Coolant in bilge

[Akapeterc]

When my motor is sitting still For several days I lose coolant from my Reservoir and then several days later it appears in my bilge it can’t be coming out of the reservoir because all the pipes lead to a separate bilge below the engine is there some way possible it could be going out through the hot water system which is heated through the motor. I never seem to lose any coolant well the motor is running it always seems to be while the motor is still on I am using in Marcoola which is red in colour and it’s the only place on the boat where this could be coming from

[zeehag]

fill cap fail. replace cap. get correct cap. take old one with ye when you go to napa auto parts.
best thing is to check every hose also for leakage. goodluck., mine was fill cap. thankfully it is an easy fix.

[Akapeterc]

Can’t be filler cap as that would leak into the bilge under the motor which is not connected to the main bilge

[Attikos]

Looks as if you've answered your own question in saying it can only come from the water heater. Loose or cracked heater hose? Cracked or corroded coil inside the heater box? Leaky purge valve? Whatever it is, it's in the coolant system, not the hot water system. Shouldn't be too hard to find it.

[sailorboy1]

put some paper towels under the hoses and see if they get wet

[Kenomac]

Your water heater coil has corroded and has a few pin holes, so whenever your hot water heater heats up, it forces water into your engine coolant system. You need a new hot water heater. Your freshwater pressure system is also probably cycling for no apparent reason.

We were plagued with the same issue for two seasons. Good luck.

[Akapeterc]

Does the red coolant get circulated into the hot water system ?

[Akapeterc]

I don’t understand how water getting forced into the engine cooling system would get coolant in the bilge

[belizesailor]

Originally Posted by Akapeterc

Does the red coolant get circulated into the hot water system ?

Typically the coolant is circulated thru a heat exchanger in the hot water heater. One side of the HE has coolant circulating & the other fresh water to be heated. So a leak in the HE could get coolant into the house fresh water. A leak in the hoses between engine and water heater could cause coolant loss there too, but normally the water heater and associated coolant plumbing would also be in the enigne room...are they on your boat?


Which make/model water heater?


And...are you certain the red stuff in bilge is coolant?

[Kenomac]

Originally Posted by Akapeterc

Does the red coolant get circulated into the hot water system ?

The coolant won’t pass into the hotwater system unless the problem becomes extreme, so don’t worry about that. The freshwater travels through to the engine coolant system via small pin holes in the hotwater heater coil under pressure, mixes with the coolant then is expelled via the coolant system reservoir cap, then drains into the bilge through the overflow line. When your waterheater is turned on, you should be able to see it begin to drip from the engine overflow after the water heater reaches maximum temperature.

It’s a strange mystery because it will appear to you that your engine coolant is always topped off.... so it becomes a puzzle trying to solve the coolant in the bilge dilemma.

[Akapeterc]

My hot water heater is not near the engine but across the other side of dining area. It could be the hoses that run to it. I will have a search along the hoses for a leak. The coolant reservoir cap over flow hose goes into the bilge below the engine not the main bilge were the coolant is going so it can’t be coming out of the cap. Does the coolant travel in the hoses to the hot water system or is the fresh water recirculated? If the coolant travels to the hot water system a hole in the hoses could be it. If I run the generator and turn on the hot water heater could the slight pressure that builds up when it is hot cause the hoses to leak if there is a pin hole in it?

[sailorboy1]

No because you ae looking for a coolant leak, not a potable water leak

[belizesailor]

Originally Posted by Akapeterc

My hot water heater is not near the engine but across the other side of dining area. It could be the hoses that run to it. I will have a search along the hoses for a leak. The coolant reservoir cap over flow hose goes into the bilge below the engine not the main bilge were the coolant is going so it can’t be coming out of the cap. Does the coolant travel in the hoses to the hot water system or is the fresh water recirculated? If the coolant travels to the hot water system a hole in the hoses could be it. If I run the generator and turn on the hot water heater could the slight pressure that builds up when it is hot cause the hoses to leak if there is a pin hole in it?

Thats unusual to be that far away...

The hoses connect to the engine right? And it heats water when you run the engine?

[Akapeterc]

Yes the engine heats the water while it’s running