I am having the hardest time getting the elbow off.. See Pic.. Do I remove the elbow or the flange that's connected to the engine? Even tried hitting it with a hammer. Any ideas? Thanks! -Jon
Getting that Darn Mixing Elbow Off
- Thread starter PGIJon
- Start date
That union in the center is LH threads on one side and RH on the other and I can't remember which is which but make sure you are turning the right way.
I always remove all three pieces from the engine, not that I can get them apart on the bench either, and usually end up replacing all 3.
I always remove all three pieces from the engine, not that I can get them apart on the bench either, and usually end up replacing all 3.
It is highly unlikely you will succeed getting this assembly apart unless you remove it. So unbolt the whole works at the cylinder head.
There are four nuts (some have three) which fasten this assembly to the cylinder head. These fasteners are on the very far left in your photo. Carefully undo these nuts/bolts and see to it you do not break the studs (or bolts) which thread into the head.
Take the entire assembly to your shop. Disassembly requires considerable heat (I use a careful application with an oxy-acetylene torch which permits temperatures to be made very high), well fitted wrenches, and a large vise. An automotive machine shop or marine mechanical shop can disassemble for you if you do not have the tools. Be mindful that the threaded connector is right hand threads at at the U shaped (silver) mixing unit and left hand threads at the (rusty) exhaust elbow.
Reassemble with new parts as necessary including a new gasket, new nuts and/or bolts. Use plenty of anti-seize lubricant. I use Permatex Anti Seize and have no problems undoing the fasteners even many months later. The head to exhaust unit fasteners do not need to be way tight - I reckon about 20 ft lbs probably less but check your manual to verify how tight.
Charles
There are four nuts (some have three) which fasten this assembly to the cylinder head. These fasteners are on the very far left in your photo. Carefully undo these nuts/bolts and see to it you do not break the studs (or bolts) which thread into the head.
Take the entire assembly to your shop. Disassembly requires considerable heat (I use a careful application with an oxy-acetylene torch which permits temperatures to be made very high), well fitted wrenches, and a large vise. An automotive machine shop or marine mechanical shop can disassemble for you if you do not have the tools. Be mindful that the threaded connector is right hand threads at at the U shaped (silver) mixing unit and left hand threads at the (rusty) exhaust elbow.
Reassemble with new parts as necessary including a new gasket, new nuts and/or bolts. Use plenty of anti-seize lubricant. I use Permatex Anti Seize and have no problems undoing the fasteners even many months later. The head to exhaust unit fasteners do not need to be way tight - I reckon about 20 ft lbs probably less but check your manual to verify how tight.
Charles
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I agree with Charles. This sort only comes off with prayer.
In a preventative note the Never Seize product is recommended during assembly.
In a preventative note the Never Seize product is recommended during assembly.
Hidden Way Back There ......................
........................ you'll find four bolts located as shown on the attachment to the exhaust manifold.
Follow all previous instrucions posts.
The one additional thing I've done is make a jig for setting the screwed dimensions before I install the assembly again as trying to do it in place is a real bear. My exhaust assembly sits in a shoe box and I have to be exact +/- 1/4" so it fits between the casing and the overflow tank.
........................ you'll find four bolts located as shown on the attachment to the exhaust manifold.
Follow all previous instrucions posts.
The one additional thing I've done is make a jig for setting the screwed dimensions before I install the assembly again as trying to do it in place is a real bear. My exhaust assembly sits in a shoe box and I have to be exact +/- 1/4" so it fits between the casing and the overflow tank.
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Ditto
Well be careful getting the whole thing removed with the 4 or how many bolts on to the back of head maybe a little heat may help.
I took the whole thing to outboard shop on 776 before bridge and they took it
apart $20 for me,I don't have big tools any more.
I gave mine a good cleaning out on my 2007 3YM30 and been running great,
I have found taking it off every few years and cleaning really works great.
Nick
Well be careful getting the whole thing removed with the 4 or how many bolts on to the back of head maybe a little heat may help.
I took the whole thing to outboard shop on 776 before bridge and they took it
apart $20 for me,I don't have big tools any more.
I gave mine a good cleaning out on my 2007 3YM30 and been running great,
I have found taking it off every few years and cleaning really works great.
Nick
Agree with previous statements about removing the whole thing from engine. On mine it is also easier to bring the exhaust hose with it after disconnecting at the waterlift.
