Mystery water leak

[tartansailboat]

I have a mystery water leak that puts about 1/2 gal of water in my bilge for about 30 mins of engine operation. The history is as follows:

1. Noticed water in the bilge only after engine has been run, noticed increased drip from stuffing box, about 1 drip per 5 sec. OK that is the leak, tightened stuffing box nut to get leak down to recommended one drop per minute. No luck, leak still there

2. While fiddling around with packing nuts noticed stuffing box hose clamps not very tight. Installed 4 new clamps, well tightened, no luck, leak still there.

3. Noticed bad lead from weep hole in water pump, aha, ordered brand new water pump, Moyer model 502 from the ever helpful Ken, now I am in the 21st century regarding water pumps, no leaks, tight as a drum but $265 to the cause, cheap compared to an hour of a real mechanic. But no luck, leak still there.

4. Noticed hose clamps on Moyer SS water lift muffler exhaust not well seated. Had boat yard redo connections with fiberglass 45 deg elbow to get better angle, 4 new super clamps, no leak, aha, I got it. No luck, leak still there.

5. Coincidentally, at this point I noticed that my temperature gauge was not reading. Checked wire for continuity, OK. so the ever helpful Ken, suggested new Isso sender and guage, $85 more to the cause.

5. It must be the anti siphon valve in the water line going to the muffler input. Blew and sucked on that hose, seemed ok but just to make sure put that hose into a bucket, ran the engine, no leak there. But maybe my blowing and sucking on that valve unstuck it so went out for sail. Motored out of mooring about 20 mins, no leak in bilge, aha, success, I got that puppy. No luck, on the way back to the slip, motored about 20 mins and got 1/2 gal water in the bilge.

6. Looked with flashlight while engine was running back to the slip, could not see any leaks in any of the thru hulls nor could I find any water trails although from the position of the water in the bilge, it looks like the leak is coming from the front of the bilge area. Note T30 has engine mounted just aft the mast so that is where all the "stuff" is with the exception of the stuffing box.

I am baffled, any suggestions out there??

[hanleyclifford]

How about the drain holes on the side of the block?

[domenic]

Check keel bolts. if you have a bolt problem, running the engine could shake the keel.
If it is a keel bolt(s), that is something you want to take care of.
I would suggest you dry the bilge. Have someone keep their nose in the bilge, crank the engine, and see if any of the bolts leak.
Also put paper towels around the bottom of the engine. I would check every hole under the water line. All major leaks start as a little leak.

[tartansailboat]

Hanley, where are these drain holes on the side of the block alternator or carb side? Are they visible in the panoramic view of the A4 on Moyer's site? I am aware of two pipe plugs in the block which are removed in order to pressure flush the block, are these the drain holes to which you are referring to? if so, when I last looked at them, they were intact.

[tartansailboat]

I will check the keel bolts but they appear tight. let you know tomorrow when I will run the engine in gear at the dock, against the dock lines.

[jhwelch]

A bit of a long shot, but have you checked the packing nut on the rudder post?

[hanleyclifford]

Have you looked at the connection where the exhaust hose meets the discharge thru hull?

[tartansailboat]

I will check all of those point today, thanks all. I am really concerned about Hanley's suggestion of the drain holes, they appear sound but if they need work, access to the carb side of the engine is limited. will check today.

[ndutton]

You might want to consider the talcum powder technique. Dry the area around the engine thoroughly and dust it with talcum powder. When the leak returns it will leave a clear trail through the dust.

[domenic]

I will check all of those point today, thanks all. I am really concerned about Hanley's suggestion of the drain holes, they appear sound but if they need work, access to the carb side of the engine is limited. will check today.

I had the same problem reaching the carb, and fuel pump. On that side of the engine is a berth. Under the berth is a locker. I cut a big hole in the side of the locker to reach the carb, and pump.
I took some wax paper, wet out two layers of fiberglass mat, stuck the piece I had cut out on the the wet fiberglass. This made a flang on the piece I cut out. after the resin dried I put the piece back in with sheet metal screws. Next time I need to get to that side of the engine, I just unscrew the cut out piece.

[tartansailboat]

very inventive way to get access the carb side of the engine. I just have to remove the batteries and I have OK access.

I checked the drain plugs on the engine, no leaks there thank goodness. Found a small fresh water leak from the water tank, I had just filled it up for an overnight trip to SF and may have overfilled it, but that is definitely not the source of the leak. Ran the engine at normal cruising rpm at the dock against the dock lines, no leak again. Seems to come and go and today it is largely gone. Still a mystery but I will keep checking. Thanks to all for sage advice.

[Al Schober]

How about the side plate behind the alternator & starter? Those bolts are known leakers (replace with studs!) and the plates themselves do corrode out!

Al

[edwardc]

...Ran the engine at normal cruising rpm at the dock against the dock lines, no leak again. Seems to come and go and today it is largely gone. ...

Keep looking. A wise woman once told me "Problems that go away by themselves usually come back by themselves!"

[sastanley]

tartan, Catalina 30's have a notorious leak in the rudder stuffing box when motoring near hull speed, something already mentioned above. If I motor slower (i.e. smaller stern wave) no leak.

If you run the motor at the dock and don't notice it, I'd check a little closer...try putzing around for an hour at idle to see if you still have it.

Modifying the conditions and checking for severity of the leak in those varied conditions may help to whittle down the possibilities.

[tartansailboat]

I think you may be correct about motoring around while observing the bilge.

I did notice a very small leak coming from the vicinity of the water tank. On my Tartan 30 the water tank is underneath the port settee and since the engine is just aft the mast, they are both in the same location. I had just filled the water tank to go on an overnight so the leak from the water tank may have just started. I checked the hose clamps on the input and output of the water tank and could not feel any leak but I cannot see the tank itself.

When we did return from our overnight, there was water in the bilge and it tasted like mostly fresh water (from the water tank?) but with some salt in it, hard to tell. I drained all the water from the tank, about 20 gal, and will leave everything dry out, there was no water in the bilge after I had pumped it out last night. I just wanted to eliminate the water tank as a possible source, although the leak from the water tank was very small, but overnight it could add up.

Similar to your experience, I did run the engine up at the dock in gear for about 1/2 hour and got no water in the bilge, but underway it does seem to fill up. Now that all the engine and floor boards are out, visibility should be OK so I will take the admiral out in the next few days and I will hunt for this leak.

Again, thanks for the suggestions.