Sheared off pipe nipple in block

I have twin American Diesel 135s. On the port side of one engine, there is a line to send coolant to the water heater. There is a 1/2" brass threaded pipe nipple that has sheared off in the block.
I am going to attempt (for my first time) to extract the sheared off piece still in the block with an easy-out.
I have some questions.

Is there any advice I should know before attempting the extraction.
It seems straight forward but I don't want to mess this up.

Should I go back with a brass nipple? Seems like the weight of the fittings and valve hanging on a brass nipple from a vibrating engine is not a good idea.
Perhaps a stainless steel nipple would be better but is there concern with different metals being used in this application.

If you have access to a small torch putting the remaining piece of the brass nipple through a few heat cycles may help the extraction. Breaks loose any remaining pipe dope etc.

SS nipple shouldn't be a concern in this case, they are becoming quite popular in the plumbing industry now due to the high cost of brass. Nobility of the metals is reasonably similar.

Why did it shear off, was it hit or stepped on and broke or was it stuck in place and broke off while trying to unscrew it? A good application and soak in Kroil or other penetrant before the easy out won't hurt.

I think it sheared from time and vibrations. Fortunately I discovered it before it completely let go under way. I would feel more comfortable with a s.s.nipple. It seems like it would be sturdier.
I don't have a torch but sounds like something I should add to the "box".

What type of sealant or dope should I use when threading in the new nipple?

Use the twisted flute style of easy out. I've had very good luck using them for the very same thing.

Easy out and brass are not a good mix because the brass is soft and may just tighten in the hole but its worth a go. Seen that the hole is 1/2 inch grind down the end of a hacksaw blade so it fits in the hole then cut down the brass to metal in the block .Repeat this at 90 degrees then try to tap out the remaining brass with a 1/4" chisel . In both cases give a good squirt with pipe freeze it may just shrink the brass enough to help

I was wondering if a twisted tapered easy out would expand the brass locking it further into place.
I will try it first and see what happens. If that fails then cutting will be plan B.
Any ideas on how to keep pieces from falling inside the block (sounds like a very bad thing).
Still wondering what is best to seal the new nipple in the block and fitting.

Steveg353 said:

I was wondering if a twisted tapered easy out would expand the brass locking it further into place.
I will try it first and see what happens. If that fails then cutting will be plan B.
Any ideas on how to keep pieces from falling inside the block (sounds like a very bad thing).
Still wondering what is best to seal the new nipple in the block and fitting.

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Use plenty of sticky grease on the hacksaw blade. Cut wipe cut wipe cut wipe And or attach a length of 1/2 plastic tube to your shop vac

Leak Lock

Highside Chemicals Inc. manufacturers Leak Lock and Leak Lock Gold.

99 cent toilet wax gasket from any hardware store can be used to catch chips. Put the rest of the wax into a zip lock bag and make it part of your emergency kit for dealing with leaks.

Teflon tape is my preferred thread treatment but any pipe dope will work fine too.

Another thought what is the ID measurement of the brass fitting ?? You maybe able to just tap a smaller dia thread into the brass and use a smaller pipe ???

"What type of sealant or dope should I use when threading in the new nipple?"

Yes to teflon tape.

"Any ideas on how to keep pieces from falling inside the block (sounds like a very bad thing)."

When cutting a hacksaw grove in the brass pipe you will try to just cut down till touching the block threads.

This means a portion of the brass will still be intact between the threads.

Brass is soft so when taping it loose you will need to brake the threaded portion.

No big deal, and as you will be prying , chiseling from the outside , as it comes loose it will still be connected further in.

A good set of needle nose should allow you to wiggle it till it brakes free , and not go inside.

Brass as a rerplacement should be fine , just dont step on it.

A 1/2 pipe tap is not expensive and will clean up the block threads.

Replace it with a steel hydraulic nipple. It will be thicker walled and won't fail from vibration.

Gasoila or Mega lock are good sealants which you can get at a plumber supply house. Stay away from dope you can buy at big box stores. I'd give it a wrap or two with tape, then use dope. Don't rely on tape alone.

Try the spiral easy out for sized for pipe. You might have to use some heat. Heat the area around the fitting and not the fitting. Don't be afraid to get the block hot...preferably a little color. Let it cool and heat again, then try to remove while the block is hot. Give it a few lite taps with a hammer to set the tool and give it a try. An extractor of that size has some mass to it, but they are brittle. Be careful using too much muscle and snapping the extractor in the nipple and creating another project.

Another more expensive option would be to try a left handed drill bit. Can be a bit more tricky, but it works.

Lastly, drill it out enough where you can dig out what remains of the threads and run a pipe tap into the bore to clean it up. Harbor freight sells a decent pipe tap set for not much money.

Steel or stainless would be a good choice for replacement. Plumbing supply stores carry stainless. McMaster Carr sells good fittings and decent tools, so you could all you need including tools and fittings, shipped to your door in a couple of days and not have deal with running around for mostly junk sold at franchise type parts stores.

Conall

I removed a broken off cast iron 1/4 inch plug.
I drilled a hole in plug.
Kept drilling bigger, centered holes.
Got it drilled till barely see the threads in the block.
Then sprayed in rust buster.
And ran in 1/4 pipe tap. Cleared the remaining threads, perfect.
Tapered plugs are well tapered, so even if the hole got damaged a little, running in a tapered tap will fix what you have. If the old pipe or plug is mostly gone, then running in a tap will displace the greatly weakened left over plug or pipe and not hurt the original block threads.

