Author Topic: What fuses should be in a K2 ?  (Read 1236 times)

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2timer

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What fuses should be in a K2 ?
« on: April 01, 2007, 05:31:22 AM »
Hello,
My K2 750 has 3 positions on the fuse block. I have read some talk of 5,7, and 15 amp fuses in their bikes, what models I don't know, but I guess they should probably be the same, at least K2 on. I haven't found this info in either of my manuals.

My bike has 5, 15, and 30A fuses, from top to bottom position, and has blown the 30A. I have a non charging problem I am  about to tackle. I am poring over the posts of Buffo and Golden child particularly, (and many others) and the responses, significantly from Twotired. I have just bought a multimeter and now I am getting some time to work on it again, I will work through those steps and do what I can.

I did notice that before I realised the 30A fuse was blown, the battery was approx. 12.65 V, and approx 11.63 at the terminals with it running. It didn't make a noticeable difference if I revved it up.
After I  a. changed the 30A fuse and
           b. roughly scuffed the fuse holder clips, the charge went from approx 13.4, about idle speed or so,      up to 15.3 at about 3 - 3500 RPM

I don't know if that is a sensible scenario or not, I'll see if I can work out what is going on but I seem to have two problems already,

1. Probably got a fuse twice the amps it should be in it, and it's BLOWN it, and ,
2. if my inept testing is correct, do I now have an OVERcharging problem

So, first things first, should it be 5,7 and 15 or 5, 15 and 30A?

Nev.
« Last Edit: April 01, 2007, 03:41:55 PM by 2timer »

jsaab2748

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Re: What fuses are in a K2
« Reply #1 on: April 01, 2007, 05:49:19 AM »
5, 7, and 15 sound correct. And 15.3  volts charging sounds too high. That in itself may be what's causing the main fuse to melt. Get to the bottom of the charging issue first I'd say, then see if you still have the problem with the main fuse, and possibly another electrical issue. Someone with a lot of electrical knowledge will add to this....

Offline TwoTired

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Re: What fuses should be in a K2 ?
« Reply #2 on: April 01, 2007, 04:04:21 PM »
The Honda Shop Manual schematic shows 7, 15, 5 (headlight, main, tail).  Other bikes have the fuse value cast into the plastic under the fuse. I don't know the exact orientation on your bike.

15.3 V at the battery is a bit high, indicating the vreg isn't doing its job.  Check the voltage at the vreg terminals black to green.  This is what the Vreg uses to determine if the battery is fully charged.   The White wire is the vreg output controlling the strength of the alternator output.  When the black to green goes over 14.5v the white to green should have a lower voltage ~half.  I think the white wire voltage should be even lower, when the Black to green goes over 15V.

Could be the contacts in the vreg have fused.  Or, someone unknowledgeable has tweaked the adjuster, thinking it will improve alternator output. (wrong assumption)

Blown fuses will break midspan the fuselink.  Melted fuses will do so near the endcaps from heat generated by poor fuse clip contacts or poor connections on the back of the fuse block.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
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Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline HondaMan

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Re: What fuses should be in a K2 ?
« Reply #3 on: April 01, 2007, 04:13:24 PM »
Are you sure it's not a K3?
All K2's I've seen have one fuse, 15 amp until March, 1972, then 20 amp.

 ???
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Offline andy750

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Re: What fuses should be in a K2 ?
« Reply #4 on: April 01, 2007, 07:42:40 PM »
Im with Hondaman on this one - K2 wiring harness only has one fuse - connected by 2 red wires. Im guessing since you have a fuse box/holder then its a 73 or later (or someone has changed it) - check and see if you have a reb box below the fuse holder - a saftey starter switch - the K2 didnt have one of these.

cheers
Andy

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