Heat exchanger on the 2QM20

[Ed Schenck]

So as not to steal Richard's thread I thought I would answer Rardi's question here. Actually I can't answer it because I don't know. I never gave it any thought since most if not all heat exchangers are on the engine at about the same level. Mine is a conversion that was done by a previous owner. It was a pretty crude attachment but I never had a problem. It works because of the big loop in the exhaust hose. The hose goes out the mixing elbow down to the bottom and then loops up to the cockpit sole. Same as today with the new 3YM30. I have never had a waterlift muffler and my 3YM30 does not have the lift elbow.

 

[rardiH36]

Hi Ed:

Thanks for starting the new thread. I had thought of doing the same for my off-topic query, but felt a bit careless this morning ... easier to hit the reply button instead.

Great that you keep pictures of your boat's metamorphoses. Certainly helps visualize things. From the clear view angle of the first photo, the attachment method definitely looks post factory. I had previously thought that the external heat exchanger (to modify from raw water cooling) on my boat was an option from the Hunter factory. Maybe not. Or if the conversion was done by whatever commissioning yard delivered the boat, that also might explain the variation in method.

Changing the hx location on my boat is certainly something to think about. I'll have to take a good look at the clearances around my exhaust manifold area. Or maybe instead of on the engine, I could locate the heat exchanger to a bulkhead inside the engine compartment. But the convenience of the existing location in the lazerette also is nice. Just don't like it right next to the batteries.

Thanks for replying on Thanksgiving Day. Last post from me today. Time to get in the car a trek to the family feast.

rardi

Hi Ed:

Happy T'day.

When looking at your pic of the 2QM20 sitting pretty on the ground, something looked out of balance compared to mine ... -- It's the location of the external heat exchanger that you had mounted against the exhaust manifold attached with what looks like stainless steel hose clamps. Am I seeing right?

This has great interest to me. My heat exchanger is mounted on a bulkhead in the port side lazarette under the seat bench. I have never liked the location because it is right next to the batteries and the solar charge controller and both the sea water and coolant are being routed outside the engine compartment with rather long hoses. One advantage of the locker location however is that the heat exchanger is mounted maybe about 9-12" higher, and comfortably above the water line, than it would be if in the engine compartment which is under the cockpit floor. Also I can check the coolant level (and add if necessary) by the clear access to the pressure cap. Just lift the seat cover (which stays open thanks to those "spring" devices!) and look down. Alternatively, if in the engine compartment I would need to remove the engine access hatch that is on the cockpit floor.

Any thoughts about me mounting my heat exchanger like yours was?

regards,
rardi