Bennet Trim Tab won't bleed

HawaiianHooker

Seaman Apprentice
Joined
Aug 23, 2005
Messages
41
I got some air in the line of my Starboard trim tab and now I cant get it to bleed out. I've tested it at the motor and fluid comes out when hitting the switch but that trim tab wont fill up with fluid.

Any suggestions?

HH
 

Tabman

iboats.com Partner
Joined
Feb 21, 2002
Messages
566
Re: Bennet Trim Tab won't bleed

HH,

How old is the system? Bennett Trim Tabs are self bleeding and running them up and down 3 -4 times will automatically purge any air from the system.

Was one of the actuators recently replaced?

If you swap the hydraulic lines at the pump side to side does the problem change sides or stay on the same side?

Let me know and I will be delighted to help you get them running properly again.

Tom McGow
Bennett Marine
 

HawaiianHooker

Seaman Apprentice
Joined
Aug 23, 2005
Messages
41
Re: Bennet Trim Tab won't bleed

Awesome Tom!

The system is as old as the boat which is a 1999

It's still original afaik, no actuators replaced

I did as you suggested, switched the hydraulic lines and the problem moved to the other tab!

Note: The actuators turn on when I hit the switch, they appear to be getting 12v. The problem side does make a different noise (almost like fluid is filled and it cant pump any more) when hitting the switch.

Thanks!

HH



HH,

How old is the system? Bennett Trim Tabs are self bleeding and running them up and down 3 -4 times will automatically purge any air from the system.

Was one of the actuators recently replaced?

If you swap the hydraulic lines at the pump side to side does the problem change sides or stay on the same side?

Let me know and I will be delighted to help you get them running properly again.

Tom McGow
Bennett Marine
 

Tabman

iboats.com Partner
Joined
Feb 21, 2002
Messages
566
Re: Bennet Trim Tab won't bleed

HH,

OK, that information helps a lot.

Here is a video covering the system and troubleshooting.
http://www.bennetttrimtabs.com/videoplayer.php?vID=10

Here is a video that covers one side not working.
http://www.bennetttrimtabs.com/videoplayer.php?vID=15

It sounds as if you might have a switch or wiring fault.

At the end of this post you will find troubleshooting you can print and take to the boat. Step 3 will isolate the problem, make sure all the screws on the back of the switch are clean and tight (even if there is not a wire attached to them) and look closely at the green wire connections since it controls the starboard Trim Tab. Check the connections at the pump too. Also given the age of the system do step 6 to see if there is a relay back by the pump.

Let me know what you find and I will be delighted to help.

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).
 

HawaiianHooker

Seaman Apprentice
Joined
Aug 23, 2005
Messages
41
Re: Bennet Trim Tab won't bleed

Thanks Tabman!!!!

I finally was able to spend some time on this and as I was removing the wires from the switches to perform the troubleshooting procedures you described and found one wire with a little corrosion, cleaned them all up and the tabs are working great now..

Thanks again!

---HH
 

Tabman

iboats.com Partner
Joined
Feb 21, 2002
Messages
566
Re: Bennet Trim Tab won't bleed

HH,

Outstanding! I am delighted we could help!
 

JEBar

Chief Petty Officer
Joined
Aug 4, 2012
Messages
462
Re: Bennet Trim Tab won't bleed

found one wire with a little corrosion, cleaned them all up and the tabs are working great now..

Thanks again!

---HH


reading threads such as this one make me glad we chose to go with Bennett Trim Tabs .... our system is still in the box and won't be installed for another few weeks but it is very reassuring to know that quality customer service is available

Jim
 
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