For sealers simply permatex #2 non hardening, buy at auto store, or silicone gasket maker made for engines will seal fine. Mechanics do it all the time.

I have a torch and other idea is braze or silver braze smaller brass pipe to broken off pipe, then it will turn out with a wrench.
Use a wet vac, etc, to suck on the hole, may help get out metal fragments.

Also flush engine with a hose the coolant. so that water comes out that hole.

You are correct that vibration of diesels causes many failueres of pipes attached to the block. Very short or flexible connections are much better.


Before using an easy out measure the depth of the hole to make sure the easy out is not trying to screw itself into the innards. It does not take much pressure for a screw to punch some castings.


Sawing the stub has worked for me just be careful to not cut the threads. I saw part way then using a small round back cold chisel gradually tap the pieces out. Some saw filings in the cooling system are no big deal.

Heat will expand the broken fitting in the hole. Not what you want. The freezing spray is a much better idea. Auto parts stores have a product that freezes and has a penetrating lubricant in one product. It works well but you need to use more than you would normally use to have the cooling (and shrinking) effect.


If you go to a well stocked home center or a plumbing supply house you can buy an "internal pipe wrench". It fits inside the pipe and expands to grip the pipe when you turn it. I have one and have used it in situations such as you are describing.





HDX Internal Pipe Wrench Set-HDX150 - The Home Depot


As for sealing the new fitting, Teflon thread sealing tape or pipe dope will work. There's nothing to gain from using both. The dope is not going to stick to the tape. If you need electrical continuity (you don't in this case) Teflon tape is an insulator, pipe dope is the product to use.

If you go to a well stocked home center or a plumbing supply house you can buy an "internal pipe wrench". It fits inside the pipe and expands to grip the pipe when you turn it. I have one and have used it in situations such as you are describing.

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We have a winner! good job, I forgot about that tool.

Yes to the notch cut with a hacksaw. One notch and try the easy out or several and pick out. Try one then the other.

Either heat cycles (to loosen corrosion grip but brass really shouldn't have much in a coolant hose) or cold to shrink and losen...either will work...in this application I like the cold but if heat is handy, start with that.

The internal pipe wrench is nice too if easy to get and not too much $$$$.

gaston said:

Easy out and brass are not a good mix because the brass is soft and may just tighten in the hole but its worth a go. Seen that the hole is 1/2 inch grind down the end of a hacksaw blade so it fits in the hole then cut down the brass to metal in the block .Repeat this at 90 degrees then try to tap out the remaining brass with a 1/4" chisel . In both cases give a good squirt with pipe freeze it may just shrink the brass enough to help

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+1

Can't think of anything worse than brass for this job, except perhaps aluminum

Amazon sells the Cobra Pipe Nipple Extractor set. This works well if there is very little space to swing a wrench and is designed for pipe nipple problems. Wish you good luck with your project.

You don't want a valve cantilevered out on a pipe nipple from an engine block. Vibes will fatigue the nipple right at the thread roots. Especially brass. Get a hydraulic nipple, steel.

How very lucky you are to be able to see, let alone get at the nipple!

Replace the others, too, if they're brass. Steel or stainless steel would be preferable to brass. Even though there is anti-corrosion stuff in the coolant, dissimilar metals are undesirable (though copper, brass, steel and iron coexist in residential hot water heating systems). Steel nipples will fail from fatigue, if the loads and vibrations are high enough.

I had the 1 1/4" exhaust riser nipple break off of the manifold of the Yanmar 3GM30 in our sailboat. Happily, the fitting at the end of the manifold came off with a pair of bolts and a gasket and I was able to take the piece ashore, put it in a vise and saw the requisite grooves to peel the bit out. I'll never tell that I simply reinstalled the broken nipple and it's been trouble-free for the last 10 years/1000 hours.

Internal nipple extractor. It is the best for this. Don't ask me how I know.

bilge53 said:

Internal nipple extractor. It is the best for this. Don't ask me how I know.

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mmmm ! .... nah ! I won't say it

I knew somebody's mind would go there.

bilge53 said:

I knew somebody's mind would go there.

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Yours too apparently

http://www.amazon.com/Wheeler-Rex-87050-Nipple-Chuck/dp/B002MRO5MS/ref=pd_sim_sbs_469_2?ie=UTF8&dpID=11yVvmcJduL&dpSrc=sims&preST=_AC_UL160_SR160%2C160_&refRID=15NZER7SV0EMDYYXNZMB

I have yet to run into a corroded or broken nipple that wont extract with this tool.

And I am not a big fan of the stainless nipples. Stainless is very hard and brittle. If absolute care is not taken, threads can break off and the nipple will damage the female threads it is seated in. It can also get stuck when threads break off and lodge in the joint. I would rather have softer material on the male fitting (nipple side). My opinion is to just get another brass one. How long did the existing one last?

Stainless is very soft and has low sheer personally I hate the stuff its over used and often used as a cheaper way of manufacturing a product because of its makeup .Stainless into anything but stainless is a problem waiting to happen.
When a design engineer is developing a new product a lot of consideration is placed on materials that will be used in the manufacture of a product. Consideration is taken in choosing sacrificial materials that can be used to assist maintenance at one stage in the products life. I'd say brass was used in this situation as it for-filled the engineers specs .Brass and cast iron are a good combination in engine design and both have been used together for many years so just stick to OEM they do know what they are doing .