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non working trim tabs

Printed From: The Fishing Website
Category: General Forums
Forum Name: The Boat Shed
Forum Description: Discuss all things boating.
URL: https://www.fishing.net.nz/forum/forum_posts.asp?TID=100501
Printed Date: 29 Mar 2024 at 8:36pm


Topic: non working trim tabs
Posted By: Buggar-me
Subject: non working trim tabs
Date Posted: 19 Apr 2014 at 5:17pm
Hi All, I have trim tabs that are lever/ Hydraulic operated. My problem is one was not working. Thought I would bleed the lines, so disconnected the line but all that happened was that when I pulled the lever down,( Each trim works on the same oil tank, but obviously separate levers), the atf fluid came back out the filler hole. Now the trim tab that was working isn't working as well.
Question is does any one in Auckland know how to fix or someone I can take it to, to get fixed?



Replies:
Posted By: Ohsoslow
Date Posted: 19 Apr 2014 at 7:34pm
Shouldn't you pull the trim tab down instead of the lever.. Use the trim tab to suck fluid into the system. Just make sure the reservoir is kept full so it doesn't suck air into the system..

Just a thought.. Might be wrong!


Posted By: Buggar-me
Date Posted: 19 Apr 2014 at 8:25pm
Tried that. didn't work


Posted By: Norseman
Date Posted: 20 Apr 2014 at 6:52am


Here is info on troubleshooting Bennet trim tabs...


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 the company. Bennett Trim Tab Systems carry a five year warranty. They also offer a trade in program for units out of warranty. Contact them 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

 

Here is the cross reference for troubleshooting Insta-Trim tabs.


Bennett Orange = Insta Trim Orange (this is positive power)
Bennett Blue= Insta Trim Red
Bennett Yellow = Insta Trim Yellow
Bennett Red = Insta Trim Green
Bennett Green = Insta Trim White
Bennett Black = Insta Trim Black (this is negative ground)

Substitute these colors in the troubleshooting and you should be able to isolate the fault in an Insta-Trim system.



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"Nothing is so strong as gentleness, nothing so gentle as real strength." St. Francis de Sales


Posted By: Buggar-me
Date Posted: 20 Apr 2014 at 8:29am
sorry forgot to mention, these are manual trimtabs. not electric. that is my problem. found plenty of info on electric. I have considered removing them all together. Will obviously affect the performance but at present doesn't make for a comfortable ride anyway because the boat always leans to the left at speed.


Posted By: Steps
Date Posted: 20 Apr 2014 at 9:11am
I had a set of those in my old Fleetline bonaccord back in the early 70s
I assume yours go back to the same era
And I had the same issues back then
1st thing with hydraulics (including non ABS brakes), like most things, do not be intimidated because once u uderstand how they work one then feels a little foolish afterwards
It sounds like u have got moisture in the oil, moisture in hydraulic/ brake fliuds  reacts to form hydrocloric acid.. and this is rather corisive to most metals.
This lays in the bottom of the bores wher the seal are and causes wear on seal and leaks past the seals in damages bores.
So pull the pistons/ seals out and inspect these..
If the bores are not to baddly pitted, run a brake slave cylinder hone down the bores till there is NO pitting
Inspect the seals for ANY slight feathering on the edges and hardening of the seals or O ring s as may be the case... thu best to replace
Most seals/ o rings , like bearings , are a std size so dont need 'orginal' manufactures

because the boat always leans to the left at speed
Using the trim tabs used to make a huge difference to fuel consumption.
Back then my old 115 Chrysler....did not have trim, so the tabs where needed.
Now with our Commander(similar boat) and modern johnson with trim and no tabs (removed them) had a similar issue that if at cruise or above would pull to one side and lean sightly.....
So went to the engine manual...
on the  rear/bottom side of the cavitation plate is a little adjustable 'skeg' thing...turning this etherway slightly stops the pull/ lean (cant rem which way does what sry)
But it doesn't do full adjustment right thru the speed range...
my thinking was this..
Adjust at a speed nearly 1/2 way between WoT and cruise speed....got it right 2nd adjustment...
At slow speed if one really concentrates one MAY feel a slight pull, I think??
Then I re proped, better grip (less slip) better overall economy (40 to 50%) and had to readjust, and this time ended up with the little skeg thingy dead center.
Aplling this data to what I have leant about proping, I make the assumption (assume because lack of experience) that if ther is excessive pull/ lean there could also be an issue with incorrect blade area. diameter of the prop.(slip)  with substantial gains to be made in overall economy

May sound strange but u may sort your hydrolic issue by correct setting of the cavitation skeg or correct propping on a engine that can be trimed.

