Float switch blows up

[just4fun]

I was on my way in when it started to go of and on .And than it whent bang.Good thing I run an out board.

 

[Fish-Hunter]

damned gremlins.

any idea what caused it? it doesn't look cooked from the photos, broken yes but fried no. Was it electrical short blew it up? thats odd, anyone ever have this happen to them b-4??

 

[Little Hawk]

My guess is that the float case leaked and there was no fuse on the switch line. I'm curious: why was it a "...good thing" you were running an outboard?

 

[Justfish]

My guess is that the float case leaked and there was no fuse on the switch line. I'm curious: why was it a "...good thing" you were running an outboard?

Same question here. Only a good thing if you have an open boat and an inside plug. Or open enough to bail perhaps.

 

[Gunsmith]

ONE BIG REASON, no lingering fuel vapors that could have been ignited. Not shouting but emphasizing the issue. Any electrical component in the engine compartment of a gas or diesel engine should be intrinsically safe. Another to not be complacent about is even if you have outboards is if there is propane on board any leak will find it's way into the bilge and wait there for a spark.

 

[Justfish]

ONE BIG REASON, no lingering fuel vapors that could have been ignited. Not shouting but emphasizing the issue. Any electrical component in the engine compartment of a gas or diesel engine should be intrinsically safe. Another to not be complacent about is even if you have outboards is if there is propane on board any leak will find it's way into the bilge and wait there for a spark.

D'OH! Why didn't i think of that!? My apologies for not engaging brain before putting mouth in gear.......

 

[just4fun]

There was no water .The fuse was in the on off button. and my tanks were just above it.

 

[hooktender68]

was there risidual water in or around the switch lately with the cold weather? ,would be my guess to the float falling apart like that.

 

[just4fun]

No water .And it did not fall apart.Look and u can see pieces scatter a round. And it want Bang.

 

[Gunsmith]

For sure it has something to do with arcing current I am surprised it would happen at 12 volts.

 

[Little Hawk]

Does any of the pieces have the words, 'Bin Ladin' on em'?

 

[Sea Ranger]

I would think its from being older plastic and freezing. Now you get to replace it with a new one.....and your good to go.

 

[just4fun]

IT was new .Only afew mouths old .I will not be getting a new one .I ca live with out one.But with one maybe not.

 

[cuttlefish]

From what I can see in the photos, not much sign of overheating on the wires but looks like some sign of arching on the steel ball. The 'on-again-off-again' symptom is also strange if there was no water in the bilge but that might explain the sign of arching on the ball. The ball could have gotten jammed so that you had an intermittent short heating up the air inside enough to expand and cause the explosion without getting the wires hot enough to char. However, a 12 amp fuse should have blown before it got that hot. Puzzling.

Pneumatic switches are an option for replacement. You can mount the switch in a well ventilated location away from the lower realms with only a tube and cup mounted in the bilge. Air pressure builds up in the tube as the water rises and trips the switch. Fully adjustable.
PAR Hydro-Air Model #34875-0000. Comes with 10 feet of plastic tubing which can be cut to length. Had one for years with no regrets. Just make sure the tubing connection is airtight.

 

[Hoochiebob]

Might want to have a look at your bilge pump.An explosion of that magnitude may have been a result of a locked rotor drawing an extremely high current through the switch.
If the switch was indeed stuck on it may have run the motor for an extended time without water- a sure fire way to kill a pump,resulting in my first scenario.