bolts snapped off. what now?

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Jun 3, 2004
298
'79 Hunter 33' HUN33190M79L Olympia
Trying to unbolt the mixing elbow mount from the exhaust manifold on my 2qm15, one bolt came out, three snapped off. Now what do I have to do????? This is probably an easy question for most mechanics but I'm not one! Any fast reply greatly appreciated!
 

kenn

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Apr 18, 2009
1,271
CL Sandpiper 565 Toronto
Assuming you've now got the mixing elbow off...is there some bolt shaft still sticking out?

If yes, then you might be able to clamp some Vice-Grips® onto the bolt shaft and twist them out. Several commentators have mentioned that PB Blaster will help to loosen rusty bolts, so try some of that onto the bolt and let it work a bit.

If the bolt snapped flush with the manifold, then you probably have to drill the bolts out... and that's something I'm not too good at.
 
Aug 2, 2005
1,155
Pearson 33-2 & Typhoon 18 Seneca Lake
Hello Steve, Definitely use the spray to help the freeing of the bolts. Don't rush it.......letting the chemical work for a couple of days is good and perhaps apply some heat to the area with a heat gun. If the bolts do protrude a bit lightly tapping on them can aid the penetration of the chemicals.
If you need to drill the bolts out I wish you well. I have never had much success with drilling and then using an appropriate size of Easy-Out. I nearly always managed to snap off the easy out! Check with others you know who may have had better success.
Best Wishes, Phil
 
Jun 3, 2004
298
'79 Hunter 33' HUN33190M79L Olympia
The elbow is still stuck to the mount so if I can get that off, the bolts should be protruding. It seems pretty firmly still stuck on though, I tapped it medium hard with a hammer with no give. Its stuck on well enough that I put the one bolt back in and was able to run the motor. So what now?
 
Feb 26, 2004
23,362
Catalina 34 224 Maple Bay, BC, Canada
Use the PB Blaster on the connection from the elbow to the engine. As mentioned, give it time to work, mine took over a week or daily spraying. It ain't easy. Give it time to work. Oh, I said that already.

Only other thing is to get a trusted, I say trusted, mechanic who knows this stuff unless you have a machine shop skipper on your dock who is friendly.

Good luck. As far as zen is concerned, sometimes you just have to get into a "mode" that says your engine won't be working for some time until you get it fixed. It's a state of mind I apply when I do major engine work. While the PB Blaster is working, I find other things to fix.:doh:
 

KD3PC

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Sep 25, 2008
1,069
boatless rainbow Callao, VA
you will need a "no-bounce" hammer and some good solvent. PB is good but don't let it get on anything but the target bolts.

Tap the housing around and around, again heat as you do this may help. Once you get the elbow off. Then soak the studs for a few days. Then try the vise grips and some more solvent, but don't get in a hurry or the remaining studs may break off.

Next step, if this approach fails, is to drill and use easy outs, or center drill small and move up in size until you get to within the threads and tap out the remaining metal and then run a correct sized tap in the holes.

Best of luck.
 
Jan 3, 2009
821
Marine Trader 34 Where Ever I am
Stephen, The advise you have received about the PB Blaster is good and so is being patient. It has taken me a week sometimes to free things up. One trick I like to use is to saturate a piece of cloth with the PB and tightly wrap it around the stud. I reapply each day to the stud and the rag. It seems to speed up the process. I also use a combination PB Blaster and Corrosion Block. At some point one day it just turns as if it had never been a problem. Chuck
 

BobM

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Jun 10, 2004
3,269
S2 9.2A Winthrop, MA
There was a good article in Good Old Boat about this situation...I'll see if I can dig it out. I will also pray to the 2QM15 God for you...I have just such an idol in my boat too!
 
Dec 25, 2008
1,580
catalina 310 Elk River
If you use an easyout, don't break it off, because then you really have a problem. It is hardened steel and very difficult to drill out. Better just drill it out and re-tap.
 
Jan 14, 2011
243
tanzer tanzer 28 bathurst nb
ok all! first and easiest way is get a hold of some portable oxy acetylene torch heat up the steel AROUND the bolt untli redish, this will make the metal expand and will free the bolt, and easy out will melt before the steel due to its carbon content, good luck and watch for fire, oh and use a small welding tip on the torch.
 
