Difficult getting up on plane (2855, 7.4, B3)-gctid385126

[Guest]

A couple weekend ago we had some friends out on the boat with us. With 8 people on board (nobody down in the cabin) the boat would not plane off. At max throttle it would plow through the water with the nose up. With 3 or 4 people it will plane off after about 50 yards and then i can pull the the the throttle back and stay on plane. Im not convinced my trim tabs are working, but i dont think it would have made much difference.

What am I doing wrong? Whats the procedure for using the engine trim when taking off?

I have been trimming the drive all the way down and then giving the boat throttle until it comes up on plane, then trimming the drive up to pick the boat up. Am i doing this wrong? Ive never operated such a heavy boat.

[Guest]

RMSLLC wrote:
A couple weekend ago we had some friends out on the boat with us. With 8 people on board (nobody down in the cabin) the boat would not plane off. At max throttle it would plow through the water with the nose up. With 3 or 4 people it will plane off after about 50 yards and then i can pull the the the throttle back and stay on plane. Im not convinced my trim tabs are working, but i dont think it would have made much difference.

What am I doing wrong? Whats the procedure for using the engine trim when taking off?

I have been trimming the drive all the way down and then giving the boat throttle until it comes up on plane, then trimming the drive up to pick the boat up. Am i doing this wrong? Ive never operated such a heavy boat.

8 is a lot of people for a 28' boat but I would think the 7.4L should be able to still get that boat on plane. I have had 6 in our 2859 with the 5.7L and was able to get up on plane no problems (with full tabs down though).

I would check your trim tab operation at the dock. You should be able to see them no problem as someone else operates the switch. Or run them to what should be the full down position and then go look at them.

Your procedure sounds fine. I start with tabs fully up, engine trimmed in, advance the throttle and when I get some speed built up then I will operate the trim tabs to their full down position and trim the motor out and back off the throttle once fully on plane.

[706jim]

Don't be afraid to ask three or four people to go into the cabin for the minute or so required to get up on plane. It makes all the difference in the world. Once planing, they can return to the back cockpit.

[Guest]

706jim wrote:
Don't be afraid to ask three or four people to go into the cabin for the minute or so required to get up on plane. It makes all the difference in the world. Once planing, they can return to the back cockpit.

Yes, that would definitely help, forgot to mention that.

And make sure that you have enough approved flotation devices for that many people.

[Guest]

The ideal process for planing is:

Trim drive in

Tabs all the way down

Throttle forward smoothly to full throttle

As it comes over the hump, pull tabs up, trim to running position

As others said, that's a lot of people, so send a few forward. Even just one can make a huge difference. On my previous boat once you got to six people in back with a full fluid load, it wouldn't plane. Just sending the admiral to the v-berth, who is only 112 pounds, would quickly send it over the hump and plane out.

[Guest]

All the above conversation really relates to being over-propped for the load. Your engine just can't spin the prop fast enough with the heavy load to get you up on plane. With your normal load, you need to note what your maximum rpm is. Compare that to your motor specs for your boat. You should be very near the specs. If not, you need to do prop adjustments to get it to spec. Personally, I like a prop that will take me just a little over the max rpm. That means that when I have extra load, I will still have the power to get me up on plane. Talk to your prop shop and explain what your problem is, what the specs of your boat are, and how you want the boat to perform. If you trailer, consider having two props, one for load, like weight or skiing, and another to speed. Then you can change based on what you are doing for the day. Another advantage is now you have an extra prop to carry, in the event something happens to the one you are running.

Ken

Pugetsoundog (woof)

[Guest]

Pugetsoundog wrote:
All the above conversation really relates to being over-propped for the load. Your engine just can't spin the prop fast enough with the heavy load to get you up on plane. With your normal load, you need to note what your maximum rpm is. Compare that to your motor specs for your boat. You should be very near the specs. If not, you need to do prop adjustments to get it to spec. Personally, I like a prop that will take me just a little over the max rpm. That means that when I have extra load, I will still have the power to get me up on plane. Talk to your prop shop and explain what your problem is, what the specs of your boat are, and how you want the boat to perform. If you trailer, consider having two props, one for load, like weight or skiing, and another to speed. Then you can change based on what you are doing for the day. Another advantage is now you have an extra prop to carry, in the event something happens to the one you are running.

Ken

Pugetsoundog (woof)

This is great advice if the OP is going to have 8 people on board on a regular basis. If this is just a once in awhile thing sending a few people into the cabin is a much simple solution.

[Guest]

Thanks for the advice guys. I have discovered part of my problem is my trim tabs are not working. When I push the switches nothing happens. Where do I begin troubleshooting this? None of the breakers are thrown under the console. Thats as far as I have gotten.

