trim tab not working.

seasalt1964

Cadet
Joined
Feb 12, 2011
Messages
12
Hi
One trim tab is not working on a bayliner 285. The boat is a 2006 that was out of the water for 4 years . 1 side (port) works ok but the starbord motor just wirls away.. Any ideas were to look ??? Thanks in advance..:)
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: trim tab not working.

hi....welcome to iboats !

the trim tab has just one motor.....so if one side works....the motor (or pump) works.....

the problem will be in the ram attached to the tab....look for leaking oil around the cylinder
 

tpenfield

Moderator
Staff member
Joined
Jul 18, 2011
Messages
17,706
Re: trim tab not working.

Hi
One trim tab is not working on a bayliner 285. The boat is a 2006 that was out of the water for 4 years . 1 side (port) works ok but the starbord motor just wirls away.. Any ideas were to look ??? Thanks in advance..:)

I have been through several bouts of trim tab issues. Each time when I thought it to be a hydraulic problem, it turned out to be an electrical problem (doh !!!).

As Oops said, there is one motor, but there are 2 valves. Chances are that there is a poor/loose electrical connection for that starboard side. Check the connector near the trim tab pump, and if need be, check the connections to the switch(es) at the helm.
 

Tabman

iboats.com Partner
Joined
Feb 21, 2002
Messages
566
Re: trim tab not working.

Seasalt1964,

Bayliner installed both Bennett and Boat Leveler brand Trim Tabs. Can you tell me if you know what brand yours are?

I believe they are Bennett so here is the troubleshooting for them:

Here is a link to a video that covers the basic system and general troubleshooting http://www.bennetttrimtabs.com/videoplayer.php?vID=10

Here is a link to a video that covers troubleshooting if one Trim Tab does not move http://www.bennetttrimtabs.com/videoplayer.php?vID=15

Take a look at step 3 below, it will walk you through the test I think will isolate your problem. Also pay particular attention to the Green wire since it opens the valve for the Starboard Trim Tab. Make sure that all of the screws on the back of the switch are clean and tight, even if they don't have a wire connected to them.

Let me know what you find and I will be delighted walk you through fixing it.

Tom McGow
Bennett Marine

sys.jpg


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).
 

seasalt1964

Cadet
Joined
Feb 12, 2011
Messages
12
Re: trim tab not working.

I managed to get the starboard tab working , sort of ... I cleaned all the electrical conectors , took the solenoids out and inspected them and topped the fluid up . THe tab worked first time to full down position . but slowly raised itself. Turns out there is a fluid leak where the hydraulic line leaves the pump. All is nice and tight so might need to replace the line
 

seasalt1964

Cadet
Joined
Feb 12, 2011
Messages
12
bennits trim tab woes ( bayliner 285)

bennits trim tab woes ( bayliner 285)

Hi
I posted a few weeks ago about a trim tab problem which after some great advice i found an oil leek, so i ordered a new part , All of ?3.50 posted :D.

After fitting the new part and stopping the oil leek the problem is still there. The starbord tab deployes all the way down but then slowlly returnes to the up position on its own. I have noticed if you put your hand on the tab you can feel a slight pulse as it slowlly returns to its up position .. The system has been blead and the port tab works fine.

Any ideas were to look now :confused:



Martin
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: bennits trim tab woes ( bayliner 285)

Re: bennits trim tab woes ( bayliner 285)

im guessing here....there still might be air in the system.
 

cyclops2

Banned
Joined
Apr 19, 2011
Messages
1,237
Re: bennits trim tab woes ( bayliner 285)

Re: bennits trim tab woes ( bayliner 285)

Solonoid O ring leaking or preventing full pressure due to not being able to fully open & close.
Cylinder with 1 or 2 bad O rings. Same problem.
Piece of a O ring stuck or drifting in & out of a opening.

I check these cuties with a 5 gallon pail & the cover ON tightly. I remove the good cylinder hoses 1 at a time then pressurize the hose. Remember how HARD / Fast oil comes out.
Do the same tests on the bad side.

I would spray clean VERY CLEANLY all the fittings I am going to remove. HAVE CLEAN FLUID TO REFILL WITH !!!!
DO NOT RISK specks of crap comming off the hose & then dump that back into the pump & system.

You will see a difference ??? If not, you KNOW IT SHOULD REALLY BE THE CYLINDER. Old, rebuilt or new.
 

Tabman

iboats.com Partner
Joined
Feb 21, 2002
Messages
566
Re: bennits trim tab woes ( bayliner 285)

Re: bennits trim tab woes ( bayliner 285)

Martin,

Do you actually see a fluid leak at the starboard actuator (ram), lines or at the pump. If not then the valve seat in the starboard solenoid is damaged or fouled. This will allow the fluid to bypass back into the reservoir and the Tab will retract as pressure is lost.

Take a look at this video, it shows how to inspect and replace the valve seat. http://www.bennetttrimtabs.com/videoplayer.php?vID=16

How old is the system and where are you located?
 

seasalt1964

Cadet
Joined
Feb 12, 2011
Messages
12
(still) ongoing bennett trimtab woes

(still) ongoing bennett trimtab woes

The plot thickens, starboard trimtab deploys then slowly returns with a pumping motion felt when toutching the tab. There are no oil leeks. I have cleaned the solenoid and replaced the valve seats and seals with new ones . I have also swapped solenoids over . Still the starboard one comes back up. The port tab works fine with eather solenoid...

