Hose rubbing on propeller shaft

[dmksails]

I had the yard replace the hoses on my engine (Yanmar 3GM30F). One of the hoses has a shield on it that is in contact with the shaft.

The top of the hose connects to a U-shaped fixture that connects to the engine. I think that if this was turn counter-clockwise a bit that the hose would be pulled away from the shaft.

I'm not sure what this U-shaped item is called, and I'm not sure about just how hard it would be to get it turned. Any advice?

[Flyingriki]

Sure would have the yard correct poor workmanship.

[model 10]

I guess you can't tell the yard to fix it? Usually when they screw up that bad they will fix it right away.

[dmksails]

I will be trying to get the yard to redo - and in the past they have been pretty good about that. Looking to get info in case I need to attempt the repair either now or in the future. For me to try I will first need to get the proper tools - like a big enough pipe wrench

[model 10]

You bought an old boat? You need all kinds of tools.
There is probably not enough room for the shield but they installed it anyway, a poor design. Take a wedge of some sort (screw driver) and drive it in between the shaft and the shield and whack it good.

[jimbunyard]

Originally Posted by dmksails

I had the yard replace the hoses on my engine (Yanmar 3GM30F). One of the hoses has a shield on it that is in contact with the shaft.

The top of the hose connects to a U-shaped fixture that connects to the engine. I think that if this was turn counter-clockwise a bit that the hose would be pulled away from the shaft.

I'm not sure what this U-shaped item is called, and I'm not sure about just how hard it would be to get it turned. Any advice?

The big silver U is an exhaust mixing elbow. If memory serves there is a nipple that connects it to the ex manifold that is threaded with left hand thread on one end and right hand on the other, with the center hexagonally shaped for a big ass wrench. If you're lucky you might be able to turn the whole assembly slightly with a big pipe wrench, and still avoid causing an exhaust leak...

If you're unlucky the thing will be frozen solid and you'll break something trying to get it to turn...

If the yard won't fix it, you might be able to rig something up to pull the hose to the side, just don't use so much tension you pull it off the el or the muffler.

Conversely, you might be able to get another piece of exhaust hose about an inch longer and use the extra length to make the hose pooch out to the side, which is probably what the yard should have done to begin with.

That's really an awkward setup to deal with, don't envy anyone having to install either of those hoses. A reputable yard should back their work though, and I hope you can get yours to make it good.

[Wotname]

Originally Posted by jimbunyard

The big silver U is an exhaust mixing elbow. If memory serves there is a nipple that connects it to the ex manifold that is threaded with left hand thread on one end and right hand on the other, with the center hexagonally shaped for a big ass wrench. If you're lucky you might be able to turn the whole assembly slightly with a big pipe wrench, and still avoid causing an exhaust leak...

If you're unlucky the thing will be frozen solid and you'll break something trying to get it to turn.........

FWIW, it looks to me like the water injection point is on the wrong side of the U bend.
If so, this needs to be sorted first and then somehow route the first part of the flexible exhaust hose away from the shaft. But it looks very difficult from where the water trap is located (under the shaft)?

Or have I missed something...

[chris95040]

So is that the waterlift muffler under the shaft? No sensible installation would have a hose so close to a shaft. Begging for trouble.

Really all those hoses are a mess, imagine if steam starts spurting from somewhere in there while you are in a tight spot. I'd hate to debug that rats nest. I'd read up on marine engine installs and neaten all that up.

On edit, it may look worse in the photo than it actually is... Grass may always be greener on the other guy's lawn but the other guy's engine room is always the bigger rat's nest...

[jimbunyard]

Yeah, it looks a mess to work on...

After looking at it again, I'm not so sure what I'm seeing.

There appear to be at least two shields, two around the red striped hoses, which, though they're (or at least one) is marked 'fuel', the one that seems might be causing the problem (by running between the trident exhaust hose on the muffler inlet and the hull of the boat) looks like it is attached to the raw water intake and the inlet side of the water strainer. There may also be a shield around the lower part of the exhaust hose where it attaches to the muffler. See the OP's original picture below.

In the second picture (I've doctored the original a bit) there is an alternative routing for the raw water inlet hose shown that may allow enough room to let the exhaust hose be pulled or pushed out of the way, if it is in fact the hose that is rubbing against the shaft...

The exhaust elbow is correct, that's just the way it's designed, it can only be hooked up one way...

Of course this should all be taken with a rather large grain of salt until we get confirmation from the OP as to what we're actually supposed to be seeing...

[chris95040]

Originally Posted by Wotname

FWIW, it looks to me like the water injection point is on the wrong side of the U bend.
If so, this needs to be sorted first and then somehow route the first part of the flexible exhaust hose away from the shaft. But it looks very difficult from where the water trap is located (under the shaft)?

Or have I missed something...

No it's probably correct. Lots of elbows have the h2o injection on that side, then there's a water jacket that brings it over to the output side. Routing the water this way keeps the tippy top of the elbow cool instead of stupid hot.

[Wotname]

Originally Posted by chris95040

No it's probably correct. Lots of elbows have the h2o injection on that side, then there's a water jacket that brings it over to the output side. Routing the water this way keeps the tippy top of the elbow cool instead of stupid hot.

Thanks, I got it wrong at the first look

[boeing1]

Not good, the yard should correct, however if they will not you should

[Seighlor]

Don't mess with it. Make the yard aware of the problem. If they're at all reputable, they will take care of it.

[dmksails]

I was back at the boat today with the intention of seeing if I could move the elbow. Found that the lock nut was never tightened down and that there may not be enough hose to turn it. You can see that the top clamp is not fully on the hose.

Definitely going back to the yard on this.

[jimbunyard]

If in fact the red striped hose that connects to the inlet on the water strainer is the same hose that connects to the valve on the starboard side, and it is wedged between the muffler inlet hose and the side of the boat, get the yard to move it so it follows the routing in the doctored picture above.

The muffler inlet exhaust hose is too short, it appears by about 1 1/2 - 2". Don't let them get away with reusing the one they've cut incorrectly, if they balk, offer to buy the correct length of hose, and either suck it up or fight with them about it after the job is completed correctly...