I'm in a real pickle - need advice

mattmor · 20th August 2012, 18:55

I was in the middle of doing a new water pump, thermostat, belt tensioners etc. when I snapped off one of the hex bolts for the water pump. It's #5 on the realOEM diagram which goes in the top hole of the water pump. I came back with the bolt and about 2 threads on the end leaving the rest of the bolt back in the block. Chances are that I over torqued the bolt going back in, but I wasn't giving it much so it could have just been brittle.

I'll probably have to remove whatever is between the water pump and the block where the threads are in the back. (Vanos, timing?) Then use the standard broken bolt removal tricks with a drill bit and easy out. Perhaps, someone with a lot more experience can point me to some of the DIY threads that can help me get to where I need to be and also whatever advice that might be useful when working on this. I'd really appreciate it. I'll post some pics of the broken bolt and point out the area of the engine in question when I get home.

m5 deamon · 20th August 2012, 19:45

did you get the bolt out

mattmor · 20th August 2012, 19:51

Here's some pics of what I'm looking at.

mattmor · 20th August 2012, 19:54

Quote:

Originally Posted by m5 deamon

did you get the bolt out

Only thing left is the threaded part of the bolt that broke off inside. Everything else came out that's in the picture above.

gzig5 · 20th August 2012, 20:02

I would start by getting a good quality 1/8" aircraft drill (usually about 6" long) and wrap electrical tape around the shaft in two places along the shaft to build up the diameter to just under the diameter of the hole through the water pump. This will center the drill bit in the bore and should allow you to start a pilot hole fairly well centered in the remnant of the bolt. All you need is a shallow hole at this point. Then you'll have to remove the pump and see where you go from there. An easy out and some heat applied to the block around the hole may be enough or you may end up drilling it out. I suggest this because getting a hole to start in the middle of a broken bolt can be a challenge.

mattmor · 20th August 2012, 20:25

Quote:

Originally Posted by gzig5

I would start by getting a good quality 1/8" aircraft drill (usually about 6" long) and wrap electrical tape around the shaft in two places along the shaft to build up the diameter to just under the diameter of the hole through the water pump. This will center the drill bit in the bore and should allow you to start a pilot hole fairly well centered in the remnant of the bolt. All you need is a shallow hole at this point. Then you'll have to remove the pump and see where you go from there. An easy out and some heat applied to the block around the hole may be enough or you may end up drilling it out. I suggest this because getting a hole to start in the middle of a broken bolt can be a challenge.

Hell of an idea. Where can I get one of these aircraft bits?

gzig5 · 20th August 2012, 22:11

Ace Hardware or maybe Home Depot usually has long ones in 1/8" or so. Just make sure what ever size you use is less than the minor diameter of the thread so you don't take out too much.

mattmor · 20th August 2012, 22:22

Thanks. Im going to try this out. BMW shop quoted me 35 hours to remove everything so they could get directly to the threads and remove without damaging anything. Thats a last resort for me. They tried to make it seem like I would be crazy trying to get it out myself as its too easy to damage the engine block. Im not so sure.

fmcfad01 · 20th August 2012, 22:30

Quote:

Originally Posted by mattmor

Thanks. Im going to try this out. BMW shop quoted me 35 hours to remove everything so they could get directly to the threads and remove without damaging anything. Thats a last resort for me. They tried to make it seem like I would be crazy trying to get it out myself as its too easy to damage the engine block. Im not so sure.

wow, that's laughable.

rao · 20th August 2012, 22:30

Just take it easy when you are doing this. It is one of those things that is conceptually very easy, but in reality can be quite challenging. Depending on the area around this hole, you should be able to make a repair with a heli-coil if the threads get ruined beyond repair.