All of a sudden - A Bilge Smell, and Battery Issue

labatt · #1 (**permalink**) 10-07-2008

So last night our bilge started smelling. We've been in fresh water for the last couple of years and it's been fine. Last night, at Liberty Landing Marina in salt water it started to stink - badly. There is no more water in it than before. In addition, when we left this morning, our engine battery was dead. This has never happened before either. I'm wondering if there's an electrolysis issue that is stimulating a reaction in the bilge and caused our battery to drain? Thoughts?

FarCry · #2 (**permalink**) 10-07-2008

Could you describe the smell? What I am getting at is...that if something burned up on your boat that could cause both of your problems. For example if your bilge pump float switch is stuck in the "on" position the pump could have gotten hot and drained your battery. Same with a fresh water pump.

Maybe there is a crack in your battery case and acid is eating up your boat and putting off bad fumes. I would start with the electrical issue, solve it and it may resolve your odor, I mean your bilge odor, not your odor.

labatt · #3 (**permalink**) 10-07-2008

Batteries look good - no corrosion, and they are in dedicated boxes - no leaks there. We just figured out how the salt water is entering our bilge though... apparently two bolts came off of our stuffing box and it was, well, dripping far more than it should be. It then drains into the bilge. With all of the motoring we've done through the canals, down the Hudson, etc (Over 70 engine hours in the past week), they must have been loose to start and then vibrated off. That could have been REALLY bad! We still don't know what's up with the batteries... we haven't been off engine power or shore power for long enough in the past few days to run them down. The bilge smell is just nasty - not a burn smell, but a bacteria garbage pungent smell. The bilge pump still works too, float switch to be checked shortly.

hellosailor · #4 (**permalink**) 10-07-2008

Maybe the garbage smell is just from the leak allowing in greater than usual quantities of river water and shore-side water? You can get come nasty smells from the mud-dwelling bacteria that are exposed at low tide, and they must be more prevalent in the water you'd be taking in while at the marina--in shoal water.

Mysterious battery loss, probably more important. Check the alternator diodes (i.e. reverse current flowing in the charging lead when the engine is shut.) Could be all that motoring took out a diode, and now the alternator is acting as a ground short when the engine is not running.

labatt · #5 (**permalink**) 10-07-2008

Silly question... how does one go about checking the alternator diodes?

sailboy21 · #6 (**permalink**) 10-07-2008

Quote:

Originally Posted by labatt

Silly question... how does one go about checking the alternator diodes?

Buy "Boat Owners Mechanical and Electrical Manual" by Nigel Calder

labatt · #7 (**permalink**) 10-08-2008

I'll order it tomorrow and it will take a few days to get. In the meantime, since we're having this problem today, can you describe the process to check them?

floatsome · #8 (**permalink**) 10-08-2008

Puzzling that both problems occurred together. Could be a coincidence, but I can't thank of a common cause. About your battery issue:

Consider whether anything was turned on during the night that could have drained the engine battery.

If it was on shore power overnight, check the shore power charger.

Check all the connections at both ends of all the battery cables. Clean and tight? Wires in good condition?

A bad battery will not accept a charge, even if the alternator is fine.

Easiest way to check an alternator is remove it and take it to a shop. Most communities have a shop that can check alternators. Some things to consider in meantime: Measure the battery voltages with engine off all sources of charge and switches off for about an hour. Then with engine running, what is the alternator output voltage? That's a start: shouldn't be too high (say > 14.6?), and should be greater than the battery's voltage early in the charge cycle, and then not too low when the battery is charged up. The exact numbers depend on how the voltage regulator is set. Basic alternators have a fixed maximum voltage, while those running through a smart multistage regulator might float at a lower voltage after initial charging, say just over 13.

About the odour: consider head plumbing leak, or freezer compartment drain into bilge.

xort · #9 (**permalink**) 10-08-2008

Salt water in the bilge could get very smelly. We brought our boat from salt to fresh and some of the smells from salt permeated head hoses has disapeared.

labatt · #10 (**permalink**) 10-08-2008

Engine started OK this morning... batteries were fine. I'm going to keep an eye on them, but hope that whatever it was won't happen again. I would consider shore power, except we had AC equipment on and it didn't register any issues. We worked our butt off last night to clean the bilge - between bleach, bilge cleaner, toilet brushes, scrubbers and hauling off buckets of disgusting bilge water so we didn't pump overboard, we probably have the cleanest bilge for the day (until we get more water tomorrow). As I mentioned, the source of our water intrusion is our stuffing box, and it's dripping at a rate of one drip every three seconds underway. The bolts are pretty tight, so I'm thinking it may be time to repack.