To get one of the water pump bolts out, I tightened two nuts against each other. Then I tapped them with a hammer while turning the first nut CCW. Finally the bolt came out, but I don't think there's much left of the block threads.

While I was trying to get the two nuts on the buggered up bolt threads, one fell into the water jacket on the passenger side. It's an M6x1.0 nut that's 10mm on the outside. Is this a serious engine disassembly required problem? I really hope not because I don't have the money, workspace, or tools to undertake such a project.

The water pump I got from 928 Specialists has a cast iron impeller if that makes a difference in the danger of the nut being in there.

 

Magnet on a string?

(Won't help with the nut behind the wheel, though; har, har. )

 

Pick up the engine and shake vigirously until it falls out.

 

I thought about that, but it's a tight space and don't want two foreign objects floating around in there.

 

I would certainly make some very serious efforts to get it out! Potential problems include sucking it into the water pump impeller with possibly disasterous results.

The "magnet on a string" suggestion is good, and I would also try using a magnet on a wire. Get one of the tiny "super magnets" and use epoxy to glue it to the string and/or wire.

 

Gee, why didn't I think of that?

 

Where would one get a tiny super magnet?

 

Wood working shops sell them. Like Woodcraft or Rockler. They are sometimes called "Rare Earth Magnets"

 

If you can't see the nut and can't get it with a telescoping magnet (available at Sears) maybe you could open up the drain plugs and "backflush" with a garden hose by either first putting the hose into the drain plug and then maybe into the top of the engine block. Check out the schematic of the coolant flow before proceeding so you can determine the best way to flush it out – with water pump off and engine off! A lot will depend on how much water pressure you can generate.

 

I had a similar problem on my 944 S2 when I removed a rear hose attachment on the head. I got it out with a high power industrial vacuum, those that can also suck water out of sinks e.g.

Seal everything else as good as possible and try it, worked like a charm for me

Where did it exaxctly happen? Pictures???

 

If the shop vac doesn't work be itself, try duct taping some heater hose (or whatever you can find that's small enough to fit in the hole the nut fell into), and probe around until you find it.

 

Note to self: Plug the holes first when woking on an engine (when possible) to prevent this from happening to me.

 

I like the idea of a strong vacuum. Flushing with water would make me nervous that the nut might actually get washed deeper into the engine.

 

As I recall the coolant flow is into the block at the two ports and the pump is sucking on the thermostat housing and only would see the nut IF BIG IF it passed all the way through the block up into a cylinder head and into the thermostat housing before being eaten by the pump. So if your lost nut fell into one of the water jacket it would have a long and difficult journey especially for something which does not float to ever get into the pump.Odds are it will simply drop down near the bottom of the cylinder like a rock in a river bed.

 

It did fall down one of the very flat side areas. I got a small O-shaped magnet and a strong magnet on a stiff wire. The O had too large of an OD to make the turn a little below the hole. The one on the stiff wire is too thick to make it past the same point. The one on the stiff wire is quite strong for its size. If the nut was within an inch or maybe two inches, it would've grabbed it.

Looking at my new WP Jim's recollection of coolant flow seems to be accurate. Does anybody know for sure what the coolant flow is?

edited to add: Andrew, the hole was plugged with a paper towel, which fell out when I pulled the wrench holding the two nuts away. The nut actually bounced off the paper towel and into the hole.