Pair of DF175s

[marine_angler]

Hello. I'm new to this forum. I bought my current boat (2000 Glacier Bay 26' center console with twin 2009 Suzuki DF175's) last September and have ran her roughly 120 hours since. Nothing but great things to say about these engines. We offshore fish here in Texas which means LONG runs so reliable motors is number one priority (reason for wife making me sell previous boat with Optimax's...they were anything but reliable).

The previous owner had these massive hydro-foils (Nedski foils) installed on each of the motors to act as trim tabs since catamarrans cannot utilize trim tabs. I have to admit that they worked pretty nice but I noticed that one of the foils was cracked (port motor) and the starboard motor's cavitation plate on the gear case is cracked so I removed the foils this past weekend. The amount of damage to the gear cases as a result of these foils makes me sick to my stomach. They had to drill roughly 20 or so holes in each of the cavitation plates to install these things. Lots of corrosion and I assume more to come unless I get pro-active (which is why I'm on here).

Are these gear cases (lower units) made from aluminum? If not, does anyone know what metal?

First thought was to replace the housings but based on that cost, I plan to use a torch and raw metal to fill in the holes, then repaint the damage. For the starboard's I plan on doing the same but also add a bead of weld on the top of the cavitation plate rather than from the bottom (may need to do from both sides).

Does anyone have any experience on something like this? Thanks in advance.

Thomas

[noelm007]

Yes the gear case is alloy, but I don't think I would be going to attempt to fix it with "a torch" TIG welding would be the preferred tool for the job. By the way, Catamaran hulls to do need trim tabs, the motors can be trimmed individually to compensate for sideways trim, the foils were probably fitted to cover some other problem.

[Solarman]

cavitation plates

Yes they can be welded, but by someone that knows how to weld aluminum / heli arc. Contact a machine shop that knows how to weld aluminum.they can repair the holes. Just like they repair the fins/ skegs under the prop when people drag the motor on pavement.

[kurttruk]

you can put tabs on a cat. most tab manufacturers already know what you need they just don't advertise them. they can do custom tabs to fit what you need. I like the tig welding idea or JB weld. Something hard that wont corrode. Dissimiliar metal corrosion would be my worry with the welding.