2006 Yamaha 225 hpdi water pressure issue

[rob11902]

I developed a water pressure problem over the weekend. My temperature alarm started sounding when the motor was in neutral. Water pressure was at 2. I can't recall specifically what it was before, but I thought it was around 5 or 6 in neutral before. Water stream was there, but was not strong, and did not get hot. In idle gear (either forward or reverse) pressure increased to about 5 or 6 and alarm stopped immediately when the motor was placed in gear. At 4000 rpm, pressure looked to be around 12. I do not remember what pressure it ran before, but the stream was always strong. There is a noticable difference in the strength of the stream. Otherwise, the motor ran fine. Motor has 140 hrs. Bought the boat used a year ago. Don't know if I have the original water pump, but it may be the original. Haven't serviced water pump or t-stats yet. Boat has only been in fresh water and we bump a few stumps at idle through the trees, but nothing hard. It has not been worked in shallow water since I've owned it. Previous owner was a salt water user. Time to replace the water pump? And t-stats? What about the "poppit" valve another post addressed?

 

[rodbolt]

Re: 2006 Yamaha 225 hpdi water pressure issue

in or out of gear at idle should not affect the pump pressure.
are you absolutly positive its an overheat?
did you actually see the overheat visual?
horn tone is the same for all 8 ways to set it.
water detect on that engine wont alarm unless its in N.
in any in-gear position the water detect is silent.

 

[rob11902]

Re: 2006 Yamaha 225 hpdi water pressure issue

I assumed the alarm was due to the lower water flow and lower pressure than I recalled. The stream was not really warm. What else do you think the alarm could be? The alarm stopped immediately when the motor was placed in either forward or reverse.

 

[rodbolt]

Re: 2006 Yamaha 225 hpdi water pressure issue

I told you what it was.
its water in the fuel detect.
check the filter cup on the engine.
if its not full of water then unplug the detect harness and retest.
the detect switch sometimes gives false alarms. alarm ONLY sounds in N and NEVER when in any in gear position.
you could always read your owners manual .
why they did the water detect this way I have no idea, the anganeers rarely consult me.

 

[rob11902]

Re: 2006 Yamaha 225 hpdi water pressure issue

Thanks for the education Rodbolt. I don't have a manual. Since the problem only happened over the weekend, I have not been able to get one yet. You, however, are a living manual. I've seen several of your posts. Your knowledge of motors is amazing. I will check the filter cup, test the water detect and check back in sometime later.