Intermittent trim gauge issue (KAD300)

[alt]

My starboard engine has recently grown an intermittent issue.

As I cruise along, the LCD gauge goes haywire. It starts reading really random levels. I normally have trim at 0, and it starts shooting up. Sometimes it stays at reading a high reading, other times it jumps back down and up again. Then sometimes it will settle back to it's true position.

NOTE: The leg is NOT trimming by itself, it's just the LCD gauge getting a false reading.

Question is: Where do I even start looking? I have a twin engine configuration so if it's internal stuff I can swap around, I just don't know where to begin.

Sometimes, turning the power off/on again quickly (without killing engine) solves it. Some other times, by pressing the DOWN button, it come back to its true reading.

In 2 years of owning the boat, this is the first issue i've had (apart from a float switch in the shower sump) so I guess i'm not doing too bad

 

[gjgm]

My starboard engine has recently grown an intermittent issue.

As I cruise along, the LCD gauge goes haywire. It starts reading really random levels. I normally have trim at 0, and it starts shooting up. Sometimes it stays at reading a high reading, other times it jumps back down and up again. Then sometimes it will settle back to it's true position.

NOTE: The leg is NOT trimming by itself, it's just the LCD gauge getting a false reading.
If you mean the beach trim VDO gauge, then it is a sensor on the inside of the hull/outdrive (just had one go). Cant recall the part cost but about £200 I think

Question is: Where do I even start looking? I have a twin engine configuration so if it's internal stuff I can swap around, I just don't know where to begin.

Sometimes, turning the power off/on again quickly (without killing engine) solves it. Some other times, by pressing the DOWN button, it come back to its true reading.

In 2 years of owning the boat, this is the first issue i've had (apart from a float switch in the shower sump) so I guess i'm not doing too bad

If you mean the beach trim VDO gauge, then it is a sensor on the inside of the hull/outdrive (just had one go). Cant recall the part cost but about £200 I think

 

[James L]

Before changing the trim sensor, check all your connections.
I had incorrect readings and turned out to be some corrosion on the pins in one of the plugs near the gauges.

Does the reading change while you're stopped?
If it only happens while cruising, sounds like a loose connection to me. Wires moving around as you're going, giving incorrect voltage.
As far as I remember, the sensor is just a potentiometer, and open circuit would be max up, so any bad connection would increase the reading.

 

[alt]

Thanks I'll check connections behind helm later as a first resort

 

[dpb]

Will keep an eye on this thread as I have a similar issue, but only happens over 1500rpm or so. all the lights light up in random order on the gauge and the numbers cycle through a random sequence. Intend to check connections as the pots are only a couple of years old. Could be inside the gauge itself I suppose.

 

[Portofino]

Almost certain inc resistance from corroded spades at the back of the guage .
Does the door open under helm -if so = damp ingress = corroded spades = "Micky mouse " readings

Eg I have been bombing arround SoF with Stb temp guage @ 250 ( yeh right ) --alarm is 93 o C -did not go off ( assume separate century ?)
Magic infra red gun said -top of thermostat 89 ,water pump 30 , heat exchanger 63 , on BOTH engines !!-@3100 rpm
Removed guage -emery papered off minor blackening off spades ,changes female spades -new ones
Hey presto now reads 89 like t,other side -cost nowt to fix

 

[andy59]

Almost certain inc resistance from corroded spades at the back of the guage .
Does the door open under helm -if so = damp ingress = corroded spades = "Micky mouse " readings

Eg I have been bombing arround SoF with Stb temp guage @ 250 ( yeh right ) --alarm is 93 o C -did not go off ( assume separate century ?)
Magic infra red gun said -top of thermostat 89 ,water pump 30 , heat exchanger 63 , on BOTH engines !!-@3100 rpm
Removed guage -emery papered off minor blackening off spades ,changes female spades -new ones
Hey presto now reads 89 like t,other side -cost nowt to fix

Good tip Portofino , I have been trying to sort a high guage reading of 95 degrees although lazer temp says 85 as does the vodia tool on a flat out run .

 

[alt]

UPDATE! PROBLEM SOLVED, thanks to the forum.

I unplugged the connector behind the gauge, redid it and viola! Ran for a few hours yesterday and all is well.

Thank you all... Hopefully this thread will help others in future