VP DP-E Trim indicators gone wild.

A_8

A_8

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I've got 2, one for each leg and they have both, at what seems to be ruffly the same time started living a life of their own.

First thing I noticed was that they suddenly showed about 5 degrees less then they should.

Second thing was if I trim down as much as possible and then leave it, both indicators start counting up at about 1 degree a second. To stop this I have to trim in again and then quickly trim up a few degrees.

I am not sure where to start looking for the problem, from what I can tell there is the sensor on the legs, the instruments and the connections in between. I've disconnected and reconnected the instruments without any change.

It must me significant that both behave the same way and I think I must be missing something very simple but I just cant figure it out.

Anyone recognize this or have any ideas I could try?

Thanks/Michael
 
Sounds like you have air in the hydraulics. Very odd that both have the same symptoms. Are the oil levels ok?
The other possibility is the the rack and pinion system. Sometimes, the pinion gear breaks one of its plastic spokes that can leave it a bit springy. Again, odd / unlucky that both are the same.

Eddie
 
If you trim the legs out to say plus 2 from minus 5 and are on the plane, if the legs go to minus 5 again the chances are the rams are leaking oil past the inner seals, or the valves in the trim pumps are pitted and leaking oil past them back to the fluid tank, you can trim the legs right out to plus say 5 or 6 depending on how thay have been set, you will feel the ride angle of the boat then as the bow will be high up, if the bow dips in, and the gauges move towards the minus figure all on its own then you have a leak past problem and the boat will have to come out of the water to reseal the rams, you could try the pumps first by clamping off the flexible hoses to stop oil passing by back to the trim pump, but you will have to do this when the legs are set at a plus figure, if they still go to minus then its the rams that are leaking oil past the seals.
 
Thanks both but I realize I was not clear in my original post.

It is only the indicators that are acting up, the trim function works fine. It seems they have reset themselves indicating -5 when the actual legs are at 0. This has happened mid season while in the water, they were fine in April and now not.

When I trim down to max they (the indicators) indicate -9 for a second and then start to climb until 34 but the legs stay where they are.

I just spoke to the guys who run Marine Parts Europe and was told that the indicators are off their range at -9 which might explain the indicators counting up to 34 on their own.

This then leaves only one symptom which is the 5 degrees off on the indicators. I guess the only explanation would then be Pendana's suggestion about the broken plastic spokes.

This happening on both legs at the same time seems very unlikely, perhaps I should have gone to the casino instead of taking the boat out for a run :)

I did not know these could break under normal circumstances, maybe the plastic have become less flexible and more fragile over the years and now barnacles or clams break it as I move the legs up and down.

Have you seen this before?

/Michael
 
Can you confirm that these symptoms are happening whilst tied up and not under way. It is very puzzling. Clutching at straws perhaps, you could try trimming the drives right in and adjusting the reading from -9 that you say you get, to -4 using the little potentiometer on the back of the instrument and see if that has any effect.:confused:


Eddie
 
It's happening whilst tied up and yes, that was my original plan to adjust the potentiometer however I wanted to understand why it had happened in the first place to make sure it would actually fix the problem.

The more I think about it, the broken spokes is the only credible cause for this to happen. The other commonality between the legs are the age of the plastic, a lot of barnacles and clams this year and that I have not been trimming the legs fully up during the last couple of months, I did two weeks ago so that could explain it happening to both legs at the same time!

I think this is a good example of getting some help and now this post is searchable and potentially of value to others.

/Michael
 
me too

Michael
as a 'newbie' I wholly agree the value of these fora.
I have had a similar, but not identical, problem on my boat (Sealine F33) which I thought that I was imagining as it only started this weekend. The port leg seems to go all by itself from 5 to 0 over about ten minutes but that seems to be it.
I have to confess that I have not got the 'feel' yet (or the weather) to see what material difference it is making to the attitude of the boat (sorry, I have a PPL and 'attitude' is the word I use, maybe I will be told the correct term for a boat - 'trim'?)
 
A_8 said:
a lot of barnacles and clams this year and that I have not been trimming the legs fully up during the last couple of months, I did two weeks ago so that could explain it happening to both legs at the same time!

I/Michael
Click to expand...

When you leave the boat, you don't leave the legs raised do you? This can leave the rams exposed for the little critters to attach to such that the next time you trim in - pop go all the seals!
 
Pendana said:
When you leave the boat, you don't leave the legs raised do you? This can leave the rams exposed for the little critters to attach to such that the next time you trim in - pop go all the seals!
Click to expand...

No I don't and for the same reason you state.

However with this incident in mind I will trim them fully up and then down again every now and then to make sure nothing grows to solid to the pinion gear and potentially breaks the spokes.
 
AllanJ said:
Michael
as a 'newbie' I wholly agree the value of these fora.
I have had a similar, but not identical, problem on my boat (Sealine F33) which I thought that I was imagining as it only started this weekend. The port leg seems to go all by itself from 5 to 0 over about ten minutes but that seems to be it.
I have to confess that I have not got the 'feel' yet (or the weather) to see what material difference it is making to the attitude of the boat (sorry, I have a PPL and 'attitude' is the word I use, maybe I will be told the correct term for a boat - 'trim'?)
Click to expand...

Your problem might be more related to the original response I got, quoting volvopaul;

"If you trim the legs out to say plus 2 from minus 5 and are on the plane, if the legs go to minus 5 again the chances are the rams are leaking oil past the inner seals, or the valves in the trim pumps are pitted and leaking oil past them back to the fluid tank, you can trim the legs right out to plus say 5 or 6 depending on how thay have been set, you will feel the ride angle of the boat then as the bow will be high up, if the bow dips in, and the gauges move towards the minus figure all on its own then you have a leak past problem and the boat will have to come out of the water to reseal the rams, you could try the pumps first by clamping off the flexible hoses to stop oil passing by back to the trim pump, but you will have to do this when the legs are set at a plus figure, if they still go to minus then its the rams that are leaking oil past the seals."

Even if you are not yet familiar with the trim of your boat you should be able to see and feel the difference if you are in still waters. If its only one leg then the boat will tilt and try to turn as well.
/Michael
 
Just wanted to confirm the root cause of my problem and add some value to anyone who might get the same problem.
The fouling have been bad this year and this caused a spoke on each leg trim sensor to break when I tilted them fully up late in the season hence the 5 degrees off.
 
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