primary circuit calorifier leak

[blue-max]

Looks like I have a leak from the primary circuit -engine looses freshwayer coolant and water in the engine bilge. Wonder if any common faults with this installation and where to look. Some horrible iron pipe fittings I would like to change and maybe now I think of it there is AOL so electrical problem as AC breaker tripped - I solved that problem by disconnecting the faulty circuit from the breaker but never identified it.
Perhaps its time to replace the calorifier completely - what is the original make? Like for like best way to avoid extra installation hassles? Advice appreciated. Ocean 47 2000

[Craig]

I'm not sure if I understand your problem completely but I can advise that a common problem with QL calorifiers is that the heat exchanger in them that heats the water using the engine coolant rusts through or cracks.

This happened to me about 18 months after we took delivery of our boat. When the boat's water pump is turned on, fresh water from the tank goes through the hole in the heat-exchanger and pressurises the engine coolant. The coolant then overflows from the plastic header tank into the engine bilge. It doesn't matter whether the engine is on or not. If you have your fresh water pump turned on, engine coolant will come out into your bilge.

We were in Turkey at the time and could not get a QL replacement. We got a "Quick" brand that has worked well since. ( touch wood). Check the dimensions before you change your calorifier.  The Quick 18 litre tank has the same external dimensions as the 20 litre QL make.

If you get a new system, I would recommend that you consider the size of the electrical element used for heating the water from mains power if you have a generator on board. We changed our 1200w element for a 500w element. We have a 1kv generator that we use to charge the batteries ( about 480w maximum) and heat the water. ( 500w). The generator charges the batteries and heats the water at the same time. You would need a much larger generator if you have a 1200 w element and need 480 w to charge batteries. On shore power, we never get cold water, even if 4 people shower one after the other.

Craig
"Shirley Valentine"
Gold Coast
AUSTRALIA

[geoff]

I am not sure of your engine but I would suspect the fresh water circulation pump . Over time these tend to leak and can be pricey to replace, if the leak is slight try Bars leaks from a car parts place. Geoff

[blue-max]

Thanks for the replies. Is it right to assume the new ql tank continues the old flaws of the past. Was the quick tank straight forward fit or did pipewok/fittings need to changed. The water in the primery circuit seems to be leaking even when not used - gravity?. The secondary circuit holds it'd pressure well - water flowed from tap 9 months after pump last used. When I try to feel the cylinder there is water on my hand. Don't think this is condensation. The engine fresh water pump shows no sign of leakage. Cylinder is likely to fail sometime soon -it is 16 years old so may as well do this before I find I can,t use the engine. But I want a good one!

[tiger79]

Looks like I have a leak from the primary circuit -engine looses freshwayer coolant and water in the engine bilge.

The secondary circuit holds it'd pressure well - water flowed from tap 9 months after pump last used.

If the water in the calorifier is holding its pressure, I can't see how you can have a leak in the calorifier coil.

[MarkTheBike]

Looks like I have a leak from the primary circuit -engine looses freshwayer coolant and water in the engine bilge.

On the assumption that you have a normal freshwater/antifreeze coolant (i.e. vivid green), is the water in the bilge green or clear? I was losing coolant from the engine and had water in the bilge but they were not related - I had the dreaded hole in the heat exchanger (coolant disappearing into the exhaust) and a coincidental leak in the cold water system (near the calorifier) into the bilge under the engine. Water on the hand could be condensation if you're in cold damp weather, e.g. UK.

[Craig]

If the water leaking is green and if your fresh water system is holding its pressure ( pump not coming on without fresh water being used in boat) then the problem is not a rusted through heat exchanger. It is likely to be a connection in the hoses from your engine to the calorifier.

A rusted through heat exchanger in the calorifier will force fresh water into your engines fresh water coolant system and out the plastic filler tank if the boat's fresh water system is pressurised. If you have been running the engine and have the fresh water pump off with a tap open, there is a risk that your green engine coolant will be forced into your boat's fresh water system.

The Quick and QL heaters are interchangeable, but beware of the overall dimensions. On our Bav 38 ( 2009) we had to fit a slightly smaller calorifier when we changed from QL to Quick. The fittings appear to be the same and as the connections to the tank are either rubber hoses from the engine or plastic fresh water pipes any variation in their location on the calorifier is not an issue.

Craig
"Shirley Valentine"
Gold Coast
AUSTRALIA

[blue-max]

I follow the thread. Engine fresh water has been topped up in the past with tap water! So no colourant. No danger of freezing here in southern turkey but not good for protection against corrosion. So will now fill with anti freeze and see if I can trace leakage. I would like to check heat exchanger - is there a simple way to do this? Boat is on the land

[Nigel]

I follow the thread. Engine fresh water has been topped up in the past with tap water! So no colourant...

I suggest using Fluorescein to trace the leak, it's what it is for.

Then flush and refill with locally bought coolant; this will have appropriate temperature and corrosion protection.

[MarkTheBike]

I agree with Nigel but that requires the engine to be running. To avoid that, see if you can beg, borrow or steal a radiator pressure tester. It's a pump and gauge that fits over the filler cap for the coolant and, when pumped, will pressurise the system. If it decompresses slowly then it's probably a leaky joint somewhere. If quickly then it's possibly a corrosion hole in the H/E (not too difficult to dismantle and examine). Oh yes, definitely use a coolant mix. Stops all the crap building up in the water.

[Impavidus]

Blue max.
If I am reading the thread right you are running the engine on fresh water in the primary cooing system with no anti freeze? Your engine needs antifreeze even if your in the tropics. The mixture lubricates the water pump bearings and seals. It also has an anti corrosion element to stop the inside of your engine and the clorifier corroding.

I would suggest a couple of things.

First put antifreeze in, the green Volvo antifreeze will flourless in torch light.
Drain the water in the hot/cold system and run the engine see if the coolant level falls in the engine. If you do not have pressure testing equipment and' If it does disconnect the hoses from the clorifier and join the two ends. You will need drain the coolant in to a clean bucket for re~use.  Top up the coolent run again.
If you are still losing coolant it's the engine leaking. If the coolant level goes up and coolant comes out the header tube or header cap, then your engines heat exchanger is blocked and the raw water is forcing its way past the O rings or rubber caps. (Depending what engine you have.
1.   If the level is constant then the clorifier heat exchange coil is perforated and when the Hot/cold water system is on it is pressurising the engine coolant through the hole in coil.

If you have a pressure gauge, fittings and foot pump you can check the clorifier coil for drop off pressure and a hole in the coil.

Hope this is of use

Best regards.

Ant.

[blue-max]

Many thanks for the advice, you have given some ideas how to test the system. If I get to a conclusion I will post the result