Headlights keep blowing

[Stig]

This one puzzles me. I have an idea what the issue is but am looking for clarification.

I keep blowing my headlights. When the headlight blows I am forced to use the main beam. It's not long when this blows as well. The sidelight bulb however never blows. When I say it blows, the elements are broken.

I originally thought it was the wiring block as I know there were dodgy connectors in there. But I have now withdrew the wires from the block and soldered the wires direct to each other, in effect I have by-passed the block.

I then wondered about vibration but this is not the cause. It started on my twin fighter lights (blowing both bulbs) and has carried on with the new headlight I have now. I know it is not the wiring as when changing from the old lights to the new, all the connections in the headlight have been done again. New solder, good connections and proper heat shrink wraps used.

As I said, I have an idea what the issue is but will wait to see if people back up my thoughts before stating what I think it is. I can do without those that second guess and jump on the bandwagon and agree with what someone else says just because that other person seems to know what he/she is talking about.

So after that, is there anyone out there going to step up and give a considered and knowledgeable suggestion ?

[Alpinestarhero]

My haynes manual for my SV suggests that constantly blowing bulbs are a sign of the regulator/rectifer beign faulty.

Have you had any blown fuses aswell?

Matt

[Stig]

My haynes manual for my SV suggests that constantly blowing bulbs are a sign of the regulator/rectifer beign faulty.

Have you had any blown fuses aswell?

Matt

No other faults. No blown fuses, nothing. Just the headlights blowing.

[Razor]

What's the DC output Mr Ape?

[Alpinestarhero]

No other faults. No blown fuses, nothing. Just the headlights blowing.

Hmm...blown fuses would add strength to the argument that its a faulty regulator; don't go on my sugestion just yet then.

Matt

[Stig]

What's the DC output Mr Ape?

Don't know. Something I intend to investigate at the weekend.

[padmane]

Too much current through the bulbs will burn them out. Change the regulator. See the Haynes manual page 9.31 :)

[Ruffy]

At the risk of "jumping on the bandwagon", I too would suspect the regulator if, as you say, the wiring is OK. I suspect over voltage (therefore driving too much current, which is a nightmare for filament bulbs) which is what the engine alternator will produce when run at speed, easily up to 15V+ unregulated.

Do you get the same problem if you leave the lights on without the motor running? If not, this would add weight to the over-voltage theory. If you've got time to recharge (as, unfortunately it will run the battery flat quite quickly), perhaps try it one evening or overnight to see how long they last.

[Ruffy]

No other faults. No blown fuses, nothing. Just the headlights blowing.
If it was a really serious voltage problem, then you'd expect other bulbs and/or fuses to blow, but it's possibly just a weird combination of the higher power headlight being just sensitive enough to react to the increased current caused by a small over-voltage.

Fuses are surprisingly tolerant to small overloads. The high beam may be robust enough to cope (being even higher wattage filaments) and the lower power tail light etc may have sufficiently higher resistance to survive for longer.

Sounds tenuous I know. As suggested previously by others, you really need a meter on the terminals to check the voltage.

[getyerkneedown]

At the risk of sounding patronising/stupid, when installing the bulbs are you being careful not to actually touch the glass bulb? I only say as a friend of mine had the same problem, bulbs constantly blowing, and turns out he was always handling the blub and touching the glass... which of course gets grease on it causing hotspots.

Just my tuppence worth.

[ejohnh]

Are the main/dip lights protected by a unique fuse? Not that that would shed any light on it. You would think that if the reg was not regging properly then there would be more bulbs/fuses blown. Could it be intermittently faulty earth?

[Quiff Wichard]

hope you get it sorted Si..

but I think this is the problem

pointing the lights skyward and them straining to get to the moon..


http://i22.photobucket.com/albums/b326/sigourneysbeaver/DESKTOPS026.png







serious hope it sorts out

[Blue_SV650S]

Its an aftermarket headlight right?

Could simply be vibration/poor design.

Or has been suggested by others, regulator and bare fingers on the glass are possibilities.

As no other bulbs are blowing, I'd go for vibration or fingers myself .. but I’d also be straight in there with a multimeter checking the running voltages ;)

[Stig]

I'm still listening to suggestions.

To add a bit more info.

The problem started a long time after my twin headlights were installed. The problem has carried over with the new normal headlight I have installed. So this discounts vibrations. If it were vibrations, it would have done this a long time before with the old headlights. On top of this, I have used rubber washers to take out any serious vibrations.

Touching the bulbs. No. I know how to install them correctly. This is not the issue.

So far everyone who has suggested the regulator / rectifier are on the same train of thought as myself. I have not seen any other suggestion that would make me think of anything else. So at the moment I have to believe it is this. I shall check the the voltage tomorrow some time. If anyone else wants to suggest something I have not thought about, feel free to enlighten me.

[ASM-Forever]

Get a R6. HTH.

:)

[Ruffy]

BigApe, Had any luck tracing the problem?

[ridelikeaturtle]

Are the lights brighter than normal (obviously, before they blow)? Sounds like too much voltage to me. Get out the multimeter and start checking outputs, wiring, yadda-yadda.

[ASM-Forever]

BigApe, Had any luck tracing the problem?

Well he arrived at tonights meet with a functioning headlight. The real question is will he make it home? :D

[Stig]

BigApe, Had any luck tracing the problem?

I think I now have it nailed down. The reg/rec is working fine. It's not that. The last time I put a new bulb in (just before arriving at the TVSF meet) the headlight wasn't working but the main-beam was. A prod of the connector block on the left hand side of the bike and the headlight came on. I gave it another wiggle and the headlight came on/off/on again. I believe corrosion has got into the block. I will cut the block out and solder all the wires on Sat.

I'm assuming the corrosion has led to shorting of wires.

Sod's law. Since diagnosing the suspected fault, the headlight remains lit. :lol: I shall do the by-pass surgery anyway.