hydraulic tab questions

[bones774]

Im looking at buying a cobalt bow rider and believe the tabs are not working.
The boat has the original cobalt installed tab switches plus owner added Bennett smart tabs sysytem which he acknowledges does not work(no power indication at all). The cobalt installed system I can hear run but the tabs do not appear to move, I have tested them manually and they are not stuck, they extend when pushed down and retract fully when let go, so the pistons can't be stuck. It's my first boat, maybe they need fluid? What type? Is the bennett system better and should i fix it? If I have bennet and cobalt systems will there be 2 hydraulic units? although one not hooked up? Thanks

 

[rbh]

Re: hydraulic tab questions

time to have a good look and see what you have in the engine compartment because you just dont know what the other guy has done.
rob

 

[dingbat]

Re: hydraulic tab questions

Chances are it's a Bennett switch with the Cobalt name stamped on it.

The auto tab switch is a direct replacement for the standard tab control switch. There would have been no reason to install a second hydraulic power pack to make the system operational.

The fact that you can move the cylinders by hand tells me you?re out of fluid or the lines are disconnected from the power pack.

The unit takes "any type" of power steering fluid (ATF)

 

[bones774]

Re: hydraulic tab questions

What is odd is that the bennett system was installed afterwards yet the OEM installed system is the one that has power. So why install aftermarket and then return to older original install?
I'll check fluid hope that solves the problem, but is 200 miles away right now, though.
Thanks

 

[dingbat]

Re: hydraulic tab questions

What is odd is that the bennett system was installed afterwards yet the OEM installed system is the one that has power. So why install aftermarket and then return to older original install?
I'll check fluid hope that solves the problem, but is 200 miles away right now, though.
Thanks

The auto tab control is nothing more than a black box and controller switch that gets attached to the existing system. I would imagine that the black box went out on him and instead replacing it ($400) he just reverted back to the stock system.

 

[bones774]

Re: hydraulic tab questions

OK, I got back to boat and filled the reservoir to the line , it was pretty empty. The motor got much quieter, and trim tabs did not work, check for pulsing of hydraulic lines during motor on and there was some pulsing, when manipulating the tabs manually and switching at same time , they worked intermittently, did not observe any leakage.
Sound like new motor needed? Is there some check valve or rebuild kit for motor? Just get new motor?
The motor is pretty simple it is a oblongish blue motor with reservoir on bottom, two screws to transom, a hyd line exiting right and left and power connection.
Thanks

 

[marine4003]

Re: hydraulic tab questions

as with car brakes, you may need to bleed the system, before you buy another pump try bleeding first.

 

[bones774]

Re: hydraulic tab questions

I was thinking that also, but from all I read they are sefl purging. I have been operating the boat and switching the tabs on and off in the hopes of purging the air out.
Thanks

 

[skargo]

Re: hydraulic tab questions

Bennetts are self bleeding by cycling them, no need to bleed them, this is according to Bennett themselves.
Contact them, their customer service is second to none.

Here is the troubleshooting procedure from Tom at Bennett.

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. We also offer a trade in program for units out of warranty. Contact us for further details after you troubleshoot the system.

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. If it works the IR1000 will need to be replaced

 

[dingbat]

Re: hydraulic tab questions

I was thinking that also, but from all I read they are sefl purging. I have been operating the boat and switching the tabs on and off in the hopes of purging the air out.
Thanks

The pump motor either works or it does not. If you can hear the motor running its working and does not need replaced.

The tabs are self bleeding but there is a procedure to follow

Using the switch control, press the "bow down" position and hold for 15-20 seconds. Listen to the pump. The pump will squeal until it purges all the air from the line. Press the "bow up" switch and hold 15-20 seconds. Listen to the pump. Do this 3-4 times on each switch or until the squealing should stop.

If the squeling doesn't stop you have a leak somewhere in the system. Check the connection at both the pump and the fitting where the line passes thru the transom and connects to the back of the trim cylinder. Check to make sure the tubing has not been damaged and needs replaced

 

[bones774]

Re: hydraulic tab questions

The bennett trim tabs have been removed and just the switch is there, so it's not Bennett. Inspection reveals it is a Boat Leveler Insta-trim unit. I don't think it's electric because you can hear the motor when you cycle the switches. Someone earlier said if you hear the motor "it's working", the trim tab rams move freely when manually moved, I don't see any fluid leakage and I would imagine that oil leaking in the water would be observable. Any ideas??

 

[dingbat]

Re: hydraulic tab questions

The bennett trim tabs have been removed and just the switch is there, so it's not Bennett. Inspection reveals it is a Boat Leveler Insta-trim unit. I don't think it's electric because you can hear the motor when you cycle the switches. Someone earlier said if you hear the motor "it's working", the trim tab rams move freely when manually moved, I don't see any fluid leakage and I would imagine that oil leaking in the water would be observable. Any ideas??

The quickest way to rule out a leak is to check the fluid level in the pump. Is it still full?


The pump is running but you might be picking up the valve ports. Test per the following:

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.

 

[bones774]

Re: hydraulic tab questions

I'll put some jumpers together and do the wiring test this weekend. Thanks

 

[rs1lollie]

Re: hydraulic tab questions

is there any relief valves or pressure adjustment screws?? kinda like what they have on outdrive trim pumps??? just my 2cents.

 

[bones774]

Re: hydraulic tab questions

i don't see any adjustments and the insta trim site does not mention any either.

 

[dingbat]

Re: hydraulic tab questions

is there any relief valves or pressure adjustment screws?? kinda like what they have on outdrive trim pumps??? just my 2cents.

No there are not

 

[skargo]

Re: hydraulic tab questions

The quickest way to rule out a leak is to check the fluid level in the pump. Is it still full?


The pump is running but you might be picking up the valve ports. Test per the following:

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.

Is there an echo in here?