Coolant system maintenance

[John Langford]

I am going to take off my heat exchanger and have it cleaned and pressure tested. To that end I have read all of the useful advice by Mike V, Ron Hill and others on this topic. However, I still have a question. The submissions mostly focus on the heat exchanger alone. But what about cleaning out the that part of the coolant circulation system internal to the engine block? Does running the engine with a rad cleaner and water before taking off the HX worth the effort or should I just focus on cleaning the heat exchanger itself?

[mark_53]

My thought would be rad cleaner is primarily for cleaning out scale and deposits that restrict the small passageways in a radiator.  The larger passageways within the engine block and hoses are not usually restricted.  If you suspect they are than it probably wouldn't hurt.

[Stu Jackson]

John,


When was the last time you changed your coolant?

[KWKloeber]

John

Understand that "boiling out" the Hx is mainly to clean scale deposited on the sea water side.  You GENERALLY won't get that ocurring on the engine coolant side.

The sea water travels in one direction thru the (relatively) tiny tubes visible when you remove the end cap.  That's where the issues arise when those tubes get scaled up.  The engine coolant travels thru the Hx in the opposite direction between the outer shell and the tubes.

You really have to make sure that any cleaner is compatible with the engine block -- which I would check with your local Kubota dealer, or call Westerbeke.

You'll never have any concern if you are simply power flushing the block, which you can do by connecting a garden hose to a coolant hose, and letting the flow go thru the block with no obstructions.  You want to remove the thermostat, etc.  You can flush the exhaust manifold (which is also a coolant reservoir) separately from the block.

ken

[John Langford]

Thanks everyone for the helpful comments. I should say at the outset that I am not having any overheating issue. The temp gauge is rock solid at 162 degrees. I take my HX end cap off regularly to check for anode debris. The tubes look good and there is no sign off corrosion. The gaskets, caps at both ends and the raw water hoses have been renewed as required. But I have 2200 hours on the engine and the HX has never been tested or cleaned. And, to answer Stu's question I haven't changed the coolant for 6 years. Shame on me!

Perhaps I am taking preventative maintenance too seriously. Do most people get their HX cleaned and tested every 1000 hours as the manual recommends?

[Jim Hardesty]

Do most people get their HX cleaned and tested every 1000 hours as the manual recommends?

Shamrock is in fresh water.  I haven't. 

[KWKloeber]

Do most people get their HX cleaned and tested every 1000 hours as the manual recommends?

nope (tho its a freshwater boat)

[Ron Hill]

Guys : As I posted before, I periodically run some "Lime-A-Way" thru the HXs raw water side.  Seems to help keep the inside clean.

A thought