Volvo Gen 8 300hp Overheating

[dogwspts]

Working on a Volvo gen 8 300 hp 2017 closed cooling . Replaced impeller thermostat and motor is still running hot . Not a lot of flow out of out drive ext. less than 200 hours and flushed after every use. I am thing risers any thoughts. Thanks

[DEcosse]

Not really that intimate with that series motor, but here are some general suggestions:
Did you try removing the freeze plugs on the manifolds/risers and flush through those, poking something into the ports to clear any debris?
You could also remove the hose off the sea-water pump and try a manual reverse flush through the intake side to see if there is any debris clogging the take-up side?

[Titaniumboy]

Are the heat exchanger tubes clogged up?

[dogwspts]

Yes tried both heat exchanger clear removed plugs and flushed not coming out on ext side

[stifflkd]

Have you pulled the anode access plates on the exhaust manifolds. If you are thinking risers those anodes should be pretty chewed up.

[dogwspts]

Yes we did and replaced the risers. Operating at 165 to 169 at full RPM. What is the operating temp for these engines Cat converter 5.7 2017 model year.. Thanks

[stifflkd]

That is where I am at on a 2021 350 VP

[sailor55330]

I run 162-165 on the 2016 version. Water temp seems to make the difference.