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Blackshear
1st April 2012, 12:13
Read the sticky, or more or less got to point 3 and started skimming.
So firstly: The last thing I've done to my bike electrically other than a new motobatt battery 6 months ago is replace the spark plug leads and carbon grease the plug caps and the wire-thingies-to-the-spark-leads-box (Step-up transformer?) last week. The old leads read Suzuki 1990. I figured I'd start with an easy gremlin being the mysterious 1st cylinder getting no power when it rains. So far, so good. Even feels like it pulls stronger around the 13-16k region.

But then there's the hard one.

Intermittently, maybe once a month or once a week, my GSF250 sits with the ignition on but nobody is home and a punch around the battery/fusebox seemed to help (Half of the time) sort things out.
But then I noticed that my dash and headlights seemed far dimmer than when I first installed the battery 6 months ago, they're almost blank in the sun. If my memory wasn't to be trusted, it's confirmed that upon starting the bike there's suddenly double the dash juice, so I figured an investigation would fix it. I started checking all of my leads for possible cuts or corrosion, most connections were quite clean or otherwise clean enough to dismiss until I came across the fuse box. Look at this bad boy.
261032

Obviously, it was quite warm to the touch.
So, I ask this: Why is it very hot and what will fix this? I'm going to take a stab in the dark and assume there could be a short somewhere in that box, which would explain the drowsy current in the morning so maybe condensation (and rain) would have something to do with it. I couldn't see or smell anything, nor any liquids other than the CRC I blasted in there yesterday.


TL;DR
My 25A fuse that has my balls in a vice is getting extremely hot
It is intermittent - but obviously an issue at all times
Occurs predominantly overnight, however I was stranded for 5 minutes at the supermarket this morning, which is new.

Apologies for the length, hopefully it's not a horrible waffle to information ratio.

spanner spinner
1st April 2012, 14:17
by pass the fuse holder with a new one, the contacts in your old fuse holder are stuffed to put it plainly. The fuse contact points are forming a restive point and this causes them to turn into a heater toasting the fuse and making the problem worse. The restance is also what is causes the lights to be dim when they are running off the battery, when the engine starts the reg/rec cuts in to run the lights so they then get brighter. your battery is also charged through this fuse when the bike is running which will burn the fuse holder further. I have seen problems like this cause nice little fires which are great fun when they start under the seat, for some reason sods law kicks in when you need to get the seat off in a hurry to put the fire out and the key allways jams in the lock.

Blackshear
1st April 2012, 14:23
by pass the fuse holder with a new one, the contacts in your old fuse holder are stuffed to put it plainly. The fuse contact points are forming a restive point and this causes them to turn into a heater toasting the fuse and making the problem worse. The restance is also what is causes the lights to be dim when they are running off the battery, when the engine starts the reg/rec cuts in to run the lights so they then get brighter. your battery is also charged through this fuse when the bike is running which will burn the fuse holder further. I have seen problems like this cause nice little fires which are great fun when they start under the seat, for some reason sods law kicks in when you need to get the seat off in a hurry to put the fire out and the key allways jams in the lock.

Pretty keen on not toasting my balls, to be honest.
Alright, I'll start looking for a new fuse box. Are they generic? There's a 2x2 plug and a 2x3 plug in the bottom of the box to accommodate for.

Cheers for the reply.

mossy1200
1st April 2012, 16:32
Pretty keen on not toasting my balls, to be honest.
Alright, I'll start looking for a new fuse box. Are they generic? There's a 2x2 plug and a 2x3 plug in the bottom of the box to accommodate for.

Cheers for the reply.


go to repco or super cheap and get a 25amp inline fuse and just remove the wiring that goes to that fuse holder.

http://www.supercheapauto.co.nz/online-store/products/SCA-Automotive-Fuse-Holder-In-Line-Blade-Standard.aspx?pid=120454&menuFrom=7104#Description

link.That one holds up to 30amp standard fuses like the ones in your bike

Blackshear
10th April 2012, 19:50
go to repco or super cheap and get a 25amp inline fuse and just remove the wiring that goes to that fuse holder.

http://www.supercheapauto.co.nz/online-store/products/SCA-Automotive-Fuse-Holder-In-Line-Blade-Standard.aspx?pid=120454&menuFrom=7104#Description

link.That one holds up to 30amp standard fuses like the ones in your bike

Cheers for that mate, went and bought one today.



Cheers for the replies, I shy far away from messing with wires, resistances and the like.
Too delicate.

Latte
10th April 2012, 20:10
I just resolved a similar issue with my car. Indicators would randomly blow, and the fuse would look like it h% melted . Turned out to be the wire for the trailer hitch was touching the exhaust, when the exhaust got hot enough to melt the wire it would short out, when it cooled down it would be just enough for the fuse to not blow, but the indicatrs would be very dim, and the wiring and fuse would get really hot.

So if tthe other option above doesm't resolve take a look for a partial short or bad earth as well.

jellywrestler
10th April 2012, 20:37
what's actually on on the bike when the fuse is hot?