Just a thought...


Posted By: Buggar-me
Date Posted: 20 Apr 2014 at 11:33am
thanks steps. Will try that. And by the way I have a 75hp crysler on my steadcraft. Still running well but getting harder to find a service person.


Posted By: Steps
Date Posted: 20 Apr 2014 at 2:50pm
I used to do all the service back then.. was simple old school stuff like carbs dizzies no electronic BS that need 10K worth of scan tool just to find out thats its running ok lol
Thu would imagine parts would start to be an issue now????
Did a lot of hrs with that engine.. the only things that did change was plugs and impleller outside service


Posted By: Buggar-me
Date Posted: 20 Apr 2014 at 7:12pm
I had an issue where the motor would not fire up. took it to local marine agent who told me the power pack was gone, and then tried to sell me a another motor(mercury 90hp) for 7k. jumped on here and was told it was only the dizzy. which it was. Goes fine apart from smoking at start up.


Posted By: larsandjo
Date Posted: 21 Apr 2014 at 7:35am
2 stroked smoke like **** at startup anywya!
I have a set of Blackwell Trimtabs in mint condition with levers and pumps etc which I am not using ( came off the old boat and too small for my 24ft ally )
Would sell them for 300 if interested.



Posted By: cosmo
Date Posted: 11 Oct 2018 at 3:08pm
Also have a problem with MANUAL TRIM TABS and trying to bleed them any ideas please.......wondering about compressed air to push oil thru

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i just want to go fishing..........amd ignore all my adult problems


Posted By: Tagit
Date Posted: 11 Oct 2018 at 5:40pm
Need more info Cosmo. What type of tabs and what is happening?


Posted By: Steps
Date Posted: 11 Oct 2018 at 8:18pm
The ideaif bleeding is to remove all the air. Air will compess, oil doesnt.
Tried to bleed like bleeding brakes?
Reservoir full, pump up and hold..crack line at the tab, tighten , then release lever and repeat.
 I cantr get oil to tab.
 Then repeat above except crack at the pump cylinder out let...seeif have pressure there.
 If doesnt pump up / dont get oil thru, then likely a pump seal or corrosion in the pump bore.
 


Posted By: cosmo
Date Posted: 11 Oct 2018 at 8:47pm
cheers tagit and steps they are a realold couple trims tabs and have got hold of the original guy and he said check there is pressure at the main control box and there is, so putting new atf oil in them and trying to work out how to get it past the stern and thinking i will probably have to go for height and let nature take its time and self bleed. they are on a 1 owner sea nymph prior to me it was that original it still had the 1975 70 hp chrysler on the RRRSSS and had never even had holes in the dash for gauges or anything.
the trim tabs were made by Alpha Engineering and have managed to track down the original owner and hes willing to look at them but trying to see if i can get them going first


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i just want to go fishing..........amd ignore all my adult problems


Posted By: Tagit
Date Posted: 12 Oct 2018 at 11:37am
If you get stuck put up some pics so we can see them. I don't know the Alpha tabs at all.Normally though you can crack the hydraulic connection at the ram on one side and then use the pump to push fluid through to the ram from the other side if there are two hydro lines. If only one line you need to get the ram fully retracted, then crack the connection at the ram, then carefully hold the tab in the up direction whilst someone operates the tab in the down direction until only clean fluid comes out where the line is cracked. Then tighten the line and run it up and down several times and repeat if required. .


Posted By: cosmo
Date Posted: 13 Oct 2018 at 9:16am
Cheers Tagit yes 2 lines,will give that a try

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i just want to go fishing..........amd ignore all my adult problems



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