Burnt out Engine fuse help

Chrissie

Chrissie

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Tried to go for a sail today, but my engine wouldnt restart, I found the 40 amp main engine fuse for the Beta 14, had melted. The top section that sticks out of the fuse holder, had melted away, and one of the metal posts of the fuse, from inside the holder had melted too.

I popped a new fuse in, but still no signs of life!

A few weeks ago I fitted a new starter battery, and a new Perkins, on off both type switch, and replaced the battery cables.
The starter motor was sticking a bit, having not been started for more than a month, but seemed to be working again after a while of turning it with a spanner.

So any ideas on what could have happened to the fuse?

And apart from changing the fuse holder, and the fuse, are there any other checks I need to make?

Thanking you all in anticipation,
 
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Such a melt down points to quite a serious short. The fuse protects the wiring harness between the engine and control panel. Unless you managed to cause the short accidentally whilst working on the electrics, I'd look for damaged wiring, particularly at the engine end.
The heavier current users from the panel are heaters, starting motor solenoid and the stop solenoid.
If the new fuse doesn't blow straight away, see if it goes when one of these items is powered from the panel'
Good hunting!
 
earlybird said:
Such a melt down points to quite a serious short. The fuse protects the wiring harness between the engine and control panel. Unless you managed to cause the short accidentally whilst working on the electrics, I'd look for damaged wiring, particularly at the engine end.
The heavier current users from the panel are heaters, starting motor solenoid and the stop solenoid.
If the new fuse doesn't blow straight away, see if it goes when one of these items is powered from the panel'
Good hunting!
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More likely that there was a bad connection at the end of the fuse that melted. This would just get hot all the time it was being used until "meltdown"
Suggest you fit a new fuse and holder and take it from there.
Always difficult to give a definitive answer when you cannot see the problem.
 
Of course you must check over all the new wiring before attempting a restart (and the old wiring!). If all looks well, then a new fuse and holder may indeed be all that is required. Components will degrade with age and th fuse and holder have probably suffered with the sticky starter and an old battery... It may be that the new battery finally fed enough current to melt the holder, after all the holder cannot melt if the fuse has blown. I would be a good idea to get that sticky starter serviced, though.

Rob.
 
Chrissie said:
Just popped a volt meter across the fuse holder wires and nothing 0, then tried the starter and still no volts,
Click to expand...
Chrissie
You should be checking from negative battery terminal to Incoming side of fuse, if that's ok move downstream As Alex has alluded to, a poor connection at the fuse will result in over heating, this may be what your looking at, does the fuse wire appear to be tapering towards the center of its span (overload) With a short circuit the fuse element would be melted and mostly not present, without experiencing the two failure modes its hard to appreciate the difference Also its best to use a test lamp rather than a multi-meter. Keep an open mind take your time to evaluate whats going on, a massive short circuit would blow the fuse immediately and mostly likely sparks from the area of the short. A partial short would be show its self taking longer to blow the fuse, and the item causing the problem getting hotter than usual. Hope I'm not overstating the obvious good luck

Michael
 
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