follow up on exhast elbow

cid

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Hi once again,futher to my earlier posts on the yanmar exhaust elbow,I attach aphoto to show the different parts.I trust you now can see the new piece which a friend welded up for me.The wholelot bolts on nicely to the engine and appears to be working ok.Thanks for all the prvious comments and suggestions.

exhaustelbow2.jpg
 
Looks a good solution although I dont know how the original inner pipe was fixed. Is the new one as thick as the original. It'll be subject to a fair bit of corrosion where the water is injected I suspect.
Did you think to get a spare one made at the same time?
 
[ QUOTE ]
Are you sure the Dia is sufficient, it looks a lot smaller & no injection spigot /forums/images/graemlins/confused.gif

[/ QUOTE ] Do keep up at the back. His earlier posts explained the cunning plan. The new smaller dia pipe sits inside the old elbow which has had the inner pipe removed, the water injection spigot is still there.
 
Hi Cid,
Sorry I haven't send you the details on the gasket cement yet, I haven't been at the boat yet. Do you still need it?

Looking at your pictures I have a hard time believing the diameter of the exhaust pipe of the old and the new are the same. Or do the two parts belong together? Is the left one sticking in the right one?

Cheers,

Arno
 
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Ah its an inner pipe

[/ QUOTE ] You should have looked up the original thread , like wot I done!

It would have been better though if cid had continued with the original himself instead of starting a new one

Gasket cement on those joints?

If the flanges are flat and in good nick I dont think I'd use any at all. If necessary an exhaust system cement from Halfords should do. (Firegum or GunGum)
 
OK.Thanks for replies.Yes one goes into the other.In practice I used two of the gaskets on the left which I made up.I gum gumed one to the block the other to the first part.Then the next gasket is stuck to the last part with a water/heat resistant silocone(cant think of name at present).Then the whole lot was bolted to the engine.
 
I'm not sure about this idea. In the original design the water meets exhaust at a high temperature, which then expands and mixes along the metal elbow, cooling as it goes. With the new design the hot gas makes its way almost to the rubber hose before any water is mixed. Furthermore, you have not presumably carried out any tests and don't know how well the gasses will mix with the water. I am very dubious.
 
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I'm not sure about this idea. In the original design ........

[/ QUOTE ] Do you not understand? This is not a 'new design' it's simply a slightly different solution to the engineering of the original design, the water is injected in exactly the same way.
 
[ QUOTE ]
Do you not understand? This is not a 'new design' it's simply a slightly different solution to the engineering of the original design, the water is injected in exactly the same way.

[/ QUOTE ]Have a look at where the water is being injected in the original and where it will meet the gasses in the new design.
 
Oh, BTW, there will also be a greater back pressure in the new design....don't know if that is an issue as this isn't my field. Might be a potential problem at full power?
 
Looks good to me....

[ QUOTE ]
It would have been better though if cid had continued with the original himself instead of starting a new one


[/ QUOTE ]

Sorry to disagree, Vic, but the original thread is *many* pages back - well worth starting anothe thread in this case (IMHO).

Thanks Cid,

Andy
 
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Are you sure the Dia is sufficient, it looks a lot smaller & no injection spigot /forums/images/graemlins/confused.gif

[/ QUOTE ]

This is how the original looks and gives an idea of the make up

exhaust01.jpg


exhaust02.jpg


exhaust03.jpg
 
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Sorry to disagree, Vic, but the original thread is *many* pages back

[/ QUOTE ] Doesn't matter how many pages back it is. Adding a new post to it will bring it to the top of the pile again ........ unless you are not viewing in last post order. Surely no one views in creation date order do they ?
 
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