# Broken brass/bronze fitting. I'm stuck...



## RobGallagher (Aug 22, 2001)

On the fuel pump side of my Yanmar 2gm20f there are two valves (or petcocks) for draining the antifreeze.
The lower one was leaking. I attempted to remove it so I could replace it.

Of course you know what happened next, I broke the threaded end off in the block.

Tried an easy out but it won't budge.

Wanting to sail and needing to motor out, I did try putting a self taping screw in with some epoxy and it did not leak, though I didn't run the engine up to full temp.

I have not yet tried heat because the fuel pump and lines are right next to it. I'm afraid of damaging something with a torch and I'm not sure it will help anyway.

The fitting was brass or bronze pipe thread. Any suggestions?


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## travlin-easy (Dec 24, 2010)

What I would do is to drill it out as carefully as possible, trying to stay within the confines of the threads. Then, using a tapered tap, retap the opening to the original thread size. It's a bit tricky and tedious but I have resorted to that on my older A4 and was successful on three occasions with water pump bolts that snapped off flush with the block.

Good Luck,

Gary


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## RobGallagher (Aug 22, 2001)

I should have mentioned, there is very little room to work on the side of the engine.


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## CalebD (Jan 11, 2008)

Clean it out well. Plug it with JB Weld. Forget it and go sailing.


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## SchockT (May 21, 2012)

Well if you are afraid to heat the area around the fitting, you could try freezing the fitting with liquid nitrogen before trying the easy out again. Just pick up a wart removal kit from the drug store. It's worth a shot!


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## dacap06 (Feb 2, 2008)

Have you tried a screw/bolt extractor? Extractors have reverse, tapered threads and are no larger than a tap, so it might be small enough to fit in your tight working area. Normally you would drill a hole in the screw/bolt and then thread the extractor into it. Since you already have a hole in the remnant, you are already half way there. Pick the extractor that's the right size for the hole you already have.

If the material is brass, it may be a little soft for an extractor to work but if it is bronze, it might. If I were in your shoes, I'd soak the area with PBlaster for a while in the hope that it soaks into the bimetallic corrosion area, then try the extractor.

If the extractor does not work you can then do the drill out routine others mentioned earlier.

Good luck, Rob!

Tom


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## RobGallagher (Aug 22, 2001)

@ Caleb, I am considering a fix like that, but, it's the part that drains the old coolant so it would limit my ability to maintain the fresh water side properly (or I could just remove a hose someplace I guess 

@ Schock, I'll give it a shot!

@ Dacap, I have tried the threaded extractor, it's in tight but I can't get the broken bits to back out no matter how hard I pull. I feel I'm just going to break off the extractor.

I'm gonna try Kroil or PBlaster for a few days, then the liquid nitrogen 

I did speak to a machinist. He said that the dissimilar metals have probably bonded. The only way to get it out was lots of heat, to drill it or make the hole big enough to get a tiny metal saw in and cut it out (probably take hours or days), or drill and re-tap. He did say to try PBlaster but that it probably won't be able to get in there because of the bonding.

The good news is that the extractor ("eazy out") has sealed the hole and does not appear to be leaking any antifreeze....lol


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## deniseO30 (Nov 27, 2006)

You should be able to nick the brass with small metal cutting blade from a jig saw. then carefully pry the brass inward. (almost the same as replacing a cutless bearing but much smaller of course. Plumbers and pipe fitters do this often with broken pipes. Warning, the thread may be metric! Get a new drain from yanmar. You could maybe even find a large self tapping bolt with rubber and metal washers to seal it. there used to be something like that available at plumbing supply houses.


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## RobGallagher (Aug 22, 2001)

deniseO30 said:


> You should be able to nick the brass with small metal cutting blade from a jig saw. then carefully pry the brass inward. (almost the same as replacing a cutless bearing but much smaller of course. Plumbers and pipe fitters do this often with broken pipes. Warning, the thread may be metric! Get a new drain from yanmar. You could maybe even find a large self tapping bolt with rubber and metal washers to seal it. there used to be something like that available at plumbing supply houses.


Thanks, I already got the replacement parts from Yanmar, of course they are not the same as they realized their error and retrofitted with a stronger part!

I may just seal it up for the summer and deal with it over the winter.


