calling all gurus

[xschop]

Serious question here...Since I don't have the original gauges on my 79F 'Blue Streak", can I hook up an oil pressure warning light to the oil pressure sending unit directly, or does that thing have to go to the brain box first then on to the gauges?.... Thanks to all in advance

[Winterhawk]

Just run a positive wire to one side of the light. A negative side to the sending unit. It will work fine.

[xschop]

sending unit

so the sending unit is not tied into the brain box?

[xschop]

Ah-Ha

so you mean a battery positive to the light, then from the light negative to the sending unit?

[tab1324]

If you want guages, I've got em

check on ebay for the gauges I'm selling if you're interested. They're from a 78.

Tom B.

[xschop]

oh boy

Thanks, I have 3 sets of guages, none look good on Blue Streak.

[John]

Re: Ah-Ha

Originally posted by xschop
so you mean a battery positive to the light, then from the light negative to the sending unit?

The OP sender just makes ground for the dircuit. Just make sure you have it in a switched circuit, or the light will stay on when ever the engine isn't running, and the ignition switch is off.

[xschop]

ground

I thought that the OP sender makes ground when the oil pressure goes down to a certain level, triggering the light. If this is true the light should only come on at low pressure, no matter if it is wired straight to the battery?

[John]

I believe the light will come on at around 2-5 psi. It's nothing more than a pressure switch. When there is pressure, then the path to ground is broken, hence no light.

[xschop]

now that makes sense

I will hook it up this weekend

[randy]

I thought that the OP sender makes ground when the oil pressure goes down to a certain level, triggering the light. If this is true the light should only come on at low pressure, no matter if it is wired straight to the battery?

You're absolutely right.

What John tried to tell you is, if you wire it directly to the battery, the light will be on even if the bike is off!

[xschop]

another ah-ha

Thank you both. I wasn't thinking about low/no pressure when bike is off. So which fuse should I run it off of?. Also what is the normal oil pressure when bike is running? I just want an idiot light on my tree...thanks again

[mro]

oil psi

cruising speed oil pressure 42 psi

oil warning light actiation 4.2 psi

relief valve opening 70 psi

cruising speed 55 mph
oil temp 216 F
___________________

Good book doesn't say psi at idle
(well....... if it does, I didn't find it)


mro