Bravo III water flow sensor; where is it?

[tphinney]

So I had a wonderfull day on the water last Saturday. then I washup the boat and flush it just to notice that my smartcraft water flow is showing 0.0 flow to 0.1 :smt013. temp is not rising and I am showing water exiting the exhaust so I ran for about 10 minutes with no over heating in anyway. average temp was about 168 degrees.

So my assumption is that the smartcraft water flow sensor is off or bad. Anyone know where this is so that I can check it/replace it. :huh:

for FYI the Raw water impeller was replaced in the spring.

 

[Henry Boyd]

I can tell you it is NOT on the B III. The only stock sensor there is the trim.

You might use the link in the manuals sticky and download your engine manual. My 496 manual maps out all of the sensors

Henry

 

[tginz]

Were you flushing the engine with ears or an inline hose link? I know with my 5.0 B3 when I flush the engine with a garden hose I get a zero to .1 reading. A real high pressure hose I can get .2. Drop it in the water and I run 5-12 psi depending on the rpm. I panicked the first time I flushed with hose that the motor was running dry given the low or no smartcraft reading. The exhaust outlet water and no heat up means you're pumping just fine.

You were not clear on how you were flushing.....so I took a guess.

tginz

 

[Dave S]

I have been searching thru some of the engine manual information I have and can't find it but it has to be somewhere on the output side of your Sea Water pump before it gets to the circulating pump. I would think it would be fairly easy to find but that's just a guess. Since the sensor is probably bad you may want to visit your local dealer and buy a new sensor and at the same time ask them where it's located.

Sorry I can't be of more help.

Dave

 

[tginz]

Just been cruising my SELOC manual. Can't find it either. Sorry

 

[tphinney]

I'm pretty sure the sensor is bad cause normally I get from .8 to 1.2 PSI at idle on the muffs and a bit more on throtle up. but this scared the @#$* out of me when I first noticed it.

 

[freddie]

i'm experiencing similar problem with my 2008 260 sundeck;on my boat the sensor is located way behind the engine-you have to look really far back past the back of the engine about centrally located-it is connected to an electrical wire and the sensor screws in like a spark plug into cooling system-i've replaced two already and the dealer says that's just the way they are. i've never been able to find it in the manual-mechanic showed me.

 

[keokie]

On 496's Mercruiser put them in what are very poor excuses for raw water pumps.

 

[papogator24]

If you're talking about the water pressure sensor, it is on the transom side of the engine. I will go take a picture and report back in 20 minutes.

 

[papogator24]

Here you go.
Side View

Front View facing transom

 

[240da]

On ours the water pressure sensor is on the power steering cooliing tube directly aft of the engine and by the steering linkage. Ours is a pressure sensor not a flow sensor.

As far as pressure, in the water (not on hose) we get about 1.5psi @ idle and about 18psi @3500RPM.

 

[Morpheus]

I had mine replaced 4 times in 2 days how's that for failure. According to the Service Manager Mecruiser has some new sensors he's trying to get a hold of to fix this problem. You will have the same issue with the PITOT sensor. Mecruiser initially thought it was a static charge build up so they had my tech add more grounding but that didn't help.

 

[frankjr66]

Hello All I am begining to wonder if im having the same thing, I was out in the S.F. bay last saturday came home late due to fog flushed first thing in the morning and had flashing AL on the smart water psi dial and showing 1.0 or 0.2 psi but seem to run normal temp so i turned it off ??