88 VN750 Keeps blowing main 30 amp fuse?????

[Steel Draconian]

As i'm pretty Fik at electrics (Avn't got a clue) can anyone tell me wat i should be looking for / at to sort this problem out? Nowt happens when i leave ignition on/ with or without engine running. nor when Lights on/Off. Only happens when running for 5 to 10 mile? (20 Fuses between Drybrook 'n' Leeds & 7hrs) Put a new Battery on it b4 setting off, wud it be owt to do with that? Any help appreciated and info on this bike..Ta. (we all got to learn sometime) :confused:

[guydewdney]

sounds like a wire is chafed / split and is shorting to the frame.

the most common place for this is round the headstock - try leaving the ign on and turning the steering - does it blow the fuse?

also check (as happened on a mates ducati) that there isnt a wire chafing the seat - when he sat on his bike it was ok - until he hit a pothole - it blew the fuse as the extra weight pushed the seat onto the wire.

[Sir Ewok]

I'm with Guy on this, got to be a short circuit to keep blowing main fuse. Another prob could be water collecting at bottom of ignition switch or in connectors somewhere in loom, especially if left standing outside for a long time without running.
Did you need to put the new battery on 'cos the old one was fecked? If so could have been a continual drain on battery from chaffed/wet/damaged wiring. Also check wiring is correct to manual, DIY wiring work or adding extra lights etc could be causing problems if not wired correctly.

[WALLACE]

Defo a short in wiring,try main links to rear lights, especially brake wires as will only pop when brakes bn used ,prop chaffed at frame or brake switch.

[Steel Draconian]

Checked Loom to Lights, Battery, fuse Box, etc. Only Broken wire I found was the Neg lead to frame(Fixed and re-placed) Problem is I've just bought the bike from the daughter of a biker thats taken the Devine Road in the sky(R.I.P). Don't no the History and feeling my way through varying mods. (Hard wired lights,wen there shunt be none,etc) I know the Bike was stood outside for a yr & hasnt been used since Rock & blues 2003(Except for an odd 223mile's). Main fuse seem's to be live even when no key's init?? should that be the case? I know i must be missing something sum-wer? To the lads that have offered advice...A very much appreciated Thankyou! :D

[Dougie]

Main fuse should be live as feed goes from battery thro' fuse to ignition switch then to rest of the loom.Have you checked the fuse holder itself?Any corrosion there could cause problems.

[Steel Draconian]

Main fuse should be live as feed goes from battery thro' fuse to ignition switch then to rest of the loom.Have you checked the fuse holder itself?Any corrosion there could cause problems.

Thanks Dougie! No problems with fuse holder itself, checked all plugs n leads that lead to it. going to retrace steps so far, must be missing something? Its a pain in the arse, i've only put 11 mile on it since i got it!

[Dougie]

You could have a wire broken inside the insulation.Check for any signs of wires having been trapped in the past.I had to do a total rewire on my GS550 because of stuff like that. :eek: Hopefully it won't come to that for yourself.

[Mad Dog]

It may be the voltage Regulator/rectifier.

A fellow club guy had the 1500 vulcan and kept blowing fuses, he even blew 2 batteries up because of run away charging.
The second time it also took the CDi which cost £470 to replace. Whereas the reg rec was £45.

After replacing the above, all was well.

[Steel Draconian]

It may be the voltage Regulator/rectifier.

A fellow club guy had the 1500 vulcan and kept blowing fuses, he even blew 2 batteries up because of run away charging.
The second time it also took the CDi which cost £470 to replace. Whereas the reg rec was £45.

After replacing the above, all was well.
Gunna replace the reg rec as you mentioned, cant harm anyway (Dont fancy the £470 bit) & already started to strip wire insulation to check? Thankyou Lads for your help & when i've finally got the prob sorted I'll let you know the outcome! Any further suggestions are welcome & if I'm looky i'll see you at a rallie soon.

