(Only) After sailing, diesel will not start. Take a mechanic sailing?

[Babylon]

3 years is nothing.

My dedicated engine start battery (thick plates for lots of CCA) and domestic bank of two leisure batteries (thinner plates etc) are all a decade old already and still all in tip-top condition.

When on her mooring the wind-generator keeps them topped up, as well as on a sailing passage, so they never ever really get a chance to be hammered.

 

[Graham376]

I think it may be a Mitsubishi S4L, same as our Thornycroft conversion. Could be a solenoid or starter fault when hot. Have you measured battery voltage on both solenoid large terminals when trying to crank with the engine hot? To rule out solenoid fault, I would short the two terminals out with an old spanner or hefty screwdriver.

 

[Topcat47]

If you leave your battery for months without any form of charging and then expect it to start your engine you are very lucky that it does so. Please install a small solar panel and a cheapish charging controller (the controller is a must-have or the panel might overcharge and ruin your battery). About £40- £50 should cover it.

I have a couple of those small panels you get for keeping car batteries topped -up. I got mine from Maplin which isn't a lot of help, but there are others about; try e-bay. They are supposed to be weather proof but I'd not risk it myself. I put them inside the saloon, behind a south facing window. They work.

 

[Spirit (of Glenans)]

I

Thank you all for your suggestions, it looks like cable/connection inspection is in line. A loose connection of some description may be the case.

I may also purchase a new battery - just this morning I got a reading of 14.8 while charging with said engine; something's not right there. I guess the battery is slowly leaving this cruel world.

Isn't 14.8 v normal alternator output?

 

[Boater Sam]

I

Isn't 14.8 v normal alternator output?

Yes, for lead acid non sealed batteries.

 

[Boater Sam]

I do not even want to think about that! The engine (albeit with only 600hrs) was installed some years ago and PO (and myself) did not experience anything like that.

Protection? The exhaust outlet pipe comes all the way up to the deck, after the muffler thingy. No other special arrangements there.

But can you get spray into it which will run back to the engine.? Is there a swan's neck in the exhaust pipe?
An eggcup of water would fill the combustion chambers and cause a lockup.

 

[antaris]

But can you get spray into it which will run back to the engine.? Is there a swan's neck in the exhaust pipe?
An eggcup of water would fill the combustion chambers and cause a lockup.

Yes, yes there is a hefty curve internally in the exhaust pipe - reaches well above the cockpit floor.

 

[antaris]

Yes, for lead acid non sealed batteries.

hm, I thought it was 14.4, no?

 

[antaris]

I think it may be a Mitsubishi S4L, same as our Thornycroft conversion. Could be a solenoid or starter fault when hot. Have you measured battery voltage on both solenoid large terminals when trying to crank with the engine hot? To rule out solenoid fault, I would short the two terminals out with an old spanner or hefty screwdriver.

Yes, indeed, it is a Mitsubishi S4L engine. I have no idea what the solenoid is - so I'll do my homework! Engine always starts cold or warm or hot... in the marina!

 

[Boater Sam]

hm, I thought it was 14.4, no?

14.4v for sealed lead acid and some gel acid batteries.

 

[Topcat47]

I don't know how you're measuring the voltage, but if it's a moving coil meter 3% isn't a huge margin of error. Even if it's a digital voltmeter, 3% isn't a huge margin on the output of an alternator. My DVM reads between 14.3 and 14.9 depending on rpm on my car and it's also got a sealed lead acid battery.

 

[chrishscorp]

Having bought a big battery for the van when it was just not needed it was hidden corrosion on fuse distribution buzzbar which i eventually found, and from the sounds of what you have described I would be looking for a wiring fault loose connection, sounds like the batteries are probably ok

 

[NorthUp]

Yes, yes there is a hefty curve internally in the exhaust pipe - reaches well above the cockpit floor.

Water may be bypassing the waterpump impeller and reaching the exhaust system that way- depends how much heel you have sailing.

 

[Graham376]

Yes, indeed, it is a Mitsubishi S4L engine. I have no idea what the solenoid is - so I'll do my homework! Engine always starts cold or warm or hot... in the marina!

The solenoid is the lump on top of the starter, which has the heavy duty battery cable attached.

 

[RIBW]

...... I would short the two terminals out with an old spanner or hefty screwdriver.

+1 for shorting across the solenoid terminals.
I've only had this happen once (preparing to enter a tricky harbour) but a large mole wrench across the terminals immediately started the engine. A wiring cleanup ensued and all was OK.
Good luck
Bob

 

[richardmmoore75]

You should always have a good jump starter on hand.

 

[Kinsale373]

What about your Battery Isolation switch for the starter battery. How old is it? I had a broblem with one of these a few years ago , I was getting Intermittant connections , similar to what you describe. Once the problem shows up try connecting both cables going onto the Switch together on one terminal. Take the switch out of the circuit. See if it fixes the issue,
kinsale 373

 

[JumbleDuck]

Just a bizarre thought. Are the batteries short of water? Perhaps the heeling reduces contact with the plates, but when upright more energy is produced after a wait?. Certainly starter “clicking” is a sign that the solenoid is not activated, either through a corroded connection or battery weakness.

OP, have you checked the battery levels yet? With your symptoms that would definitely be the first thing I looked at.

 

[sailaboutvic]

Simple answer op try a different batter if you don't want to go to the expensive of buying one on the off chance it's not the battery , use your car battery .
At the very less then you know if it's the battery or the problem is else where

 

[antaris]

I believe that both batteries are closed-type lead-acid, so could not check water level. Testing with a fresher battery will be done, as soon as the lockdown ends (we cannot leave port, currently).

As for the Battery isolation switch, well, my system isolates (opens) the negative bar, so the one switch closes both circuits in one go (I don't really like this setup to be honest...that's another project... or is it? )

Thank you all for your feedback and suggestions, all I need now is to be able to go sailing and do some testing...