I have a 1979 Hunter 30 with a Yanmar 2GM20. The yard mechanic tells me that the strut is bent and needs to be cut off and straightened. Another mechanic tells me that it looks like it is offset to allow the shaft to be removed since the rudder and skeg would impede the removal if the strut and shaft were straight. I have asked the first mechanic to look at the engine installation to verify that the engine was not installed offset to allow the shaft to be removed without taking off the strut. We pulled the prop and the cutless bearing is slightly worn but not overly ovaled as I would expect if the strut was sreiously bent. I have not noticed any unusual vibration when running the engine prior to hauling the boat. Question: Is the strut and shaft offset on a 79 Hunter 30? Thanks, Tim the Tulman
Shaft Offset
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Whoa
1. What would possess the first mechanic to say that? 2. If it runs fine with no vibration, don't do it.
1. What would possess the first mechanic to say that? 2. If it runs fine with no vibration, don't do it.
Bent
I had a 1980 H30 and I can tell you that the shaft is not offset. Your strut is bent! Furthermore, when you replace or repair the stut, make sure that the shaft is centered in the shaft log thru hull. Some factory installations allowed the shaft to rub against the shaft log which eventually caused them to fail and leak. You have to center the shaft by adjusting the placement of the strut, then align the engine to the new shaft position. There have been some discussion on this forum about replacing the stut so check the archives.
I had a 1980 H30 and I can tell you that the shaft is not offset. Your strut is bent! Furthermore, when you replace or repair the stut, make sure that the shaft is centered in the shaft log thru hull. Some factory installations allowed the shaft to rub against the shaft log which eventually caused them to fail and leak. You have to center the shaft by adjusting the placement of the strut, then align the engine to the new shaft position. There have been some discussion on this forum about replacing the stut so check the archives.
Bent versus offset shaft
The scary thing about this question is that my dad, the designer, was a big proponent of offset prop shafts, ala Herreshoff. The Cherubini 44 is a notable example. It is entirely possible that some of these boats got to have that benefit too. I honestly do not know which ones might have had this. The easiest way to check is to see if the engine logs are angled. Even a little angle will be noticeable. Sorry to be less than techie on this one. I really don't know. I just know that an angled shaft is not only NOT a far-out idea, it's actually better. Investigate his before I go down to the boatyard and let me know! JC 2
The scary thing about this question is that my dad, the designer, was a big proponent of offset prop shafts, ala Herreshoff. The Cherubini 44 is a notable example. It is entirely possible that some of these boats got to have that benefit too. I honestly do not know which ones might have had this. The easiest way to check is to see if the engine logs are angled. Even a little angle will be noticeable. Sorry to be less than techie on this one. I really don't know. I just know that an angled shaft is not only NOT a far-out idea, it's actually better. Investigate his before I go down to the boatyard and let me know! JC 2
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