[Sir Ewok]

My trike doesn't have any fuses and when I had probs with the wiring it kept blowing bulbs etc. A m8 of mine went through all the wiring, taking out bell wire and shoite prvious owners had put in, but every time you turned the bars onto full left lock, I lost side lights, indicators and rear brake lights on one side. Checked all wiring and connections visually, remaking any that looked iffy. Finally got the multi-meter out and found a broken wire inside the insulation + a connection that looked good, but was totally dead. Going to have to wire in fuse box and solenoids (have none of those either) to bring wiring up to scratch.

[weedavieaxe]

:D a tip i got was when you'r looking for wiring faults take the fuse out and fit a bulb in-line instead. if there is a short the bulb will light(without anything switched on cos then the bulb will light anyway) and you can"wiggle test" without going through tons of fuses.I dont think a broken wire would cause the fuse to blow without shorting so if the insulation is fine i'd leave it and keep looking for a short.

[Choprocker]

My thinking was the reg/rec too.
Why did ya put anuvver battery in? did it just need a new 1?
You can test the reg/recs if ya got a manual tells you how in there, most of time, lol.

[Steel Draconian]

My thinking was the reg/rec too.
Why did ya put anuvver battery in? did it just need a new 1?
You can test the reg/recs if ya got a manual tells you how in there, most of time, lol.

Bike stood for a yr, Battery knackered! No I avn't got a manual (Wish i had)

what does the Reg/rec look like? (elecreically thick)

[Steel Draconian]

:confused: Problem stands as it is now: No Keys in & Fuse; Slight buzzing noise from fuse box?
One set of wires from fuse box run underneath to a square metal thingy? (What is it?) The wires that run to this box from fuse box get Hot.
Metal thingy started to smoke when i last put fuse in, so pulled plug straight away. (not knackered cos bike still starts)
Problem seams to be from battery to fuse box?
I would also like to say to all of you, THANKYOU! :D & thanx for baring with me, but i did say i was electrically thick! Now if i was spraying,cutting or welding, that would be a different matter! :cool:

[greg]

may sound a bit odd but is the battery the correct ampage for the bike?
the little black metal thing could be a regulater i have a big reg/rec on my bike and a smaller one as well about 1"square .
got to be over current for the thing to start smokeing or wired the wrong way round i e shorting the box thing out.
good luck

[Steel Draconian]

may sound a bit odd but is the battery the correct ampage for the bike?
the little black metal thing could be a regulater i have a big reg/rec on my bike and a smaller one as well about 1"square .
got to be over current for the thing to start smokeing or wired the wrong way round i e shorting the box thing out.
good luck

Cheers greg for advice will check on it??

[Mad Dog]

Very hard to say,

reg/rec is usually a finned unit down near the swinging arm on the left side.

smallbox under seat likey to be Sarter Solenoid Relay.

If you were closer to the South I could have a look.

I'll see if I can find a manual, but it is a bit like teaching a blind person to Tango.

[Steel Draconian]

Very hard to say,

reg/rec is usually a finned unit down near the swinging arm on the left side.

smallbox under seat likey to be Sarter Solenoid Relay.

If you were closer to the South I could have a look.

I'll see if I can find a manual, but it is a bit like teaching a blind person to Tango.

Thanx mad dog. The box i'm on a bowt is metal, bout 2" x 2" n finned! du ya recon thats the reg/rec?
:confused:

[Spike]

Have ya tried ebay for a manual ?

[Mad Dog]

Thanx mad dog. The box i'm on a bowt is metal, bout 2" x 2" n finned! du ya recon thats the reg/rec?
:confused:

Possibly

I only have a VN1500 book for an older model, somewhere out in the workshop................

[Dougie]

If all else fails take it to a sparkie.Might cost a bit but it'd be cheaper than new reg/rec,ignition etc....

[Steel Draconian]

Have ya tried ebay for a manual ?

Nope? but it werth a try!

[Steel Draconian]

Possibly

I only have a VN1500 book for an older model, somewhere out in the workshop................

Thanx mad dog! This is a 95 VN (A) model 750 not 800