Heat Exchanger

emnick

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Is cleaning out the heat exchanger part of normal servicing. no problems with it but I have not had it apart in the 5 years that I have had the boat.
Engine in a yanmar 3jh3e, i huess its time for an anti freeze change also.
 
Yes, I service mine frequently

Is cleaning out the heat exchanger part of normal servicing. no problems with it but I have not had it apart in the 5 years that I have had the boat.
Engine in a yanmar 3jh3e, i huess its time for an anti freeze change also.

It is for me on a Betamarine. I clean it at haulout and again just before launch. But the heat exchangers on the Betas are reputedly not their strongest point. FWIW I usually find enough bits of corroded zinc to make it worthwhile at both ends of the season. I usually change the anode at start of season and just clean up before layup. Usually there is half an anode left at layup and virtually nothing when I change it before launch.

And removing and cleaning the heatexchanger is a pain particularly the rear hemisphere. If I was to request one engineering revison to Beta it would be to change the rear hex bolt for an Allen bolt so I could remove it easily.

Hmmm, I feel a niche after market opening here - a la Speedseal. Anyone have info on the "serviceability" of the other brands of engine vis_a_vis heat exchangers? Some way of increasing the size of the pathetic pencil anode would perhaps also be an improvement ...
 
For most Beta it is an annual service item, for the Volvo MD20xx series they make no recommendation other than changing the coolant every two years (they have no anodes like the Beta). Volspec told me to test the coolant each year and only change it when necessary. I did my heat exchanger (Volvo) for the first time after 10 years and it was spotless - waste of time. Presumably Yanmar will make some recs in their owner's manual
 
For most Beta it is an annual service item, for the Volvo MD20xx series they make no recommendation other than changing the coolant every two years (they have no anodes like the Beta). Volspec told me to test the coolant each year and only change it when necessary. I did my heat exchanger (Volvo) for the first time after 10 years and it was spotless - waste of time. Presumably Yanmar will make some recs in their owner's manual

as was my Nanni @ 7 yrs, no need to change the anode either. It doesnt have one ;)
 
The Service Manual for my 3YM30 says to "clean and check the water passages" at 4 years or 1000 hours. It describes cleaning and inspecting the various parts including the pipe stack.
I did this a couple of years ago with no problem.
Martin
 
I've owned my Beta since 2004, and the heat-exchanger hasn't been cleaned in that time, probably wasn't cleaned for a year or three before then either.
Still works fine.
My panel has a temp. gauge so I would notice fairly small variations.
 
While you are checking the heat exchanger I would recommend checking the bolts on the exhaust bend. Slight thread creep, perhaps, but it's attached to the heat exchanger!
I had a problem with the bolts securing the exhaust bend to the heat exchanger on my previous boat which had a Beta 13.5hp.
I discovered after 6 years of ownership that the exhaust bend was separating itself from the HE allowing exhaust gas to escape. When I tried to take it off to examine the mating surfaces I found that one of the four bolts was turning freely in the hole, i.e. no threads. the other three refused to budge under any circumstances (I injured my eye in the process due to being too close to a slipping spanner in the cramped space!). I had to drill them out and tap for larger bolts. Luckily everything worked perfectly afterwards and there were no problems on the delivery to the new owner.
 
Is cleaning out the heat exchanger part of normal servicing. no problems with it but I have not had it apart in the 5 years that I have had the boat.
Engine in a yanmar 3jh3e, i huess its time for an anti freeze change also.

Yanmar maint. schedule for my 4JH4AE says to clean and check the seawater passages after 4 years or 1,000 hours (if sooner). However, the relevant maint. job on "Cleaning the Seawater Passages" points to "Drain and Fill Closed Cooling System" which is justactually the coolant side and not the sea water side.

I couldn't find any reference to cleaning the sea water side and assume the filter keeps it relatively clear of grot. Corrosion doesn't seem to be an issue. However, I still run the engine on fresh water after lift-out and then let it drain (Inlet valve open, pump impeller removed etc.). I also remove the water injection elbow for a clean up and repaint inside (stainless was pitting but should now last for many years). I do a quick water back flush of the heat exchanger and leave it to dry before spraying inside with WD-40, reassembling and leaving it for winter.

Maint. schedule also says that coolant should be changed every year or every 2 years if using long-life coolant. Local dealer said that this was excessive and suggested changing after 5 years. However, I discovered that Jeanneau use an odd green coloured coolant so I changed this to Yanmar's own (pink coloured) long-life coolant after 4 seasons.
 
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I've owned my Beta since 2004, and the heat-exchanger hasn't been cleaned in that time, probably wasn't cleaned for a year or three before then either.
Still works fine.
My panel has a temp. gauge so I would notice fairly small variations.

I cleaned my 2004 Beta 13.5 heat exchanger every year as recommended by the manufacturer. Each time a number of the tubes were blocked up and had to be cleared with a long thin screwdriver. Its up to you but I would definately clean it out rather than waiting for it to fail.
 
I cleaned the HX on my MD2030 after 13 years and 1750 hours, after a catastrophic impeller failure (under way in the Hamoaze in a F6-7 - don't ask). Apart from a few bits of impeller rubber it was clean. Reassembly involved replacing the rubber boots at both ends - they split as I eased them off.
 
I cleaned my 2004 Beta 13.5 heat exchanger every year as recommended by the manufacturer. Each time a number of the tubes were blocked up and had to be cleared with a long thin screwdriver. Its up to you but I would definately clean it out rather than waiting for it to fail.
likewise_strip it down and clean at least every other yr or annually if i can
blocked tubes-anode residue -and just simply getting the thing to bits is easier the more often you do it-not to mention peace of mind!!!!
 
I clean the heat exchanger stack on the Beta every year. The first time I did it (after 4 years) it was very clogged with tiny filaments of seaweed even though there are two filters on the inlet. Now, doing it every year, it is mostly clear. The anode has now stopped corroding as much as it used to so there's not much debris in the aft cap either.
I've changed the antifreeze once, so far, I think after the recommended 5 years.
 
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