Bleeding Air from Fresh water cooling

[coolchange]

My boat came with a "red dot;;Heatercraft" heater that runs off of the Fresh Water Cooling part of my engine. The problem was that the heater was in the forward berth, which I am never in while the engine is running....so I moved it up to the port stowage area at the helm

OK...the heater is now "above the radiator cap" ( a term the manufacturer uses to say you will need to do something) and it needs to be bleed but I am at a bit of a loss as to how to get that done without making a mess. The manufacturer advises a "bleeder valve" but makes no effort to share how, or where. I have pretty easy access to both lines (don't know which is supply and which is return)...would the bleeding take place at the heater or down in the bilge..below the radiator cap? Is there a special valve or ?? Is this location going to cause the "fluid" to run out the radiator cap every time I open it? If yes...got any suggestions to keep that from happening? Should I install a valve in one of the lines to use later?

FYI: there are 5/8th hoses in and out of the engine...these go to a pair of "T" fittings and each tee feeds/returns at the engine (Isuzu 157). One set to the moved heater, the other set goes to the water heater. The Tee lies port side bilge below the engine...easy to reach. I don't think the water heater is in play due to it being -below- the radiator cap-( I moved this from the fwd cabin because will never need heat down there while underway but to like to have warmth at the helm...I did this on 2855 with no problem so am being caught a little off guard.)

Thanks for any suggestions.

[DougSea]

I can think of a few ways to approach this. Since the air is going to seek the high point you'll want a bleed valve up near the heater. You could put in a T and something like this: http://www.ebay.com/itm/JEGS-Performanc ... 4897.l4275

Fill the system, close the radiator cap, open the valve and start the engine. Air should come bubbling out. Close the valve, shut her down and check levels. Repeat until no more air exits the valve.

While I'm thinking about this, have you tried the heater manufacturers website? This would be an issue on any boat with the heater mounted up high in the boat.

[Mariner]

The bleeder valve should be at the highest point in the system. Theoretically, it would only bleed out air, but that's absurd in practice. In reality, it will spew a fluid/air mixture for a while, and then, once it is only spitting water, you will close it. To avoid a mess, install a T fitting in-line at the highest point in the system, and then a valve (pointing up) on the third leg of the T. Then, off the valve, run a short length of hose into a bucket or, even better, a gallon jug.

[coolchange]

Thanks for the response...it will help as I can't complete this untill we launch for the Rendevous...I don't have a way to run the engine while in the pasture.

Also, too bad you can't make the trip this year...lots of nights on the water are good!