Best thread sealer for coolant

[dlundblad]

The coolant petcock valve (aluminum) that is in the block on my $500 Kubota garden tractor snapped so I need to drill out what is left, rethread, and replace. The results may or many not be pretty. I have a new valve on order from the dealer. $8.

Should I use teflon paste or possibly Permetex water pump gasket maker? Not really interested in a helicoil at the moment as I don't want to drill an over sized hole into the block.

Thanks and Happy New Year everyone.

 

[Trav]

No need to rethread just drill it almost completely out by up sizing drill bits till its almost to the threads then remove the leftover threads out with a pick or EZ out.
Do not use an EZ out without drilling most of it out, it will snap then you can have a real good time. Use Teflon tape to install it, it will prevent leaks and future seizing.

 

[nthach]

After fixing your threads, I like to use Loctite PST anaerobic thread sealant(Permatex high-temp thread sealant with Teflon) or even Oatey/Hercules white pipe dope with Teflon. The taper of the petcock or pipe fitting is what's doing the actual sealing - sealants or dopes help with microscopic sealing.

 

[dlundblad]

Originally Posted by Trav
No need to rethread just drill it almost completely out by up sizing drill bits till its almost to the threads then remove the leftover threads out with a pick or EZ out.
Do not use an EZ out without drilling most of it out, it will snap then you can have a real good time. Use Teflon tape to install it, it will prevent leaks and future seizing.


Easy Outs scare me. Never had any luck with them.

The hole diameter is either 12 or 13mm I'd guess.

 

[SHOZ]

Easy outs snap becasue of uneven side torque when tightening. If you use a tap handle they work much better than a wrench.

 

[ka9mnx]

Like Trav says. Always worked for me (and on bolts). I stay away from easy outs (they rarely work for me). I always use Teflon tape on pipe threads.

 

[Trav]

You are right to be afraid of EZ outs. Some basic rules of using them are..
If the bolt breaks removing it due to corrosion forget the EZ out using only a small hole in the middle of the bolt, chances are it will break off, this is especially true in aluminum.
Not getting the EZ out deep enough in the broken bolt, if it is only in there a few mm it is a guaranteed break.

Spiral types are the most common and usually cheapest, these are the worst for breaking, they can actually jam the broke piece tighter in the hole. The tapered type is better, only use high quality (more money).
EZ outs can be used successfully on bolts that broke going in, this is common when TTY bolts are reused too many times, using a LH drill bit will get them out most of the time without using the EZ out.

They are also successful when most of the bolt is gone and only a thin portion and the threads themselves remain eg a 13mm bolt drilled out with a 11 or 12mm bit, the remnant will come out easily.
Accurate drilling is essential for easy removal, basically you must make the broken part flat if proud and use a center punch that is exactly in the middle of the broke part and drill straight. You may need to make a jig out of 1/8" plate to attach to surrounding bolts with a bolt tapped into it. Drill through the bolt on a drill press so the drill continues going straight as its going into the broken off piece.

Your broken part should be very easy, it already has a hole going right through, just use the next size up and continue till its almost gone but the threads remain, what remains will come out easily with no rethreading, just chase the junk out of the threads with a tap (if its pipe thread you must use a pipe tap) in that case if the threads look okay I wouldn't bother, if you start cutting new threads it will sink the part deeper and cause problems as pipe taps are slightly tapered.
You can use a Dremel with a small wire cone brush to clean any rust off the threads.

I have had one of these for many years, its the best center punch I have used, it takes a little practice but is more accurate than automatic punches and easier than a hammer and punch.

https://www.amazon.com/Spring-Tools...mp;psc=1&refRID=XP5Z1FM1VQ3GDM7J78MA

 

[dlundblad]

Is this what you mean when you say tapered?

https://protoolwarehouse.com/willia...XqYTK3wIVAS5pCh0mfwRnEAQYByABEgJfT_D_BwE

 

[Trav]

Yes that it.

 

[Trav]

To late to edit. there are other types that work well also, it depends on the size of the bolt and how much depth you have to work with.
The multi LH spline are great for larger bolts but the thin ones snap easy. For smaller sizes the straight spline is much better, most important is the quality, get top shelf or don't get them, cheap ones will leave you with a real mess on your hands.

The Williams you linked to are very good as are the ones from Proto, Snap On (the Williams are the same), old USA Craftsman (Western Forge, Proto, Mayhew, etc) and a few others. I have the Irwin multi spline and Blue Point set with drills and tubes single spline, both are very good as well as the Proto tapered.
Removing broken bolts and rotten fittings is a daily thing for me and always has been so good stuff is a must or nothing would get done. The last thing you want are elcheapos from HF, new Craftsman, Lowes, HD, etc.

A couple of examples of the other types. They all have their uses, know where and on what is the trick but you pick that up fast or shoot me PM if I can help.

 

[dlundblad]

No dice. Bought a #6 tapered style Irwin easy out as well as the spec'd 15/32" bit. It just dug it down to the threads.

Not sure where I went wrong, but should be easy to retap at this point.

 

[Trav]

It looks like there is still threads in there? Did you try a pick on them to see if there are still some in there?

 

[ka9mnx]

Left hand drill bits work good too...

 

[HangFire]

I've had Turbos work on occasion (sockets that go over rounded bolt heads), but I've yet to have an EZ-Out work. The basic problem is they expand the bolt from the inside out, which is the exact opposite of what you want.

LH drill bits have worked very well for me. Usually once I get in deep enough, the remains of the bolt just unscrew themselves. On occasion I've had to drill until there's nothing but threads left (bolt threads and casting threads both), then peel it out and chase the threads.

Center punches have never worked for me, unless the bolt head is still extant. Usually I'm working with a broken off bolt inside the casting. A round mounted stone on the air die grinder to take off the high side, then a small mounted stone to make the center impression. Then I can drill right away with the LH drill bit.

I bought a right angle air drill just for the purpose. Whatever you use should have a keyed chuck, so it doesn't loosen itself in reverse mode with the LH drill bit.

 

[Trav]

If its broken off and a few threads are available just drill a hole for the LH bit through a bolt of the correct size and pitch. Screw it in with a nut, tighten the nut to firm the whole thing up and drill, it will be centered. A lathe is best for drilling the bolt but a drill press works okay as well if you get the bit centered properly.
You don't need a keyed chuck, my drill press has a 3/4 inch keyless chuck and it wont loosen (yes it has reverse for tapping, its direct drive).

 

[dlundblad]

Originally Posted by Trav
It looks like there is still threads in there? Did you try a pick on them to see if there are still some in there?


I was able to pick a few of the rearmost threads, but the front most look either embedded with aluminum or flattened out from the Easy Out. The big cut through what was left of the valve like butter so I think for the most part, the threads made it out alive.