Patina in fresh water heat exchanger?

[Whidbey]

I suspect this is normal, but wanted to check with the salts on here. Got a VP 5.7 280C with a stock heat exchanger. I flush in a horse trough and flush again before I go out...on my own well. I notice after a week or so the water turns green, is this usual? Wouldn't know it if I didn't run the motor before going out or on muffs or in a green garbage can

 

[jerryjerry05]

Re: Patina in fresh water heat exchanger?

If your running it in a horse trough, The exhaust and maybe the water you introduce from the lake/ocean will turn it.
You running it in salt or fresh?

 

[Whidbey]

Re: Patina in fresh water heat exchanger?

Thanks for the reply, J
I run in salt (green water) exclusively. I flush after each trip and then flush again before, just to do a system check....put a lot of money and time in her and I want to check things out good before I go into the strait. So, I don't see how it could be from sea water as it gets flushed out, but was thinking maybe manifold rust or like I say patina. Just wondering if anyone had ever noticed such a thing or do I need to watch for a failing exchanger or electrolysis....or don't worry about it.
Thanks, Duane

 

[jerryjerry05]

Re: Patina in fresh water heat exchanger?

If you have a heat exchanger do a pressure test.
Any radiator tester should work?
Another thing??
You have an oil cooler in the system?
Sometimes they can leak?