I am begining to think there is black magic or something at work ,becouse i am at a loss....

Oh yeh i have also thourally inspected the electrics ????????

Also the whole system was on dry land from 2008-2011 on a 2006 boat and only had 30 hrs when she was put back in the water and the problem discovered ....
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,524
Re: (still) ongoing bennett trintab woes

Re: (still) ongoing bennett trintab woes

Ayuh,... My guess is the starboard actuator cylinder is corroded/ crudded up...
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,498
Re: (still) ongoing bennett trintab woes

Re: (still) ongoing bennett trintab woes

If one tabs works on both pump outputs, then it is obvious that you have an issue with the one tab.
Remove the tube running from the pump to the tab in question at the actuator end. If the tabs moves up and down with ease you have a pinched or blocked tube. If the tab still does not move freely you have a stuck actuator.
 

Tabman

iboats.com Partner
Joined
Feb 21, 2002
Messages
566
Re: (still) ongoing bennett trintab woes

Re: (still) ongoing bennett trintab woes

Seasalt1969,

In your last post about the Trim Tabs, http://forums.iboats.com/showthread.php?t=538035&p=3682204#post3682204 I posted the following on March 23rd;

Martin,

Do you actually see a fluid leak at the starboard actuator (ram), lines or at the pump. If not then the valve seat in the starboard solenoid is damaged or fouled. This will allow the fluid to bypass back into the reservoir and the Tab will retract as pressure is lost.

Take a look at this video, it shows how to inspect and replace the valve seat. http://www.bennetttrimtabs.com/videoplayer.php?vID=16

How old is the system and where are you located?




Did you get a chance to view the video and inspect the valve seats. Unless you removed the valve seats and swapped them when you swapped the solenoids, the problem would stay on that side. After reading your latest description I am 99% certain that replacing the valve seat will solve your problem.

Please get back to me so we can get this fixed.
 

seasalt1964

Cadet
Joined
Feb 12, 2011
Messages
12

seasalt1964

Cadet
Joined
Feb 12, 2011
Messages
12
Re: (still) ongoing bennett trintab woes

Re: (still) ongoing bennett trintab woes

Seasalt1969,

In your last post about the Trim Tabs, http://forums.iboats.com/showthread.php?t=538035&p=3682204#post3682204 I posted the following on March 23rd;

Martin,

Do you actually see a fluid leak at the starboard actuator (ram), lines or at the pump. If not then the valve seat in the starboard solenoid is damaged or fouled. This will allow the fluid to bypass back into the reservoir and the Tab will retract as pressure is lost.

Take a look at this video, it shows how to inspect and replace the valve seat. http://www.bennetttrimtabs.com/videoplayer.php?vID=16

How old is the system and where are you located?




Did you get a chance to view the video and inspect the valve seats. Unless you removed the valve seats and swapped them when you swapped the solenoids, the problem would stay on that side. After reading your latest description I am 99% certain that replacing the valve seat will solve your problem.

Please get back to me so we can get this fixed.

Yes that was my post.

There are no fluid leaks , there was a leak coming from the brass nut that connects the fluid hose to the pump but that has been resolved with new parts. and there are no fluid leak anywere to be seen. i have also replaced the valve seat and seal with new ones today ,same problem . The only difference is the tab stayes down for about 30 seconds then comes up .. if i swap the solanoids around the problem stays . I have not swapped the valve seats and seals around as i have fitted new ones.

The system is on a 2006 bayliner 285 , but the boat was out of the water from 2007-2010 and only had 30 hrs when the problem was located . the boat was on the solent at southamptom and now ont the thames in the UK
Just to make sure that i am correct in placing the piston facing down with the spring going up into the solenoid ,with the black plastic cap on the piston sitting on the valve seat. would hate to think i have made a stupid school boy error :facepalm:
 

Tabman

iboats.com Partner
Joined
Feb 21, 2002
Messages
566
Re: (still) ongoing bennett trintab woes

Re: (still) ongoing bennett trintab woes

Yes the spring goes up into the solenoid and the black "rubber" on the plunger faces downward onto the valve seat.

Well fluid is bypassing on that side past the valve seat. So let's look closer at it. First make sure that the little black quad ring is properly seated on the bottom of the valve seat. Also make sure that the side of the valve seat with the quad ring is facing down.

The quad ring is #4 in this drawing.

bennet-pump-2.jpg


If that all looks good, then very carefully inspect the inside of the valve pocket for scratches or debris.

Let me know what you find.
 

seasalt1964

Cadet
Joined
Feb 12, 2011
Messages
12
Re: (still) ongoing bennett trintab woes

Re: (still) ongoing bennett trintab woes

Thanks ,i will have a close look tomorow.
One thing i have noticed . You say 'black rubber on the plunger ' It felt more like hard plastic . Is it posible it has dried out from not being used and causing the problem ??
 

Tabman

iboats.com Partner
Joined
Feb 21, 2002
Messages
566
Re: (still) ongoing bennett trintab woes

Re: (still) ongoing bennett trintab woes

It's pretty hard rubber and I have never seen it dry out, I have seen it attacked by other fluids if someone uses something other than Automatic Transmission Fluid in the system. Plus if the plunger was the problem the problem would change sides when you swapped the solenoids.
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,524
Re: (still) ongoing bennett trimtab woes

Re: (still) ongoing bennett trimtab woes

I apolagise i will keep it all in this thread in the future ...

Ayuh,... I merged all 3... Hopefully it don't read to funny now...
 
Top