Slow Leak/Hot Bilge Water

[cpat]

I have a 2006 SAN 220 Team - The first two times out this season I have had a slow leak I have noticed. I ran it yesterday and the bilge water at times was pretty hot to touch. The engine temp was cool (touching the exhaust pipes and engine gauge everything was normal). When running the boat I am getting a very warm heat through the vents underneath the driver seat. I fell as if it's something related to the prop shaft and water is coming in through that area as well. I wanted to see if anyone had any diagnosis thoughts on this.

[JayG80]

It’s likely that your fiberglass muffler sprung a leak. Lots of cases where the underside of the muffler gets rubbed against the hull.

**Test everything else that Jeff listed first b/c it's no fun to remove and inspect a muffler.

[NautiqueJeff]

Could be a muffler leak, or a leak anywhere after the exhaust manifolds, or even a leaking block drain plug. Are you sure you put the engine block drain plugs back in after winterization? Could also be a heater core leak if your boat has a heater. Open up the engine compartment with the engine running and you should be able to see if the leak is from the exhaust system. If you don't see anything back there, check under the dash at the heater core.

[bturner]

Hate to ask this but did you winterize the boat last fall and if so how did you go about it?

[cpat]

I will test it this week to see - Would running it with a fake a lake suffice or should I run it in the water? I checked all of the engine drain plugs to see if I could find any dripping but nothing visible. For winterization, I removed both exhaust manifolds, transmission cooler, circulation pump return, hose off bottom of water pump, block drain, v drive drain. Let all of that drain cranked it up for a second to push more out of the v drive.

[SilentSeven]

When you pull the plugs to drain...do you replace them before you store? Reason I ask is that I learned years ago that the drain ports will tend to rust if the plugs are not replaced prior to storage. Had to purchase new exhaust manifolds because of this.

If you did leave them out, I'd carefully check for drips around the plugs.

I'd start by running it on the trailer. That way you should be able to have a dry bilge and be able to see any running or dripping water from the leak. Only downside is if the leak required higher engine rpms to expose itself.

[jmo]

My money is on a cracked heater core given you have “hot air at your feet” (meaning you have an heater) and you didn’t mention blowing out the water lines to go to it in your winterization process. The heater core is the most susceptible component on the boat to incur freeze damage.

if you confirm you have a heater, you can get a small section of hose to create a bypass loop so no water goes to the heater core.