More on the code 25 water pressure switch

Sep 11, 2016
39
Palm Harbor, Florida and Gray, ME
Boat Info
260 2015 Sundancer DA
180 2001 SeaRay BR
Engines
350 Mag w/BR3
3.0 Alfa1
Greetings,
I checked with the technician that does all of my maintenance, and he gave me the Mercruiser water pressure ranges for my engine.(5.7 350 300HP).
Water pressure ranges:
@ Idle 1-3 lbs
@ Mid Range 5 lbs
@ Full Throttle 18-25 lbs
For the most part, I fit the bill...any thoughts??
Cheers,
Larry
 
Welcome to CSR!

Those PSI numbers look good to me. Is there a problem you are chasing?
 
That sensor is a $100 plus dollar pc. of crap, prone to failure. If it's not alarming and reducing power your good to go. Don't get concerned with the numbers, if it's not overheating
 
Welcome to CSR!

Those PSI numbers look good to me. Is there a problem you are chasing?
Hi John,
Yes those numbers looked good to me as well.
The problem arises when the RPM reaches around 3200, and a code 25 appears on the digital speedo. The Raw water pump and the pressure sensor have been replaced with factory parts.
What ye say John??
Cheers,
Larry
 
Don't know about a boat of your age, mine won't do that. Reduces power by 11 % thru the entire rpm range
 
Don't know about a boat of your age, mine won't do that. Reduces power by 11 % thru the entire rpm range
Yes...I suppose every engine is different...Do you think it's possible that the new sensor could be the issue??
I'm wondering if, for some reason it's shorting out around that range.... it's a head scratcher!!!
Thanks for your thoughts,
Larry
 
I agree with your thought that the sensor is a piece of crap... What do you think about the shut down at 3200 RPM? Related??
Seems like that is a circuit code as opposed to a high or low pressure code.
file:///C:/Users/Kathy/Downloads/512au5re9znf.pdf
Try to induce the opposite or different code by unplugging the sensor or jumping the sensor wires.
How many wires does the sensor connector have?
 
Hi Mitch,
Thanks for your response..much appreciated!!
To your question. I believe there are three wires connected to the pig tail..I'll have to check.
I believe your suggesting that I run the boat with the sensor disconnected. Do you think that would cause any major problems??
Your 270 looks great!!
Cheers,
Larry
 
I believe Mitch is suggesting you are getting an erroneous code. By unplugging the sensor you definitely should get another code but I'm not sure how that helps.

That said....code 25 is: Sea Pump Circuit Lo shows up at 90% power and allegedly is a Short in the Water Pressure Circuit. Most of the time replacing the sensor solves it because the sensor does not produce the voltage expected at a given rpm. That said....check the wiring going to the sensor and the connector.

Also.....did your mechanic check for a software update? I seem to recall some sensor calibration issues that they addressed with later releases.

I agree with @scoflaw that the sensor is problematic.
 
Thank you John, and everybody else that has responded to this thread.
The concensus, I think is the sensor is defective. Another $165.00.
Again. Many thanks,
Larry
 
Just spent similar money on OEM and it only lasted 15 hours. Went with a $15 Chinese knockoff, it's not accurate but it keeps my PCM happy with no alarm or power reduction.
 
I’ve had that OEM water pressure sensor be bad when new, out of the box. They are troublesome. I was able to return it as defective.
 
More on the code 25 water pressure switch

Where are up getting this code 25 with a scanner of vessel view?
What audible alarm are you getting from guardian alarm, constant alarm or 2 beeps once per minute.

 
Hi John,
Yes those numbers looked good to me as well.
The problem arises when the RPM reaches around 3200, and a code 25 appears on the digital speedo. The Raw water pump and the pressure sensor have been replaced with factory parts.
What ye say John??
Cheers,
Larry

Sounds like it is a Overheat in port or starboard Exhaust Manifold Coolant Temp (EMCT), 212°F (100°C)
limit
NOT pressuse but flow related. there are two other sensors on exhaust manifold.
use a scanner on the engine it will show much more info.
Capture.JPG
 
Greetings,
I checked with the technician that does all of my maintenance, and he gave me the Mercruiser water pressure ranges for my engine.(5.7 350 300HP).
Water pressure ranges:
@ Idle 1-3 lbs
@ Mid Range 5 lbs
@ Full Throttle 18-25 lbs
For the most part, I fit the bill...any thoughts??
Cheers,
Larry

My scan tool lists my engine's block water pressure norms to be between .5 and 15 psi (assuming .5 at idle).
 
More on the code 25 water pressure switch

Where are up getting this code 25 with a scanner of vessel view?
What audible alarm are you getting from guardian alarm, constant alarm or 2 beeps once per minute.
Good morning,
The digital dash. The tach beeps and flashes two five. Then engine cuts back to around a thousand.
As I recall...the VesselView shows normal pressure and temperature. This only happened at higher RPM. The last time it happened the engine was at thirty-two hundred RPM. It never shows it's ugly head at lower RPMs.
 
Sounds like it is a Overheat in port or starboard Exhaust Manifold Coolant Temp (EMCT), 212°F (100°C)
limit
NOT pressuse but flow related. there are two other sensors on exhaust manifold.
use a scanner on the engine it will show much more info.
View attachment 137412
Sensors in the exhaust manifolds. I'll look into that..
Thank you Tri county
 

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