hardware.

The tstat housing bolts are only torqued to something like 6ft/lbs. You don't need any special hardware.

 

You need enough strength in the shaft of the bolt to overcome any rust/corrosion on the threads when trying to remove it. If you use the cheapest hardware you can get, you end up with a broken bolt.

Stainless steel is not as good of an idea as it sounds, so stay away from that.

 

You need enough strength in the shaft of the bolt to overcome any rust/corrosion on the threads when trying to remove it. If you use the cheapest hardware you can get, you end up with a broken bolt.

 

I agree on both counts. The stainless hardware you usually find in hardware stores is 18-8 stainless which is really weak stuff. Stronger stainless alloys are prohibitively expensive to stock at your neighborhood hardware.

 

As Fairtax mentioned, anything with a corrosion resistant coating will do, remember that every other bolt on your car has just that. Some antisieze doesn't hurt either.

 

Will-

I agree on both counts. The stainless hardware you usually find in hardware stores is 18-8 stainless which is really weak stuff. Stronger stainless alloys are prohibitively expensive to stock at your neighborhood hardware.

Will-

 

This may be true (i'm no metalurgist), but there is also the problem of galvanic corrosion of the aluminum when stainless and bare aluminum come in contact. This will rather quickly cause the bolts to seize and will deteriorate the threads in the aluminum. Makes it a royal pain to take apart later on.

It may only be certain grades of stainless, I'm not sure, but I see it all the time.