Luhrs 290 (1997)

I don't see how that's possible unless someone gets too ambitious with the trim tabs. I've run several boats that track very well, and the result is that you can steer the boat well with just the tabs but giving too much tab can surprise the helmsman. If it were a constant list I'd say add ballast, but just at high speed just be gentle with the tabs.

THT is full of bad info. I run a 2002 290 Open. I tracks well at up 28 knots at 3800 rpm on the Yanmar 315s. After some damage to my tabs by hurricane Sally, I discovered that Luhrs used an OEM version of the trim tab actuators and confirmed this with Bennett. They retract the piston fully into the actuator instead of 1" extension at fully retracted and extend 3.5" instead of the standard 2.5". This yields about 2.5" of extension from the pocketed tab full closed position. I suspect many of those so called squirrelly boats may have had a typical 2.5" actuator installed as a repair by an uninformed mechanic.

As NYCAP123 says, be careful with the tabs at high speed, she reacts fast!

Rob
2002 Luhrs 290 Open "Tres Leos" 6LPA-STP Yanmars
1986 Tiara 3600 Continental "Southern Exposure" 7.4L Crusaders

These are Bennett classic V351 hydraulic trim tabs. I am still not positive this is the actual actuator part number. I had one actuator that would fully retract into the cylinder (about 1/2" of the piston with the hinge pin hole showing is all that extends) and extend 3.5" and one that seemed to be a standard actuator with the upper spacer removed, but only extending 2.5". I removed the spacer in upper hinge ends to insure the trim tabs pulled up tight against the hull pocket edges even though it appeared 1" would be correct because one spacer had obviously been cut about to 1". I cut the 4.5" bottom sleeve to 3.5" on the one with the long spacer, making it meet the specs below. Here is what I noted in my maintenance book:

Recommended to use SA-2110A for 3.5" stroke. The SA2110A actuators are special in that they have 3-1/2" of stoke (1" more than the standard A1101A's), but to gain this extra stroke the Upper Hinge Spacer has to be modified by cutting it down to one inch. This also reduces the overall length of the actuators by one inch too, so they are 12-3/4" overall while the standard length is 13-3/4". The sleeve in the bottom of the cylinder stops the piston travel downward and protects the spring. The length of this sleeve varies by application. It is ~3.5" in the SA-2110A vs. 4.5" in the standard actuator. This allows the extra 1" stroke.​

These are simple devices. If you do this, get new o-rings for the piston and the upper hinge and replace them while you are in it. Bennett says to put the piston o-ring into the groove the original was removed from, not always the top ring despite instructions to the contrary you may find on the internet. Apparently there were machining tolerances that could be off in the empty groove.

Relay Module RM12​

Solenoid Valve Green Wire VP1135G
Solenoid Valve Red Wire VP1135R
-224 O-Ring (Top Hinge O-Ring) A1120
-220 O-Ring (Piston O-Ring) A1121
Long 4 Ring Actuator SA-2118-ARC 2.5" stroke or SA-2110A for 3.5" stroke

Rob

2002 Luhrs 290 Open "Tres Leos" 6LPA-STP Yanmars
1986 Tiara 3600 Continental "Southern Exposure" 7.4L Crusaders

Which is why I won't sell the Tiara or the Luhrs! Can't replace them for what I have in them buying on the open market. I am standing by for the big crash to pickup my 45+ convertible. Having the 29 is nice because she is just the right size to day fish. The Tiara is a fine base camp platform.

Rob

2002 Luhrs 290 Open "Tres Leos" 6LPA-STP Yanmars
1986 Tiara 3600 Continental "Southern Exposure" 7.4L Crusaders