Thread: URGENT: cooling system bleeding screw missing

Any small bolt that fits will do, however why has it gone?
Is the thread stripped?
You could get some 2 pack epoxy and screw a small bolt in coated with epoxy..
They tend to strip the thread if you undo them anyway and the thread falls into the hose. Ask me how I know.

Regards Philip A

Get a new one sent in by Mario via the post
Or as stated before just find a suitable bolt and use sikoflex or araldite on it as a TEMPORARY Fix.

Hopefully it hasn't snapped inside the hose and gone through the cooling system.

I have no idea what services are available in Agnes Waters, but if finding a suitable bolt to fit, as an emergency you can cobble up a hack that I've had work for brother.

You need what's called a 'wallmate'. This thing is a plaster screw that screws into plaster and allows you to hand stuff on walls. Has a very coarse thread and a wide flange area.
Note that if you do try this 'hack', you need the cheaper plastic wallmate, not the diecast aluminium types! the plastic helps to create the seal.
Other thing you also need is a small wood screw.
If you have a bare hole(ie. not snapped bleed screw) in the hose, before you screw in the plastic wallmate you need to cut the pointy tip off leaving just the thread of the wallmate.
Once you screw this in, then you screw the wood screw into the wallmate. The wallmate is hollow, and will leak if no wood screw.
Just whatever you do, don't use a metal(or self drilling) screw into the wallmate. The drilling head on a self drilling screw will damage the wallmate and will not seal.
Wallmate in as far as you can screw it(you need a philips screwdriver), and then screw not too hard into the wallmate, you will feel it come to a stop. Don't over tighten the screw.
Don't use countersunk screw head, just a standard cheapie dome head screw. I think about 6g(size of screw)... maybe it was 4g .. can't remember. Not too loose but not too oversize.
The threadpitch of the wallmate is just about perfect fit for the thickness of the hose where the bleeder screw fits, so it seals well, and is quite strong.

Note that you will need to bleed again as air will have got into the cooling system. When you undo the screw in the wallmate, the wallmate will come loose, not the screw. No problem, just don't over do it.
Just undo enough so that air stops escaping and just water under pressure comes out nicely. Tighten the wallmate again, it will seal.

When you're stuck at 9PM on a Sunday night and you have to keep going, you do what you need too to keep going!
Brother ran with this for months, before he finally got his silicon hoses. No problems.

Obviously you want to use a more appropriate bolt that will work, but the above works if you have no other options.

I've never been to any hardware store that doesn't sell wallmates, so as an emergency you should be able get something going.

Originally Posted by marcschepp

bleeding screw

Chewing gum and lots of tape. Ball bearing and tape.

If thread stripped then self tapper if large enough available, plus epoxy. Rights sized screw might be in cabin somewhere.

Maybe a plastic trim pin from somewhere in vehicle, pushed into hole and taped.

If really desperate then try tubeless tire plug, just enough inserted to stop the leak, maybe. Pressure only a couple of atmospheres in cooling systems I believe.

Hardware store anywhere around? Larger plug used to seal holes in polypipe when you pull the sprinkler barb.

Any smooth tapered object that can be inserted and held by tape.

If the hose wall is stiff enough, then a pipe clamp or wire over rubber patch and epoxy.