Indigo prop final check

paul culver

Member III
I'm about to replace my 2 blade factory prop with the indigo 3 blade and hoped that anyone with a bad experience could chime in before I pull the trigger. Of course I'll be happy to hear any endorsements as well.

Thanks
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Another thread that mentions it.
 

garryh

Member III
I have one not yet installed because I need to upgrade the shaft from 3/4 to 7/8. But a buddy with a C and C 35 with an A4 replaced his two blade with an Indigo three blade and said the difference in power and control was night and day.
 

tenders

Innocent Bystander
If it’s worked this long...why worry about it? Plenty of A4s were installed with 3/4” shafts. BTW I have a Moyer 3/4” split coupling that I need to sell - THAT is a worthy upgrade, except unfortunately it won’t fit on my V-drive.
 

garryh

Member III
"If it’s worked this long...why worry about it? "
Because things break in time, especially those under-spec'd. I would rather not wait for that to happen.
I am not an engineer so I cannot speak with any authority. But my previous boat was a P30 with the same engine and same era and had a 7/8 shaft.
Friends with a Catalina 30 a few years newer with an A4 have a 1" shaft. Those boat manufacturers would have used 3/4" if they thought it was fine.
A 3/4 shaft just seems dinky. I will replace it when the job comes nearer to the top of the list.
 

tenders

Innocent Bystander
3/4” shafts are not breaking in Atomic Four installations. Shaft specification is a well-documented corner of engineering, and I‘m pretty sure the Ericson engineers knew what they were doing, especially by 1978. My ‘69 32 has a 3/4” shaft, and I’ve replaced it twice in 30 years of ownership - neither time had anything to do with it being broken or underspecced. (The second time was this afternoon, due to a failed shaft seal.) You might reconsider once you see how much parts, labor, and yard time will be involved to replace a perfectly good coupling, shaft, strut, Cutless bearing, and propeller.
 

garryh

Member III
as mentioned above, my P30 had a 7/8 shaft, my friends Cat30 has a 1" shaft... even C and C 27's with A4 have 7/8 shafts, and those companies also have engineers. Ericsons are generally well designed and well built boats, but they were not immune from the occasional cost cutting shortcuts. The rudders on the 35ll were one notable example, using the rudder from the 32 apparently... which is at least one reason why these boats are virtually uncontrollable in reverse. Also, the mounting of hardware, chainplates etc through cored deck which has caused such huge issues later on.
So if not under-spec'd, 3/4 shafts might be at least marginally spec'd
There is no yard time, the boat is in the yard; there is no labour cost, I will do it myself; the cutless bearing is not perfectly good as it requires replacement anyway; the strut is perfectly good and will remain, the new cutless bearing will have the same OD but 7/8 ID; and the propeller is the 7/8 Indigo that I want to put into use. I simply need a new shaft for a couple hundred dollars, which to me is money well spent.
''Still working so leave it'' is rarely a good reason to not do something. My chainplates look fine and are still working, but are 40 years old and I will replace them. My stays are still fine, but 40 years old so I will replace them. The same logic can be applied to a marginally spec'd 40 year old SS shaft. One does not wait for any of these things to break before one replaces them because, if they do go, they can ruin your entire day.
This is simply another 'your boat, your choice' kind of thing.
 

Parrothead

Member II
In support of Garry's comments and at the risk of offending the Ericson faithful, I have read on this and other forums of the general opinion among many Ericson owners that their boats are of superior quality compared to their competitors. From considerable experience in boat construction, repairs and modifications across a wide spectrum of boat brands, the truth is Ericsons are not that different from most others. They are made with the same materials from the same vendors with similar construction techniques by the same labor force and share many of the same long term problems. Re: labor force, the same people made the employment rounds from brand to brand. Many of the guys I knew at Columbia/Coronado, Capital (Newports), Jensen (Cal, Ranger, O'Day, Luhrs and DeFever) and Islander also worked for Catalina, Schock, Sam Morse (Bristol Channel Cutter), Pacific Seacraft and Westsail at one time or another.

As for the prop shaft, while it's true that Ericson used the smallest diameter in the industry, failure reports are non existent.
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
One of my diesel mechanic friends told me that one reason for the change to 1" shafting in the late 70's for most builders was the upgrade to diesels from the earlier and very common gas engines. He sez that the combustion shock of the more powerful 'stroke' of the diesels put more torque on the shafting. Similar, IMHO, to the reason for the "torque plate" between the engine and the transmission, to soften the shock to the gears.

Having spent days at a time on a boat with a single cylinder diesel, and also spent hours on an older boat with a small gas twin, I do recall the difference in smoothness. It's very noticeable.

As for differences in the higher-end boats, the raw materials and labor were certainly similar, but the engineering was rather different. I would cite the hull/deck joint in the Ericson's as an important one. Tabbing the bulkheads in the 80's, was another. Note that many of the important differences are not visible to any casual inspection, and cheaper-built boats always had (and have) the most sales. There is always a "Gresham's Law" effect, as in many industries.
it is what it is......
 
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