Coolant flushing- Coolant change - Replacing engines zincs

[Joint Custody]

I have a 2000 460 with Cummins 6CTA8.

This boat is new to me in July of this year and has been in fresh water all its life.

Because of the remote location of Lake Powell it is not the most user friendly to have a really good Cummins service tech on hand or close by.

I have a Tech coming " 150 miles away" to the boat to do the 600 hour valve lash adjustment.
Also recommended is the coolant flush and replace.

My question to the members that know whats best is this.

As the boat has been in fresh water all its life do you think "flushing" is still needed to be done or would you just replace the coolant.

The boat is on the hard and getting the bottom done and I dont have water access to run the motors while it is on blocks.

My thought was while the Tech is there do I get the punch list done or should I wait until back in the water and just do the flushing with the coolant change.

Also do you lose and coolant when changing the zincs?

Thank you
you for the advice.

 

[NotHerDecision]

I would just replace it personally. Make sure you order the correct coolant filter without SCA's so you don't have too much additive. In addition, replace the thermostats when you flush the coolant and clean the heat exchangers and aftercoolers. This way you only have to make the mess once. So this is what I would do.

1. Remove the aftercoolers and heat exchangers.
2. Service them both per SBmar.com
3. replace them on the boat.
4. Change the thermostats.
5. Change the coolant filter.
6. replace the coolant hoses
7. refill the boat with coolant, don't forget to dump and replace the coolant on the overflow bottles.
8. you will need to top off the coolant in the spring when you splash it and can run the engines so make a very large note of this somewhere.

9. Drink some Beer... no 2 beers... drink 12 beers and wait for summer.

You do not lose coolant when changing the zincs... they are on the raw water side.

No need to have the tech do it, then you have to do it again when you perform the other maintenance items. I hate changing the impellers on my engines, I would make the tech do that!
Josh