Heat Exchanger Westerbeke 10-2 in O'Day 272

[cbourne200]

When I bought this boat in Dec 2011, I was told the 10-2 had recently been overhauled. Although the boating season in Pensacola is very long, if winds are high (15-20), waves are big (modest chop) or temp is not above 60*, wife has a problem with going sailing.

All this to say the boat has has moderate activity for sailing over the last 3 years. Motor is used primarily to get from marina out to bay (approx 1/2 mile) or if winds drop too low. I have not put a lot of hours on the motor. After all, it is a SAIL boat...

Last outing I found temp guage reading close to 200*, so started looking for problem(s) today. Found heat exchanger with some small shell pieces, but also found raw water intake/outlet on exchanger to be partially blocked (approx 1/2 blocked) by salt deposits. Also found hose from raw water pump to heat exchanger to have a hole in it, but that's another story...

What is the best way to remove deposits from heat exchanger? How long (hours of running time) would you expect before the exchanger would be in this condition? I'll attach pictures (started scraping out one port, then decided to bring home and do in comfort of home vs 100* heat in boat!)

 

[Pat]

I've considered cleaning mine but checked it yesterday and it doesn't look clogged, but we
do sail in fresh water vs. salt....I would suggest you reference one of Maine Sails library of 'how to' do things as he has a good one on westerbeke heat exchangers....Good Luck, Patrick in Wichita.....btw....happy Labor Day Weekend!

 

[cbourne200]

I've seen several comments about using Muriatic acid to clean it out, but...

Only areas I see that need cleaning (to me) is the inlet/outlet ports - outside of interior tubes do not seem to be encrusted or anything. With both ports 1/2 clogged, I'm assuming the water flow was not sufficient to keep temp from going to 200*. I thought operating temp was 130-150, but user manual said 170-190 was normal op temp. So not that far off...

Am attemting to use vinegar to keep deposits 'moist' and will attempt to crush/flush out deposits. Other posts suggest inspecting HE every year. I think that is maybe too often, but if PO had cleaned it out at overhaul prior to my purchase, maybe not too often.
I will be babysitting grand daughter for next 3 weeks, so it doesn't look good for getting back to boat before Sept ends. Should have time to get HE clean, too.

Thanks Pat - Have a good holiday and remember me babysitting vs sailing...

Charles

 

[cbourne200]

If anyone's interested, removal of clogged ports on HE has been done. Soaked in vinegar for about 4 hrs, then began cleaning with icepick and a piece of 1/4 x 1 aluminum strap that I had on hand (just in case icepick slipped).

After all material washed out of HE, was able to slide icepick down each tube without force. I assume this means they are clear. Ran multiple gallons of water through HE and through tubes by adding water through different ports.

Then came pencil zinc... Had removed cap when I bought boat, but it was much harder this time. Hope I didn't crack the brazing around the coupling... Will test under pressure (understand there is little pressure on raw water side). As before, zinc was not attached to plug. I cleared opening where zinc should have been (it was same consistency as salt deposits), then started flushing with water. I could hear parts of the zinc ratteling around in the HE. Somehow, with enough shaking and flushing with water, all rattles stopped (assume this means I got all the pieces of the zinc).

Photos attached show bits of salt deposits scraped from ports and pieces of the zinc. Salt deposits were left when I slowly poured out the vinegar I had soaked/flushed the HE.

Now to replace zinc and check for leaking braze...

Charles

 

[Mickstr]

Ice pick? Yikes! I used diluted muriatic acid and lots of water, flushed all kinds of bad stuff out. Water flows great this season..

 

[cbourne200]

Didn't know how hard the salt deposit would be, so started with something with fine point - icepick was best thing I had with a fine point. Thought I might have to chip away at small pieces to get it removed. Turned out not to be as hard as I had thought.

Muriatic acid? Yikes - that stuff will eat a hole in you... Just kidding - I know you are careful with it. I didn't have any 'just sitting around', so went with a more mechanical effort. Still used lots of water too...

If you add up lengths of pencil zinc that I was able to remove, I suspect PO had this 'broken off zinc' problem before. Adding the length of the pieces I was able to get out (some of them went down garbage disposal as I was working in kitchen sink trying to flush with water - couldn't get to those), I have at least 4" of zinc... and the HE is only 2" !