I dont have a trailer. The boat is in the water year round. I dont regularly have many people on the boat. In addition to 8 people, we also had a full water tank, a full tank of fuel, and about 4 full ice chests, plus everything else we keep stored on the boat. Im convinced it was just too much weight at the back of the boat for it to plane. We were out for a night cruise, so I wasnt too concerned with going fast. I just wanted to see if the boat would do it. We settled for hull speed and everyone was happy.

[msd58]

RMSLLC wrote:
Thanks for the advice guys. I have discovered part of my problem is my trim tabs are not working. When I push the switches nothing happens. Where do I begin troubleshooting this? None of the breakers are thrown under the console. Thats as far as I have gotten.

I dont have a trailer. The boat is in the water year round. I dont regularly have many people on the boat. In addition to 8 people, we also had a full water tank, a full tank of fuel, and about 4 full ice chests, plus everything else we keep stored on the boat. Im convinced it was just too much weight at the back of the boat for it to plane. We were out for a night cruise, so I wasnt too concerned with going fast. I just wanted to see if the boat would do it. We settled for hull speed and everyone was happy.

Check pump connections and solenoids (if equipped) in engine compartment. There are two pumps one is for your engine trim/tilt the other is for your trim tabs should be marked Bennett on there somewhere.

http://"http://www.bennetttrimtabs.c...ers_manual.pdf

http://"http://www.bennetttrimtabs.c...leshooting.pdf

[Tabman]

RMSLLC wrote:
Thanks for the advice guys. I have discovered part of my problem is my trim tabs are not working. When I push the switches nothing happens. Where do I begin troubleshooting this? None of the breakers are thrown under the console. Thats as far as I have gotten.

I dont have a trailer. The boat is in the water year round. I dont regularly have many people on the boat. In addition to 8 people, we also had a full water tank, a full tank of fuel, and about 4 full ice chests, plus everything else we keep stored on the boat. Im convinced it was just too much weight at the back of the boat for it to plane. We were out for a night cruise, so I wasnt too concerned with going fast. I just wanted to see if the boat would do it. We settled for hull speed and everyone was happy.

You most likely have Bennett Trim Tabs on your boat.

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://"http://www.bennetttrimtabs.c...yer.php?vID=10

This video covers "No Noise From The Pump" http://"http://www.bennetttrimtabs.c...yer.php?vID=13

Below you will find troubleshooting you can print and take to the boat. Step 3 is a good place to start.

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).

[Guest]

Wow. Excellent info guys!! That will be a big help. My money says they are disconnected. I just replaced both batteries and I dont remember seeing any extra leads (+ or -). I need to locate the pump and trace the ground wire first. Im betting someone disconnected it to swap batteries and forgot to put it back.

[dmcb]

SwampNut wrote:
The ideal process for planing is:

Trim drive in

Tabs all the way down

Throttle forward smoothly to full throttle

As it comes over the hump, pull tabs up, trim to running position

As others said, that's a lot of people, so send a few forward. Even just one can make a huge difference. On my previous boat once you got to six people in back with a full fluid load, it wouldn't plane. Just sending the admiral to the v-berth, who is only 112 pounds, would quickly send it over the hump and plane out.

You could have just shifted the beer Carlos.

[Guest]

Carlos listed the best procedure. I have had some luck getting up on plane quicker with heavy loads by what I call 'walking the chines' - in other words turning the wheel a bit from side to side while going for plane and shifting the attitude of the boat from the port chine to the starboard chine etc and sort of 'walking' up to plane. Seems to work for me.

[Guest]

SwampNut wrote:
The ideal process for planing is:

Trim drive in

Tabs all the way down

Throttle forward smoothly to full throttle

As it comes over the hump, pull tabs up, trim to running position

As others said, that's a lot of people, so send a few forward. Even just one can make a huge difference. On my previous boat once you got to six people in back with a full fluid load, it wouldn't plane. Just sending the admiral to the v-berth, who is only 112 pounds, would quickly send it over the hump and plane out.

This is great advice, it basically what I do to get on plane. 8 people and that much stuff is a big load and a lot to ask of the slightly underpowered(IMO) 2855 but it can be done. You need tabs! Also be sure your bottom is clean! I also have my 2855 in the water full time and as soon as I feel it really struggling to get on plane, I pull it(fortunately I have access to a trailer) and pressure wash the bottom and that drastically improves performance.

[Guest]

Got the tabs working. Wow what a difference!! The boat jumps up on plane twice as quickly compared to without. Those are a must-have!