Starting problems

[Stingray]

Can anybody help? Engines start no problem at all while they are cold but after a period of running often all I get when turning the key is the starter motor spinning, sometimes just on one engine but yesterday on both. Only way to start the engines then is using jumps leads from one battery to the other.

Tried changing battery terminals from one to the other to try a process of elimination but it makes no difference. So every time I stop I have no idea what will happen the next time the ignition is turned on. But back on the pontoons the next day they fire up straight away.

 

[hlb]

Is this a petrol engine?

No one can force me to come here-----------
----- I'm a Volunteer!!!

Haydn

 

[Stingray]

No, they are four cylinder 90hp Ford Mermaid diesels.

 

[ccscott49]

If these are the pre-engaged starters, IE with a solenoid on top, they sometimes when a little older, get hot and the solenoid jams, not allowing the pinion to go into engagement with the flywheel, I would take the solenoids off and clean them up, it's a fiddly job, to get them back into engagement, so you may think about taking the starters right off, or getting somebody to do it for you. I have two six cylinder mermaids and my brother two four cylinder. He had this problem.

 

[Stingray]

They are old, about nine years, but only (supposedly) had about a hundred hours use. Not sure whether they have pre-engaged solenoids or not, will have to check. Thanks for the suggestion.

 

[ccscott49]

Easy enough to tell, the pre-engaged, have the solenoids on top of the starters, its not the hours, its the age, corrosion etc. I'm pretty sure thats your problem, the fact that a bit of extra umpff from twinning the batteries, works, points that way. Good luck. Let us know how it works out.

 

[Guest]

Sounds like a short circuit somewhere and the power is lost through the leads, maybe they are not the correct gaugeof cable for starting, the starters could be the older type without the solenoid on top, are they 90hp melodys?, what are they fitted in to, also they could be corroded inside , take them off and clean all the moving bits on the solenoid and pinion, seems strange that more battery power will spin the engines, be carefull not to start a fire !.

paul js.

 

[Stingray]

The engines are apparently pre the melody range, according to Mermaid, fitted into an Aquabell 27. Climbed into the bowels of the ship......well I took the engine cover off really, the starters do not have solenoids. Looking at them there is some evidence of corrosion around the connections so this weekends job will be to clean and grease every one. I like the suggestion of a short circuit or cable size wrong, that's another avenue to explore as I definitely don't want a fire.

 

[ccscott49]

Ah! I thought you had already checked the connections! This type of starter is different, and different techniques are required, if the clean up of connections doesnt work, its staters off and clean inspect.

 

[Stingray]

The continuing story........

Took batteries to a manufacturer who tested and said nothing wrong with them or charging circuit, that was good news but the bad news was that when they were removed we found that the battery box was disintegrating, more work!

Spent last weekend cleaning terminals and tracing wires (when negioating buying the boat the owner couldn't be bothered to turn up so all contact was with the broker whose stock answer to any question was 'I don't know'! Consequently we are still finding out what all the wires are for, more of that later). There are three isolator switches one of which we thought might connect both batteries but no, one is for the electric winch. Thought I would follow the article in June's MBM and clean them but found they are a sealed unit, so swopped them around instead.

So now happy with all connections noted though that the negative wires from each battery appear to be half the size of the positive, not sure if this would cause problems. Cable run from battery to starter motor about six feet and from starter switch to motor about fifteen feet with no solenoid in the circuit (the motor doesn't have one either).

Unable to test last weekend 3/4th as tide too low and the boat never came off the mud. Went for a run this Sunday, about an hour, sat at anchor for about half an hour, went to start the starboard engine and the problem was still there, grrrrrrrrrrh!!!!!!! Jump leads on and it started ok. Next step is to swop starter motors and try and prove whether it is the motor or the wiring.

I mentioned earlier about lack of information from broker, when the weather finally abated in January we motored across the Thames to our mooring in the Roach all at eight knots because the trim tabs didn't appear to work. Later when tracing the wiring I noticed wires going from the joystick to a switch marked 'Spare' flicked this on and hey presto instant trim tabs. There is a lot to be said for having the owner show you round the boat and explain what things are for.

Sorry, seem to have rambled on for ages look out for another update next week when we have swopped the starter motors.