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## VallelyJ (Nov 21, 2008)

Just leave the broken threaded end in place and tap the hole in it for a smaller plug. That original bronze threaded end isn't going anyplace. And if you clip the female threads in the engine block while trying to cut it out, whatever you put in there will always leak.
When you need to drain the antifreeze, you can just pull the smaller plug back out. But use a brass capscrew or plug, and not a steel one, or that one will bond in place too. And use some anti-sieze compond on the threads.
All due respect to JBWeld and it's adherants (pun) but I wouldn't trust it to keep the antifreeze in your engine.


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## casey1999 (Oct 18, 2010)

VallelyJ said:


> Just leave the broken threaded end in place and tap the hole in it for a smaller plug. That original bronze threaded end isn't going anyplace. And if you clip the female threads in the engine block while trying to cut it out, whatever you put in there will always leak.
> When you need to drain the antifreeze, you can just pull the smaller plug back out. But use a brass capscrew or plug, and not a steel one, or that one will bond in place too. And use some anti-sieze compond on the threads.
> All due respect to JBWeld and it's adherants (pun) but I wouldn't trust it to keep the antifreeze in your engine.


I'm with you. The last thing you want to do is make it a bigger problem than what you have- somthing that may require you to pull the engine to fix a $10 dollar part, and somthing not really necessary. Been there when I was trying to remove the zinc anode plugs on my Yanmar 3gmd.
Good Luck


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## hellosailor (Apr 11, 2006)

Try shooting the remainder of the plug with PBlaster. Not WD40, but PBlaster. It chemically attacks the corrosion, and at that point you may be able to wedge in a tool and unscrew the stub.

If that doesn't work there's a freeze spray from loctite that unsticks things by freezing them and contracting the metals apart.

I'd suggest patience and trying to outsmart it, rather than brute force. Yes, careful drilling (often by hand not power) or reaming may allow you to chew it out, but try the PBlaster or the freeze spray first. I've seen them unstick all sorts of evil bits.


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## casey1999 (Oct 18, 2010)

hellosailor said:


> Try shooting the remainder of the plug with PBlaster. Not WD40, but PBlaster. It chemically attacks the corrosion, and at that point you may be able to wedge in a tool and unscrew the stub.
> 
> If that doesn't work there's a freeze spray from loctite that unsticks things by freezing them and contracting the metals apart.
> 
> I'd suggest patience and trying to outsmart it, rather than brute force. Yes, careful drilling (often by hand not power) or reaming may allow you to chew it out, but try the PBlaster or the freeze spray first. I've seen them unstick all sorts of evil bits.


I tried the freeze spray on my corroded zinc plugs. Found the spray basically useless. I also bought some dry ice to try to contract the siezed plug, but had no luck. I did use PB blaster, but what I found is the threads were so siezed that I do not think the PB blaster could penetrate enough to help. I finally used a plumbers propane torch to heat to about 180 deg F and the used a socket with a 4 foot breaker bar (pipe)- I was fearful I was going to strip the threads but the plug came out. Would not suggest this method for the drain plug problem the poster has. I would leave it until a point in time where you need to pull the engine for say a rebuild and deal with it then.


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## miatapaul (Dec 15, 2006)

casey1999 said:


> I tried the freeze spray on my corroded zinc plugs. Found the spray basically useless. I also bought some dry ice to try to contract the siezed plug, but had no luck. I did use PB blaster, but what I found is the threads were so siezed that I do not think the PB blaster could penetrate enough to help. I finally used a plumbers propane torch to heat to about 180 deg F and the used a socket with a 4 foot breaker bar (pipe)- I was fearful I was going to strip the threads but the plug came out. Would not suggest this method for the drain plug problem the poster has. I would leave it until a point in time where you need to pull the engine for say a rebuild and deal with it then.


Yea, the Locktite freeze spray seems to be useless. My favorite weapon against rust is Wurth Rost off + it is expensive but worth every penny. I used to drive a lot of old rusty British cars and this stuff works better than than anything else I have tried. One can will last a long time and is worth keeping on the boat. If any chemical will work it is this stuff.


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## RobGallagher (Aug 22, 2001)

In Conclusion:

I tried the Ez out's with the PB Blaster, Kroil and even the "freeze spray".

FWIW, the freeze spray or Kroil or both did do "something" as the ez out went in even further...lol.

