Volvo Penta SX-A drive trim problem

[BartW]

when I touch the "trim up" button, the drive trims up, but doesn't stop going up after I've released the trim up button,

switching the engine / the contact "off" and "on" again stops this trimming up.
sometimes during navigation, the drive goes up, without touching the button,

I've opened the buttons in the throttle, and they seem to be clean and OK,
so something else in the trim pump controll system makes wrong contact

(only on Port drive, SB is OK)

anybody has had or knows this problem ?
many thanks for advice !

(we crossed some rough seas yesterday, so water ingress somewhere... ?)

 

[jimmy_the_builder]

(only on Port drive, SB is OK)

Could it be a trim relay problem? Have you tried swapping the up/down trim relays to see if the problem transfers to the opposite direction? Or swap both relays from port to starboard?

Cheers
Jimmy

 

[BartW]

Could it be a trim relay problem? Have you tried swapping the up/down trim relays to see if the problem transfers to the opposite direction? Or swap both relays from port to starboard?

Cheers
Jimmy

but I'm not sure where these realy's are,
I'm afraid they are in the EVC box, and if thats the case, i'm in deep ****
as this box is almost unaccesible on the P engine

trace the electric cables coming from the trim pump, that's the first thing to do,
Boat is in my warehouse on the trailer, so can have a look and do some test

thanks !

 

[jimmy_the_builder]

but I'm not sure where these realy's are,
I'm afraid they are in the EVC box, and if thats the case, i'm in deep ****
as this box is almost unaccesible on the P engine

trace the electric cables coming from the trim pump, that's the first thing to do,
Boat is in my warehouse on the trailer, so can have a look and do some test

thanks !

Hi Bart

This pic seems to suggest that they are with the trim pump (#5 is the relay assembly):

I've had probs with the trim relays on my dph legs; on my, the relay housing had cracked and there was a bit of corrosion. Very easy to change. Note that the way that VP wire the relays up, you need them both to be installed for the leg to trim at all.

Cheers
Jimmy

 

[BartW]

the SX drive is completely different Jimmy,
but thanks nevertheless.

have looked at it today,
and unfortunotly now all is working normal ofcause,

would like to sort out the functioning in case I have the problem again,
and I'm afraid on a SX drive the only parts are:

the switches in the throttle
The EVC box (with software programmed Min/Max trim detection)
The trim pump which is on the OUTSIDE of the transom shield
The wiring

and all these parts have very difficult acces in the Karnic

 

[jimmy_the_builder]

Hi Bart, sorry about the duff info, Marine Parts Europe show that diagram as the exploded diagram for the SX-SLT. I assumed the SX bit made it relevant to you - sorry about that.

Cheers
Jimmy