Jan 22, 1999
62
Hunter 35 PENSACOLA, FL
Steve,
Don't waste your time.
Buy a new one.
You'll have problems with this elbow the rest of your ownership.

Broad Reach
 
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Ross

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Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
If you have to drill you can buy left hand drill bits from McMaster-Carr. Quite often the stud will back its self out when drilling with a left hand bit.
If you get anywhere close to the melting point of any metal on that engine it is much too hot and the melting temperature of high carbon steel is pretty close to the melting point of cast iron and way above the melting point of aluminum and bronze.
 

Johnb

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Jan 22, 2008
1,505
Hunter 37-cutter Richmond CA
When I replaced my mixing elbow on the 3QM30 I also removed the exhaust manifold because the end needed refacing. The nuts on the studs that hold the exhaust mainfold on came off easily. There is a fuel filter that is mounted to the exhaust manifold that had to be unbolted and moved to one side.

Anyway the point is, it may be quite easy to undo the exhaust manifold and remove it and then take the whole shebang to a machine shop to be dealt with. That may well be worth doing anyway. Once I had mine off there was also a lot of corrosion underneath where what used to be a drain was rusting out.
 
Jul 18, 2009
274
marine clipper 21 ft santa ana Southern Lakes,Yukon
permatex makes a product called freeze and free..a can is about eleven bucks,after penetrating oil soaking you can warm the steel around the stud and then give the stud end a blast of the freeze and free (it will bring the stud temp down to minus 45 degrees)..
 

zeehag

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Mar 26, 2009
3,198
1976 formosa 41 yankee clipper santa barbara. ca.(not there)
i recently had the 2 bolts holding my alternator bracket snap off inside block--i found a friend with a steady hand and he easy -outed them and installed new and re aligned the bracket so i dont have the problem i had anymore--make sure the mechanic has steady hands......
 

Johnb

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Jan 22, 2008
1,505
Hunter 37-cutter Richmond CA
I just remembered - I did a previous post on this topic

While removing the mixing elbow to exhaust manifold flange a bolt broke off in the exhaust manifold, so I took the exhaust manifold off as well. I was lucky in that regard because all six of the nuts came loose (one stud came out with the nut) – it turns out they are stainless.

I could not get the exhaust hose loose from the mixing elbow so I hack sawed along the length of it and then pried it off.

Once I got the exhaust manifold out I found that exhaust gas had been blowing via the exhaust end gasket into the water passage and the drain valve was plugged with soot. Because of that leak the surfaces were pitted by corrosion.

We then did the following
Purchase new mixing elbow $150
Purchase new head to manifold and manifold to mixing elbow gaskets $30
At a local machine shop, clean up the mating surfaces at the exhaust manifold to mixing elbow flange (grind down where corroded); drill out broken bolt and put in a helicoil; grind down and weld a plate over a corroded freeze plug on the underneath of the exhaust manifold; unscrew the old mixing elbow from the mixing elbow flange and screw the new one in (needed a BIGGER pipe wrench than I own) $125
Purchase new 31” of exhaust hose and clamps $42

The composite picture shows the old elbow, newly machined surfaces and welded over freeze plug on the manifold. The threaded drain plug hole is to the right of the freeze plug.
 

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Jun 4, 2011
32
Oday 192 Bald Eagle State Park, PA
I'll reiterate what others have said. First PB Blaster, there is no substitute. Second, if there is bolt exposed vicked tight vise grips. If there is not bolt shaft exposed, left handed drill bits are a life saver. In my experience, 80% of the time the bolt comes out when drilled with a backwards bit.
 

NYSail

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Jan 6, 2006
3,184
Beneteau 423 Mt. Sinai, NY
Make sure the PB Blaster DOES NOT get on any other engine parts especially gasket seams as it will ruin them. Stuff works great but be careful.

Good Luck!
 
Feb 14, 2009
4
Challenger 35 cape town
Only thing I can add to this excellent post is , if using the vice grips , clamp as hard as possible and then apply anti clockwise pressure followed by a clockwise pressure - or in plain language , wiggle it.
As soon as you feel play , keep up the action gently - the wiggle helps the PB to penetrate.
BEWARE the easing out action isnt the shearing off flush with the block ! Easy does it !

Kris
 
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