Oil pressure switch

[Kaylock]

Hi, stupid questions but I'd appreciate any insight going.

I changed my instrument lights over to LEDs yesterday. I had several colours to compare, and halfway through the oil pressure light stopped turning on.

After checking the bulbs, bulb holder, wiring and connectors I did as the Haynes manual suggested and earthed the wire on the switch on the tank. The light came back on. Which, apparently, means my oil pressure switch is buggered.

So --

1) It seems very coincidental the switch died midway through my changing the bulbs. Could inserting the LEDs the wrong way have harmed it? (Is the switch even electrical?) Am I missing something else it could be?

2) If I replace the switch, is there any sign of a good one? There are plenty of secondhand ones available cheap on eBay (generally still in a spare clutch cover -- huzzah?), but I've no idea if they're any better than the one I've got.

Cheers,
Harry

[idordic]

Hey,

Have you tried switching the bulb around? If you connected it backwards the first time, it shouldn't have failed, that's from my experience though. Although it isn't impossible so I'd try a new bulb or take a working one from the neutral light(assuming you changed that one and it works) .

Also. Might want to put the old bulb back in and see if it works. Don't see how that would change something but it's worth trying.

Good luck.

[The Buddha]

Light goes off when oil pressure is over 3psi (I think its 3 psi). So start it and light should be off.
Cool.
Buddha.

[Kaylock]

Hey,

First thought I had was that the bulb had blown, but no such luck. Tried new LEDs, old normal bulbs, all rotations. Nothing works on the oil light, everything works on the neutral light. And the ones which 'don't' work do work when I earth the wire on the tank.

And yeah, the problem is it's not coming on even when the bike is off. 

Ordered a new switch since somebody made me a nice offer. Guess it's an excuse to change the oil.

Cheers,
Harry

[idordic]

Hmm, can you trace the wires from the switch to the bulb?
If the negative wire got damaged somewhere you'd get the exact issue you're facing. When you ground it somewhere on the bike and it works, that probably means one of the ground wire is damaged if the switch itself works.

Also check if the bulb socket has both wires soldered to it and if any of them came off, that happens if you pull hard on it.

[Bo72]

I have found that every now and then my oil pressure light stops working. All I have too do is clean the live wire connection on to the switch under the right hand crank cover and it then works fine.

[Kaylock]

Thanks for the replies. I was pretty confident it wasn't the wiring. With how many other things on the bike have rusted or fallen apart it was quite nice to find it in good condition. I actually wouldn't be surprised if I was the first person to have removed the crank cover. Practically pristine.

Changed the oil switch a week ago and that fixed the problem. Still don't know why it failed when it did but apparently I did bugger it up somehow.

A PSA for anyone else doing the same -- the Haynes manual insists you have to remove the 'pulse generator coil assembly'. But mine was held by some very stubborn JIS screws. Instead, if you just get the wiring out the way of the oil switch (either by disconnecting it up top or removing the two tinier JIS screws next to the rotor) I found you can force the socket past the plate by gently tapping it with a hammer. Much easier and no stripped screws required.