Mine has the 4-bolts attachment. Don't remember which are which but there are 2 short ones and 2 long ones. Seem to remember they are 12mm. See pix. If like Seadaddler you can get someone to separate the elbow from the nipple with the left hand thread, do so it will save you a lot of aggravation. Good luck
Mine has the 4-bolts attachment. Don't remember which are which but there are 2 short ones and 2 long ones. Seem to remember they are 12mm. See pix. If like Seadaddler you can get someone to separate the elbow from the nipple with the left hand thread, do so it will save you a lot of aggravation. Good luck
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Thank you all... Once again this forum has been invaluable!
I'm going to take it all off as a single unit and then, depending how bad it looks inside will take it to the place Nick mentioned and have them separate it for me.
I've already ordered a bottle of Never Seize. Do I just paint it on? Do I also use any pipe dope... Hmmmm, that may not have come out exactly right.. I mean the stuff you put on the pipe threads. Anyway.. How exactly do I use the Never Seize. Claude, is that Teflon Tape that I see on yours?
Thanks Jon
I'm going to take it all off as a single unit and then, depending how bad it looks inside will take it to the place Nick mentioned and have them separate it for me.
I've already ordered a bottle of Never Seize. Do I just paint it on? Do I also use any pipe dope... Hmmmm, that may not have come out exactly right.. I mean the stuff you put on the pipe threads. Anyway.. How exactly do I use the Never Seize. Claude, is that Teflon Tape that I see on yours?
Thanks Jon
Sorry Jon I was not clear. Mine is the same u-shape elbow and I wanted to show the 4-bolt piece that attaches to the manifold. The picture posted is not from my engine. That elbow is probably a slightly different model as it has a large bronze elbow screwed in it which is probably to bring in the cooling water after going through an anti-siphon valve. I found a pix of my elbow (attached) and you can see the cooling water is brought in through the small bronze 90 deg. elbow screwed in near the top. No teflon on mine. Cooling water hose also going through anti-siphon located on back bulk-head. Sorry if I misled you.
On the pix here you can see the shorter bolts are the upper ones. When re-installing with a new gasket, it is sometimes easier to take one of the longer one and insert it in the upper position to hold the fairly heavy unit in place. Then you can insert the other long one on the bottom opposite side and tighten a little bit. This will allow you to install one short bolt in the free hole on the upper corner, then remove the long one you had first used and install in its bottom position. Once all 4 are in place, tighten evenly. I find it easier to install the short piece of exhaust hose after the elbow is secured in place. Good luck.
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Which way does the water inlet elbow go?
Mine has always come in from the top, but I see horizontal and the water elbow turned down in the pictures here.
I believe MaineSail recommended some type of furnance high temp pipe dope on the threads of the adaptor between the flange and the exhaust elbow. They have it at home depot.
Not to increase your workload but if never done while you got the elbow off you can remove your exhaust manifold to be certain there isn't a build up of carbon. I did mine this year but wasn't bad since it was done years ago and I don't idle for long and make an effort to run at higher rpms.
Mine has always come in from the top, but I see horizontal and the water elbow turned down in the pictures here.
I believe MaineSail recommended some type of furnance high temp pipe dope on the threads of the adaptor between the flange and the exhaust elbow. They have it at home depot.
Not to increase your workload but if never done while you got the elbow off you can remove your exhaust manifold to be certain there isn't a build up of carbon. I did mine this year but wasn't bad since it was done years ago and I don't idle for long and make an effort to run at higher rpms.
Let me assure you, as have others, that you will never disassemble the elbow on the engine. When my engine overheated as I was leaving Marina del Rey I decided the elbow might be the cuprit. Being naive, I wasted a couple of hours and a spinal disc or two before I took the whole assembly off. I then spent [read: waste] 3 hours with a 14" pipe wrench. When reality finally set in it was Sunday and I was just about to give up searching for a shop, when I espied a small greasy shop populated by numerous hulk in various states of erosion off an alley with an equally greasy fellow working on something at a leisurely pace. He took one look at the elbow and hauled me off to a vise that probably once held the Titanic, and handed me the mother of all pipe wrenches. All that work only confirmed what everyone had already said: You'll need a new one.
I should have noted also when my elbow was changed two years ago tje coupler was cut off the flange and carefully removed from the flange so the flange could be reused.
Blitz, mine is also horizontal. Picture was taken on workbench before installing on engine and giving it its final position when installing.