Source of oily bilge?

[drosenfeld]

I have a 1988 Newport 27 in Los Angeles which on occasion accumulates very oily water in the bilge that will rise to just below the float level. There are no substantial leaks visible under the engine and I don't see any signs where water could come in around any thru-holes. We recently replaced the water pump and inspected water system for leaks. I would assume the source of the oil at least would be coming from the engine compartment but I also can't find any drain holes leading from below the engine to the bilge. So I'm wondering if there's something I'm missing here. I realize I need to solve the oil leak, but where's all this water coming from and how is oil getting in the bilge? Could there just be tiny cracks in the engine compartment letting it seep through and the water from above as a result of washing etc?
Also, there is an end to a hose in the bilge area that appears to run through the engine compartment and toward an AC unit that isn't used? Any ideas if this could play a part?
Thanks in advance

[MarkSF]

If it's anything like my Bristol, when motoring the packing gland drips. This water then slops around the area under the engine, getting oily, and then pours into the bilge when the boat is heeled. When you are back in the slip and level, the water has dropped way below the level of the berm under the engine.

The fix was twofold : keep the engine space scrupulously clean, and replace the packing gland material with Tefpak, which hardly leaks at all.

[Ex-Calif]

Originally Posted by drosenfeld

I have a 1988 Newport 27 in Los Angeles which on occasion accumulates very oily water in the bilge that will rise to just below the float level. There are no substantial leaks visible under the engine and I don't see any signs where water could come in around any thru-holes. We recently replaced the water pump and inspected water system for leaks. I would assume the source of the oil at least would be coming from the engine compartment but I also can't find any drain holes leading from below the engine to the bilge. So I'm wondering if there's something I'm missing here. I realize I need to solve the oil leak, but where's all this water coming from and how is oil getting in the bilge? Could there just be tiny cracks in the engine compartment letting it seep through and the water from above as a result of washing etc?
Also, there is an end to a hose in the bilge area that appears to run through the engine compartment and toward an AC unit that isn't used? Any ideas if this could play a part?
Thanks in advance

Welcme aboard drosenfeld.

Chasing water and oil leaks in an old boat can be a lifeling journey...

First - it doesn't take much oil at all to make bilge water look oily. I would set aside the oil issue for a while and focus on water. You should monitor oil consumptoin and see if you can get a measurable consumption over time.

For water -

- The engine is water cooled. All the associated plumbing and so forth for cooling the engine can be suspect.
- The engine shaft runs out the back of the boat. Probably through a packing gland. These can be dry when stopped and drip slightly when running
- Cockpit locker lids - On my boat these are notorious for accumulating water and then spilling over into the bilge
- Any number of stancions, winch nuts, cleat nuts or anything else drilled into and bedded onto the deck.
- Don't forget portlights and hatches...

Good luck...

[drosenfeld]

Thanks so much. This makes sense as I do see corrosion on the shaft and the packing was something I did suspect. Need experienced eye though to see what to replace and will look into Tefpak. Still don't see how the water could pour into the bilge but in theory your explanation makes sense. Thanks again.

[GordMay]

Greetings and welcome aboard the CF, drosenfeld.

[Old Snipe]

Originally Posted by drosenfeld

Thanks so much. This makes sense as I do see corrosion on the shaft and the packing was something I did suspect. Need experienced eye though to see what to replace and will look into Tefpak. Still don't see how the water could pour into the bilge but in theory your explanation makes sense. Thanks again.

Whatever you do...... don't go too crazy tightening the packing. There should be a occasional drip......... depending on the packing system you have. I have seen too many power boat owners score shafts by thinking they should be perfectly dry. Teflon packing if adjusted properly will show a milky buildup at the gland and is normal. It means that there is plenty of water getting to the packing.

I'm not sure of your mechanical background, so I thought I would throw this out there.

[zeehag]

has it been raining?? water is able to enter boat nicely from rain.
place a nice clean engine diaper under the engine to see where the leaks are. it might be from lost angeleses awesome clean bilgewater waters, however that is most unlikely. you prolly have an engine oil leak.
havve you checked the block to see dripping from gaskets?? did you check with a white cloth for stains on engine ?
prolly not yet, eh?

