Vessel view

[Scott215]

I decided to go with vessel view mobile instead of a new nmea network. I always thought my boat was running a little warm. Turn out gauge is off 10* hotter than vessel view. 156 on the hose at idle. Gauge is telling me 170 to 175

 

[techmitch]

I decided to go with vessel view mobile instead of a new nmea network. I always thought my boat was running a little warm. Turn out gauge is off 10* hotter than vessel view. 156 on the hose at idle. Gauge is telling me 170 to 175

Are you sure the gauge gets it's signal from the same sensor/sender as the vessel view/ECM?

 

[Scott215]

Honestly I don't know, but would you rely on vessel view or gauge. It has a new impeller and 160 t stat

 

[techmitch]

Honestly I don't know, but would you rely on vessel view or gauge. It has a new impeller and 160 t stat

I wouldn't rely on either until I diagnosed exactly why they were reading different.

 

[Scott215]

How do I do that

 

[Scott215]

See if temp sensor wire by thermostat runs to the ecm

 

[Scott215]

And my hours are off by 20 hours

 

[techmitch]

How do I do that

A good start would be to study your boats wiring diagrams and parts manual and also, parts manual/diagram on the mercruiser site bye entering your engine serial #.

 

[ttmott]

Are you sure the gauge gets it's signal from the same sensor/sender as the vessel view/ECM?

They don't. Sensors that interface with an ECM operate on positive 5 volts provided by the ECM. Sensors that drive traditional resistive gauges operate on a negative bias (12 volts).

 

[Jimmy Buoy]

My setup is the same era engines (Merc MPI's). On the thermostat housings are two temp senders. One on the stb side which is a one wire analog type that gets its ground from the cast iron housing that supplies info to the dash gauge. On the port side is a 3 wire temp sensor that provides info directly to the ECM which is showing on your VVM. Three wire sensors have a 5vt reference wire (common to other sensors like H2O pressure senders), a dedicated ground wire (also common to other sensors) and lastly a wire that sends power between .5 and 4.5 volts back to the ECM which depending on the voltage converts it into a digital temp reading.

My one wire sensors also have a higher temp reading on the dash gauge than the ECM info on VVM. I've tested the temp with a laser gun and can tell you that the ECM is correct (in my case).

 

[Scott215]

I would tend to trust vessel view myself

 

[OllieC]

I decided to go with vessel view mobile instead of a new nmea network. I always thought my boat was running a little warm. Turn out gauge is off 10* hotter than vessel view. 156 on the hose at idle. Gauge is telling me 170 to 175

Ditto - gauges a slightly off. Both my oil pressure and temp

 

[Skybolt]

I would use a temp meter and put in the heat exchanger reservoir and monitor it that way so I would know exactly what it is doing. If the vessel view mobile is reading directly from the ECM then I would lean towards that, but there is nothing that says that the ECM sender is good until it proven.

 

[Scott215]

That's true. Had boat out this weekend and never went over 162 the analog gauge said 175

 

[Scott215]

And I really wanted it to see if it was getting hot I do need to do manifolds and risers at the end of this season anyway not from a performance or temp perspective but just the way they look