Trojan Boat Forum

I knew this going in when I purchased my boat. My trim tabs are inop. They dont work at all. I believe the system to be original to the boat, and appears to just have stopped working . All the components visually appear to be in good condition. So I would like some input on where to begin diag on this system. I have not so much experience with the basics, so if anyone has any info on where to start , that would be great, like what to look for first. What I can tell you is that it does nothing, both rocker switches are there and the system appears to be full of hydro oil the rams seem to be clean and all connected etc. There is no clicking, no attempt to operate, as if there is no power at all to the system, which is what I think it is, but I dont have a schematic so would just have to stumble through the diag. Any help would be appreciated

which system do you have ? pic's ?

As Tony asked...what system?

If you have no power to the rocker switches and your breaker is not tripped, here's something that you may want to look for. There' a chance that there is an in line fuse between the breaker and the rocker switches. (usually close to the rocker switch) This is not the best way to wire trim tabs into a boats system however it is the way that mine was when I purchased the boat.

Pics would be great, but regardless of what system it is, the rocker switches operate a hydraulic pump which you should be able to hear when you operate the switch. If you don't hear the pump, it is not getting power or is bad. That would be the first thing I would do is see if the pump is working.

Trim tab system is very simple, but have to figure out is the problem electical or hydraulic.

symptoms.

Mine actually became unplugged at the pump which is up under the aft hatches at the transom kind of near where you add air to the stealing system.

Then I had a cut in my starboard hose right near the water line. I was wondering where that slick was coming from m

I would double check all connections then test your pump.

Good luck.

You may have Bennett Trim Tabs on your boat. But some that age were also equipped with Boat Leveler brand Trim Tabs. The way to tell is if there are exposed hoses for the actuators (rams) on the transom they are Boat Leveler. Bennett Trim Tabs usually do not have exposed tubing visible on the transom.

These pictures show the differences in the two systems:
Bennett Trim Tab

Boat Leveler Trim Tab

Bennett and Boat Leveler Pumps

Here is troubleshooting for Bennett
The first thing to check will be the 20 amp fuse if there is not a dedicated breaker for the Trim Tabs . It should be within a foot or so of the switch and should be on an orange wire. The second thing to check is to make sure both ends of the black ground wire at the pump are clean and tight.

Here is a basic diagram of the system;



Here is a link to a video that covers how the system works and troubleshooting http://www.bennetttrimtabs.com/videoplayer.php?vID=10
This video covers "No Noise From The Pump" http://www.bennetttrimtabs.com/videoplayer.php?vID=13

Below you will find troubleshooting you can print and take to the boat. Step 3 is a good place to start. Also given the age of your Trojan, check step 6 too.

Let me know what you find and I will be delighted to help you get them functioning properly.

Tom McGow
Bennett Marine

Fluid: Automatic Transmission Fluid (ATF) any type. Hydraulic Power Unit is self bleeding, running the Trim Tabs up and down 3-4 times will purge air from the system.

Fuse: 12 volt system use 20 amp in-line fuse on positive. (24v & 32v use proportionately smaller)

Red= Port Valve
Green= Starboard Valve
Blue=Motor Forward (pump pressure)
Yellow= Motor Reverse (pump retract)
Black on HPU=Ground
Orange on Helm=Control Positive

Troubleshooting

1.If one side is not operating reverse hydraulic lines on the front of the Hydraulic Power Unit to determine if the malfunction is in HPU or actuator / hydraulic lines. If after reversing the lines symptom shifts to the other side the malfunction may exist in HPU. If the symptom remains on the same side, malfunction may exist with the actuator / hydraulic lines

2. Is the unit receiving a solid 12 volts? Low voltage will some times cause the solenoids to not open preventing the tabs from moving even though the pump motor is running.

3. Conduct the following test:
Remove the wires from the helm control and touch together as follows:
Operation=Reaction
Orange (+), blue, red= Port trim tab down
Orange (+), blue, green=Starboard trim tab down
Orange (+), blue, red, green= Both trim tabs down
Orange (+), yellow, red= Port trim tab up
Orange (+), yellow, green=Starboard trim tab up
Orange (+), yellow, red, green= Both trim tabs up

If the trim tabs function correctly for each wire grouping then the switch is at fault. Also note that any loose or missing screws on the back of the switch (whether a wire is connected there or not) can cause the pump to malfunction.

