The mixing elbow on my '98 H376 broke off from the manifold. My mechanic, whom I trust implicitly, attributes this to a design flaw. He says that the unsupported weight of the elbow coupled with the heat and vibration of the engine puts too much stress on the connection to the manifold. His solution is to have his welder fashion a new fitting. I'm not sure of the details as this is based on a preliminary phone conversation and I'm no mechanic. He did say that he could replace it as was done previously but that it would probably fail again in a few years. We were very fortunate that when this mishap occurred, we were returning from a longer weekend cruise and were only a few hundred yards from our marina entrance on a beautiful calm day. My fear is this reoccurring in the middle of the Chesapeake Bay in heavy weather. Has anyone else experienced this issue and, if so, what was your solution.
H376 Mixing Elbow
- Thread starter rkssail
- Start date
It’s a rusted 26 year old elbow. Had the rust and the cause for it been dealt with in a timely manner, it’s likely the original cast would have lasted another 20 years. It doesn’t require support, just proper maintenance.
And that pretty well sums it up. The connector has corroded through.
I've inspected mine (on occasion) and replaced it twice in 24 years when it probably didn't need it.
As shown on my mixing elbow after an internal inspection, all the parts are heavy cast iron with the exception of that screwed connector between the two heavy parts. Yours is slightly different. The connectors we have are just thin pipe, the weakest part of the assembly. The connector is plain steel and corrodes more easily than the other two cast iron parts. You've got to keep an eye on its INTERNAL condition.
Have it replaced and make a note to have it inspected in 4 - 5 years. Make sure none of those hoses connected to your model are pulling on the assembly.
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I had a similar experience. The threaded coupler broke as we were prepping to leave the dock. I noticed a change in tone of the exhaust and went below, smelt the exhaust and saw the water spewing out the manifold so shut the engine down.
I was able to easily remove the coupler from the manifold, so I ordered a new stainless elbow and coupler for significantly less than OEM Yanmar parts. It took less time to remove the broken parts and install the new parts than it did to clean up the mess made when the coupler broke, maybe 10 minutes total for the removal and replacement.
BTW my original coupler lasted 32 years.
I was able to easily remove the coupler from the manifold, so I ordered a new stainless elbow and coupler for significantly less than OEM Yanmar parts. It took less time to remove the broken parts and install the new parts than it did to clean up the mess made when the coupler broke, maybe 10 minutes total for the removal and replacement.
BTW my original coupler lasted 32 years.