bertram31.com

In the process of putting in 250 cummins/ was going to use the original struts if possible-need to be machined for 1.5 inch shafts.
However when i received the boat the struts were already removed and was wondering if they were the original ones, any way to tell. The struts have 4 holes that are square. The vintage of the boat is hull eary 60's #161
Thanks

Spencer

Originals have 6 holes...

And the originals are faired to a knife edge on the leading edge My originals were cracked during Katrina and I got new ones from Hi Tide that are massive - the leading edge is rounded and very thick. Capt. Patrick warned me to have the leading edge ground down or I'd lose some speed. I instructed the yard to do it but of course they forgot and the boat was already in and I was assured they had ground them down, but no mention on the huge bill. They lied. Cost me close to a knot. One of these days I'll take a grinder to them, but Howdy Boating is a low speed enterprise anyway.

UV

Thanks for the info

I called high tide
Waiting for him to call back
Looks like the ones I have are from another boat
Glad I figured it out before I had them machined

Thanks

Spencer

Spencer...

I just sanded all my running gear down to bare metal prior to bottom painting. When I sanded the inboard surfaces of both struts I found a rectangular depression in the casting with the word "Bertram" and a number. My boat is a B33.. I am not sure if B31s have this, but I am sure someone else here would know.

Spencer

When I had my struts cleaned up during my repower they were marked Bertram also. If they don't say Bertram they are not original.

Spencer,
When I looked at your boat awhile ago I remember the struts were not original, they were not from a 31 I made a mental note when I saw them.

The original struts do have six carraige bolt head bores and a tappered leading edge. I had my struts cast at Buck Algonquin when I re-did the bottom, both of the old struts were almost paper thin around the barrels were the cutless bearings had been. When I had the new ones made they made the barrels area with more meat and they can be bored out to 1-1/2 if need be. Mine were low profile struts only 9-1/2" to the center of the shaft and I have a set of intermediate struts just aft of the shaft log tube. I have a very flat angle shafting, I get on plan alot quicker than most 31's, the only draw back is I can only turn a 18" diameter prop and still hqve room for clearance on the bottom to prevent cavation burns onthe hull bottom. You need a 1-1/2" of clearance between the prop blade and the FRP bottom.

Pete,
Do you think it's best just to get high tide struts,
Or get custom ones made?
High tide was about 800$
Per strut with cutlas bearing for 1 1/2 shaft

Original or not, as long as they are in good shape, fit correctly and build to withstand the extra torque...is there room to bore them out to 2" for your 1-1/2" Cutless Bearing?

If you want and extra set of holes to mount struts...mark where you want them and have them drilled out when machining the bores open.

If your buying aftermarket or having custom made...they are not going to be originals, so whats the point?

Sim

The bases on the struts I have are more square and less rectangular than the original. ( was concerned about strength) I want to keep the strut angle close to original and I did not want to guess if the ones i have are the right angle or not. They also would have to be bored out to fit larger shafts. If they were from bertram I would use them but being they are not I would rather fabricate or buy aftermarket with the correct shaft size/angle.

I think the only thing left on the boat original will be the hawse pipes, side steps, hull and bow chock. Which need to be rechromed.

Spencer,
Like Sim said if there is enough meat at the cutlass bearings and they look like they would hold up for the 1-1/2" shafts I'd use them, they aren't original that's for sure. Just make sure there are no cracks in the castings( sand they down to bare metal and use a magnifying glass look very close at the barrels, the top flange and where the metal meets the barrell.) Also sight down the lenght of the strut fore and aft for bends. The usual struts on the 31' were about 13" to 15" in height. The low profile one 's were only 9-1/2". If they are suspect in any way buy new ones, you might want to check with Stuart Prop for pricing either bronze or stainless will be fine.