This test may also be done right at the pump by substituting a "hot lead" for orange. There is usually a connector to the wire harness within a foot or so of the pump. You want to check this connection for corrosion. You may wish to cut the connector off on the pump side and try the test on bare wires.

4. If you suspect corrosion on the wire connector near the pump, cut it out, test as above and reconnect using butt splices.

5. If you conclude the problem is in the pump, contact me. Bennett Trim Tab Systems carry a five year warranty.

6. Check to see if there is a relay in line on the wiring harness near the hydraulic power unit. If there is it is an Interrupter Relay (IR1000). It prevents the system fuse from blowing if you try to actuate one trim tab up and the other down at the same time. After you test as outlined above, try removing the relay from the wiring harness and retest the unit.(Note: the interrupter relay is no longer used in current Bennett Trim Tab systems and has been replaced with a Switches that "lock out" preventing a blown fuse).

If they are Boat Leveler this should help

Here is a link to their website http://www.insta-trim.com/

I can't find any troubleshooting on their site.

The Boat Leveler system is pretty easy to troubleshoot. I put together this troubleshooting based on how the system works. If you hear the pump running but the Trim Tabs are not moving, check to see that the system is getting good power as low voltage can cause the motor to run but the valves may not open. Clean the connections and pay particular attention to both ends of the ground wire at the pump. Then do the test below.

Here is the wiring for Boat Leveler.


green=Port Valve
white= Starboard Valve
red=Motor Forward (pump pressure)
yellow= Motor Reverse (pump retract)
black on HPU=Ground
red on Helm=Control Positive





Here is how you can test it.

Remove the wires from the helm control and touch together as follows:

Operation=Reaction
(+), Red, Green=Port trim tab down
(+), Red, White=Starboard trim tab down
(+), Red, Green, White=both trim tabs down
(+), Yellow, Green=Port trim tab up
(+), Yellow, White=Starboard trim tab up
(+), Yellow, White, Green=both trim tabs up

If the trim tabs function correctly for each wire grouping then the switch is at fault. Also note that any loose or missing screws on the back of the switch (whether a wire is connected there or not) can cause the pump to malfunction.

This test may also be done right at the pump by using a hot lead. There is usually a connector to the wire harness within a foot or so of the pump. You want to check this connection for corrosion. You may wish to cut the connector off on the pump side and try the test on bare wires.

If you suspect corrosion on the wire connector near the pump, cut it out, test as above and reconnect using butt splices.

Make sure to check both ends of the black ground wire at the pump for corrosion.

wow.... thank you so much for all the outstanding info and schematics .
with this info I will be certain to get to the problem
I will keep you informed
thanks again

guglielmo6160 wrote:wow.... thank you so much for all the outstanding info and schematics .
with this info I will be certain to get to the problem
I will keep you informed
thanks again

Here is the Boat Leveler Layout:


I forgot to add it to my last post.
Tom
Bennett Marine

Hey Moderator,how about making a 'sticky' for all of this trim tab info supplied by 'Tabman'? Would be a lot easier on us to locate when needed. Thanks Moderator and a huge thankyou to Tabman!

Hey Moderator,how about making a 'sticky'

I second the motion. Tons of good info here, from someone named Tabman no less!!! Great effort Tabman.

Boat leveler offers a new water proof switch set in exchange for the old ones. The old one could get stuck on and burn out the windings on the electrical hydraulic solonoid valve. That was what was wrong with mine a clue was the bottom station set of tab switches were removed. My guess the PO moved them to the top where the old ones failed due to exposure to water and elements. I replaced the top one with the new switches and put the old ones back in the cabin. purchased a new hydraulic actuator.

Allen Sr wrote:Hey Moderator,how about making a 'sticky' for all of this trim tab info supplied by 'Tabman'? Would be a lot easier on us to locate when needed. Thanks Moderator and a huge thankyou to Tabman!

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