[tszetela]

Has anyone tried to fix a striped screw on a Danner mag-drive pump?
I have a mag 2 that I use externally on my newly rebuilt kalk stirrer that leaks a little because of one screw.
I was thinking about mixing up some Weld on 40, filling the hole a little and putting the screw in it “re-set” the threads.

Has anyone tried this or another method?

 

[eelman]

mag pump

That will work to fix the loose screw, had a friend fix a mag 12 for me. But it may still leak. You also need to check the o-ring.

 

[ryan72]

Won't you be glueing the screw in there then? I know weld on is for plastics, but I think it will stick to the metal enough where if you ever need to take the screw out, you may be unable to. But then again, I don't know of any better way, so it may be your best shot besides replacing it with a little bit larger screw or buying a whole new pump.

 

[eelman]

fixing pump

The idea is to fill the hole with a epoxy and then re-tap the hole with new threads or a self-tapping screw.

 

[E-quality]

Let me get this straight. A screw is stripped and you can't get it out? The threads are stripped? I don't understand. And, where is it leaking from exactly?

 

[tszetela]

The screw is not striped. It is the plastic threads in pump housing that are striped. The screw comes out but will not tighten down enough to seal the inpeller housing to the pump body.
And weld on 40 and most other plastic solvent type glues have very little "stick" to them. They adhear by melting the plastics together, so I don't think that it will stick to the metal.
I would try the real fill and tap method, but I don't have any taps so I was just going to use the screw as a kind of mold.

 

[E-quality]

I wouldn't try to seal it, that would be messy and probably not work right. If you have a drill, got to an automotive or hardware store and get something called "save a thread". I forget the common name for it but save a thread is what it is. It's basically like a metal coil that you put into the screw hole, after you drill it out, and acts as new threads. You may want to ask if it will work in plastic though, I'm not familiar with using it in plastic. You may need to put some "lok-tite" in the hole before the threads to seal it to the plastic. That's my idea, unless you can find someone with a tap and die set, ask around.

 

[eelman]

mag 2

this is beging to sound like too much. Why don't you just buy a new pump?

 

[tszetela]

I would buy a new pump, but we are building a new house and trying to save some cash. ... and I think it will be an easy fix. I was just wondering if any one else had done it before.

 

[greenb]

You could try to just re-tap the hole. You can get a drill/tap combo at home depot for about $10.

OR you can give this a try, I've done this on a lot of projects but never on plastic. If you slide toothpicks into the whole and break them off flush you should be able to screw the screw in and hold it tight. It sounds silly but like I've said I've used this trick a bunch of times.

I've also heard about the metal coil tip before. But I don't know where you'd buy that from.


Just a thought.

Bob

 

[sean]

Hey tim, i wasnt sure where to put this, but i couldnt reply back because of your pm box is full. Just a tip to empty it if you want to keep a lot of your stuff from your inbox. Just go to sent mail, and delete all those mails, because that counts toward the 70. Thanks

 

[tszetela]

Sean, yea I did that this morning after I got the 'your mail box if full message." I always for get to keep my sent box clean. I do the same thing at work too

 

[rmkj]

Tim

Do know what size tap you need?
I can bring one home from work on Monday and we could give it a try.

Rick

 

[Planecrazy]

I don't have a mag drive pump to look at, but it the housing is plastic and the screw is specifically designed for plastic (coarse, deep threads) a tap isn't going to cut it (no pun intended). The best course of action is to take some epoxy putty (live the harvey's you use to glue down coral and fix your tanks) and do as you originally suggested. Fill the hole and mold the epoxy around the screw. You can clamp the housing together while it's drying to keep the epoxy plug from coming out or you can use some vaseline as a release agent on the screw. That way, when the epoxy dries you can loosen and then tighten to the desired torque (of course without destroying the plug you made). If the epoxy putty is too thick, I would also suggest JB weld quick. Good luck!

-Aaron