get to it, and discover from where the dripping comes, as oil in bilges is generally from engine, especialy if it is black oily stuff. check level of oil in engine and tranny and proceed from there.
pretend you know a little about car engines and apply that to your boat.
you may want to scrub bilges clean to make sure the oil isnt from previous attempts to add oil to engine and it dripped into bilges or from someone spilling used oil into bilges.
packing is spozed to drip. i have gore tex packing in my ericson and it is dry bilge.
my formosa is a wet bilge boat. i have packing gland dripping, sometimes water pump leaks, and i do get ingress from storms.
but i bet ye a nice cheapo taco dinner in mexico that your engine has a drippiness somewhere. is easy enough to find. use a mirror and a camera to see places you cannot see normally.
btw--also check every single thru hull fitting on your boat for water ingress.
check water tanks for integrity, as wellas all hoses and hose clamps to each and every hose to and from sinks and thru hulls. stem to stern.

ps--welcome

[shorebird]

It may also be possible that its a fuel leak somewhere. It takes very little diesel fuel to create an oily bilge. Any diesel smells in the bilge?

[lancelot9898]

If your mast is keel step that could be the source of rainwater getting into the boat.

[drosenfeld]

Thanks, yes I do see this milky buildup so it might be okay. My goal is to clean the bilge and below the engine, then locate the oil leak and any other water from the engine next time I run it for a while. Then maybe I can sop up that gland leak before it gets to the bilge. The thing that was confusing me was I still can't figure how the water gets to the bilge like there was something pumping or filtering it in there. From heeling is possible. Or maybe just a mystery that remains. Thanks all for the great advice.

[John Drake]

Oil in the bilge could be from transmission fluid or diesel fuel. Both are red in color and easily confused.

To check transmission leaks...just put a white oil adsorbent cloth under the tranny.

Diesel leaks can be tricky to track down. Sources can be:

High Pressure fuel injector pump. Especially if more than 20 years old. You will have to use a flashlight and look for drips while the engine is running.

Could also be that the fuel over flow line from the fuel tank has become loose. Easy to check. One of those things you never think of.

Hope this helps

Best

J

[Charlie]

I had/have the same problem. I replaced my engine. The old one had leaked oil all over hoses and the bilge. I cleaned all the hoses and the bilge. It looked good. I reached up under the floor boards as far as I could and cleaned there as well. Half way into a two month sail there was oil in the bilge. We had been in Gale force winds with waves breaking over the bow. I imagine the water came from that. But the oil. The diaper under the engine was dry. I surmise that it came from under the floorboards and was scoured there from oil of the old engine. The new engine did not loose any oil. I also thought it might have come from some used oil that I had stored but all of those containers were tight. I had to clean the bilge out again it was a PITA. Never answered the question as to the oil but I did find that the keel hull joint was leaking. Fixed that and the bilge rarely fills now. You can use water erase markers or talculm powder to make a line and this may help you to find the direction from where the water is coming. Meaning draw a line and then that place where the line is erased is where the water is coming from.

[Cheechako]

a small amount of oil looks big in the bilge. Don't rule out a tank beginning to leak! can you smell it? is it black or just oily? smell like diesel?

[lifeofreilly57]

The source of water in the bilge?
In an older boat it's anything and everything.
Deck mounted hardware, stanchions, mast if it's keel stepped, ports, hatches, chainplates if they go through the deck, locker covers (if they open to exposed lockers), cockpit drains if the hoses/hardware to them is old, inboard water tanks and fittings, keel to hull joints, hull to deck joints,etc, etc,etc.
Oil? Unless you have an inboard mounted auto pilot with a hydraulic ram the engine and transmission are the only other sources. Just a few drops can make a mess and once it sloshes around your bilge and under the floorboards it can take several seasons to get it all out. It finds all kinds of hiding places when the boat heels.
A packing gland should have some water dripping through it when running under power, it needs it to cool and lubricate the shaft.
On most previous boats I've had I was good for about 3-5 years after re-bedding everything on the deck, including the chainplates and ports. That usually included having to rout out and solid glass the chainplate through deck holes, which are usually a big source of leaks on most earlier production boats.
Stopping leaks is a full time job, I've ended up re-bedding just about everything on my boats on a rotating basis over the years, to me it's just part of spring commissioning duties if you want a dry boat and no deck rot.
My current boat has a 4-108 which are notoriously leaky engines but dependable as all get out, my solution was to put a formed stainless drip pan under it and change oil absorbent mats on a regular basis. I'll address that when I pull it to rebuild it.

The earlier suggestion to use talcum powder to trace leaks is a good one, just use it sparingly, a little goes a long way, I used to do that on auto and motorcycle engines when a hard to trace oil leak popped up.

[Cadence]

I'd find that fast. If it reaches the float switch fines might be your biggest problem.