Engine Flush

[charles]

I just read a "tip of day" on Sailnet that adding a Y-Valve with a hose bib so as to fresh water flush the engine would add years of life to the engine.
I have often though about this and I guess the "Salt Away" product could be used for further protection. And it coulds be a back-up bilge pump.
Has anyone done this to a MK II? IF so where was the Y-Valve installed, between the strainer and engine or between the thru hull and strainer? What was the exact hardware and valve used?
Is there any problems with water pressure from normal city water source -- too much or too little?
thanks
Charlie  hull 1498

[bjmansfield]

Charlie:

Unless I am missing something in the translation, there is no way to fresh water flush your engine using the raw water intake.  You have a closed cooling system, that is the raw water never enters the engine, it is just used to cool the anti-freeze mixture in the heat exchanger then pumped on to the exhaust mixing elbow.  

On engines with open cooling systems where the raw water is actually pumped through the engine and used as the coolant, the flush would be of great benefit in a salt water environment.  Some of the 70's era Catalinas may have open cooling systems  but I am fairly certain that no C34s do.

Jack mansfield
C34 # 1169
High Cotton II
Port Aransas, TX

[Dionysus]

ABSOLUTELY DO NOT do this!  If you hook up a hose to a Y valve at the raw water intake (I have a "T" installed to prime the engine after haul out) the pressure...any pressure will go through the raw water system, through the heat exchanger, into the muffler and FILL THE MUFFLER.  The water will have no place to go and will flow back up the exhaust riser and go INTO the ENGINE!  It will go into an open exaust valve and it's all over!

chp

[Stu Jackson]

Charlie

Chris is right.  There is a basic difference between raw water cooled and fresh water cooled engines.

Raw water cooled engines use the "sea around us" to cool directly, with no heat exchanger.  So, if you're in salt water, the salt water is fed through the engine block.  That's bad news, hence, the idea for using a fresh water flush, kinda like an outboard engine.

Our C34 engines are fresh water cooled, via the heat exchanger.  No nasty salt water gets into the engine itself, so no fresh water flush is ever necessary.

Do, however, check your zinc on the heat exchanger, and replace it regularly.

That's also why this message board beats Sailnet hands down!

[charles]

Chris,
Would water back up into the engine, even if the engine was left running? And assuming I only turn the garden hose on a moderate amount.

I realize this would just flush the salt water from the heat exchnger and raw water impeller plumbing.

thanks
Charlie

[Roc]

To winterize my engine, I unhook the intake hose from the seacock and place it into a 5 gal bucket filled with fresh water.  I let this pump through for a few minutes (adding water to the bucket with a garden hose).  I then put non-tox anti freeze into the bucket and do the same.  I guess if you wanted to flush with fresh water on an on-going basis, you could put a y-valve right after the seacock with a hose attached.  Close the seacock, and open the y-valve and place that hose into a bucket of fresh water.  This will let your engine suck the water out of the bucket.  The drawback on this is you will have a coupling with a valve, some estra clamps, and an open hose right after your intake seacock.  An additional break in the hose and just another place in the system to fail.  Just a thought.

Roc-