I backed out the original ez out and put in the next size up, more Koil and freeze spray. Would not budge.

I ended up (with the help of a friend, fellow sailnetter, and owner of my previous boat) tapping the existing hole and putting in a stainless bolt.

I motored for a couple of hours to test her out. Does not seem to be leaking so all's well that ends well.


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## arf145 (Jul 25, 2007)

Regarding the tight access on that side of the Yanmar: we have the same problem, but I alleviated it a bit by putting a large screw-in deck plate (8 or 10") in the adjoining wall. In our case this gives some access from the head. Couldn't have replaced the fuel lift pump without it.


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## VallelyJ (Nov 21, 2008)

Now that you know your fix worked, I suggest you get that stainless steel bolt out while you still can and put a brass one in, or you'll end up snapping the head off it once the SS bonds to the brass it's in--exactly as the original brass fitting did to the cast iron. And you won't be able to drill and tap the center of it as easily.
I like the deckplate idea, too. They can be perfect for getting occasional access to tight places--vented loops, etc.
John V.


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## rugosa (Aug 30, 2011)

RobGallagher said:


> I should have mentioned, there is very little room to work on the side of the engine.


Of course, it's a boat, and too few are designed/built for after build service convenience - IMHO


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## RobGallagher (Aug 22, 2001)

VallelyJ said:


> Now that you know your fix worked, I suggest you get that stainless steel bolt out while you still can and put a brass one in, or you'll end up snapping the head off it once the SS bonds to the brass it's in--exactly as the original brass fitting did to the cast iron. And you won't be able to drill and tap the center of it as easily.
> I like the deckplate idea, too. They can be perfect for getting occasional access to tight places--vented loops, etc.
> John V.


I was pondering that. Anyway to tell if the original fitting is brass or bronze? Or does it matter if I mix brass and bronze?

Thanks for the advise.


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## hellosailor (Apr 11, 2006)

Brass and bronze are sisters. In theory Yanmar can tell you what they used, and in theory they built a marine engine so it would be bronze. But I wouldn't bet on it. Might be simpler and reasonably safe to just use a bronze bolt and put tefgel or antiseize on the threads before you bolt it in.

A metric(?) bolt in yellow metal? Gonna be mail order for most of us. Does the other one need replacing while you are at it?


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## RobGallagher (Aug 22, 2001)

hellosailor said:


> Brass and bronze are sisters. In theory Yanmar can tell you what they used, and in theory they built a marine engine so it would be bronze. But I wouldn't bet on it. Might be simpler and reasonably safe to just use a bronze bolt and put tefgel or antiseize on the threads before you bolt it in.
> 
> A metric(?) bolt in yellow metal? Gonna be mail order for most of us. Does the other one need replacing while you are at it?


The other one is not leaking. I have the replacement and planned on replacing both as they have a plastic bolt, yes plastic.

I must admit that I'm afraid to tackle the other one. I don't want to risk breaking it off. I am going to check to see if the bronze bolt from the replacement unit fits in the old fitting.

There are a couple of good old hardware stores in my area that still stock hard to find items so maybe I'll get lucky.

The stainless bolt is wrapped in teflon tape so I think I have a bit of time before it starts to seize.

Thanks again to all replies, this has been interesting...


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## VallelyJ (Nov 21, 2008)

I would think you'd be OK with the teflon tape. Brass and bronze are much closer in nobility than either is to stainless, and that's the key to avoiding corrosion.
Give it a little twist with a wrench now and then and see if it still moves readily.
I would think you could tell whether it's brass or bronze by looking at the part that broke off. Somehow I doubt they used bronze in that part--a lot of engines have brass fittings for coolant and the fact that it's in a boat engine shouldn't matter too much.
If it's possible to cut an access hole & deck plate by any engine part like that, as another person suggested, the easier access can make it less likely that you'll break something or strip threads working on it. I use them a lot on my boat and they're easy to put in.


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## dinosdad (Nov 19, 2010)

The fitting in the block is brass.. If you can't find a brass bolt let me know,
And when I get a chance I'll cut one on a lathe for you,
With a nice beefy hex head , we won't even steal your sandals this time!
We got time the stainless bolt won't glue itself to the brass all that quick,
Not with a closed coolant system.....


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