MerCruiser 4.5L 250hp V-6 overheat

[leosmdp]

hello everyone im new here looking to some help from the people who know!!
im having a problem with this motor MerCruiser 4.5L 250hp V-6, the alarm came and put in safe mode...I read a post from 2019 ( https://forums.iboats.com/threads/mercruiser-4-5-overheating.721422/ ) with some example and info but not a proper solve..
1- Is not the impeller in the raw water pump, Clean.
2- I will take out this weekend the manifold and the risers to make a close inspection
if any one had o solve this problem will be more than welcome your info tip and point to check.
Attached 3 pics water system I found a old post here and parts diagram.
Thanks !!!

 

[Bt Doctur]

more likely the poppet va;ve

 

[Scott Danforth]

Did you back flush the cooling system?

 

[leosmdp]

Hi guys
I will check the poppet valve!, I did not made a back flush in the cooling system ( I will find information about it,I dont know how to do).
I bought this Bluetooth scanner to " vessel view mobile " to take a better understanding check temps and read the error code.

 

[Scott Danforth]

Hi guys
I will check the poppet valve!, I did not made a back flush in the cooling system ( I will find information about it,I dont know how to do).
I bought this Bluetooth scanner to " vessel view mobile " to take a better understanding check temps and read the error code.

pull the line from the power steering cooler to the thermostat housing.

connect to hose and backflush.

the tubes in the power steering cooler are smaller than the pickup screen on the drive, so the power steering cooler may be plugged with dead fish, shells, rocks, etc.