Engine Coolant Loop Leaking at Water Heater

YYZRC

I've now eliminated all sources of water in the bilge except the water heater. I am tired of the small leak at the fittings where the "coolant" water from the engine circulates through the water heater. I've tried double clamping with new clamps and cutting the hoses shorter, to no avail.

Any suggestions?

aero3113

Could it be the barbs that are leaking and not the hoses? I never had an issue there except when a barb corroded….

LaRea

You're seeing raw water in the bilge, or engine coolant?  The loop from the engine should be coolant.  

PickleRick

If it's coolant you can remove the hose, clean/dry well and apply rubber cement to the barbs. Reinstall and let it dry a few hours before refilling/using.

YYZRC

@LaRea boat is raw water cooled. I can tell it’s the loop that’s leaking as there is staining on the water heater at the barb. 

@aero3113 what size is the hose, 1/2” ID? I am going to buy a coupler for now. Might try some Permatex sealant or similar but if that doesn’t work I may just eliminate the loop.

EDIT: discovered that fresh water is leaking out around the fitting where the coolant loop barb exits the tank.

aero3113

I think it’s 1/2 ID. I have a coupler at the boat I can measure but probably won’t be able to till later today.

Pat310

Bypassed mine due to leak at water heater. 5/8” hose

kordo

I disconnected mine.  I found the water too hot after running the engines for a couple hours and when away from the dock I turn on the water heater when charging my batteries to put a larger load on my genny.  When at the dock, no issue since I am connected to shore power.  

YYZRC

@kordo I was thinking along the same lines. I have an inverter/lithium setup so I only run the genny at night to cool the cabin for sleeping. 

After discussing with the admiral, we figure the loop is of minimal value to us as we never shower upon arrival at our anchorage. I ordered the appropriate plugs to eliminate the loop; 22-428611 (circ pump plug) and 22-37372 (intake manifold plug).

YYZRC

@Pat310 @kordo did you do anything on the water heater side, or did you just leave the connections open? Wondering if it would be smart to put a loop on the water heater that is filled with antifreeze or better to just leave it open?

TonyG13

YYZRC said:

@kordo I was thinking along the same lines. I have an inverter/lithium setup so I only run the genny at night to cool the cabin for sleeping. 

After discussing with the admiral, we figure the loop is of minimal value to us as we never shower upon arrival at our anchorage. I ordered the appropriate plugs to eliminate the loop; 22-428611 (circ pump plug) and 22-37372 (intake manifold plug).

@YYZRC Thinking about doing the same. Where did you get your parts from?

YYZRC

They were like $10 each so I just ordered from my marina parts dept.

Grahamu

YYZRC said:

@Pat310 @kordo did you do anything on the water heater side, or did you just leave the connections open? Wondering if it would be smart to put a loop on the water heater that is filled with antifreeze or better to just leave it open?

If you leave it open make sure it is drained.

aero3113

If you decide to fix it, keep the coupler on the boat in case the heater coil fails. It’s one of my emergency items….

YYZRC

There is probably close to 2 pounds of hose between the engine and the water tank, not to mention the weight of the water in the hose. I bet the weight savings will increase fuel economy!! Just doing my part for the environment. 

Pat310

YYZRC said:

@Pat310 @kordo did you do anything on the water heater side, or did you just leave the connections open? Wondering if it would be smart to put a loop on the water heater that is filled with antifreeze or better to just leave it open?

I checked to make sure the water drained by connecting one end of the disconnected loop to the shop vac. 

YYZRC

Well, this is frustrating. The leak is actually between the tank fitting and the coolant loop barb (circled in pic below). Will try some JB Weld but I think this one will require welding or complete replacement.