riser question

[c-stick]

I have a 27' searay with a mercruiser i/o 5.7<br />I've owned the boat through 1 season now and recently was told that I should drain the riser using the petcock under them after every outing.<br />I've never done this before and just wanted a second opinion .<br />The boat is mostly used in salt water<br />thanks

 

[dmorley]

Re: riser question

If you have a fully closed cooling system the only salt water in your system will be the riser and heat exhanger. My own pretty much self drains when pulled out of the water. I doubt if yours does when left in the water. At any rate if you drain the water that leaves air+salt=rust. If you don't drain that leaves Ho2+salt=rust. Some say leaving the water in is best others say differently. The best of course would be to flush with fresh water.