Oil pressure and sending unit, my oil light is on

[FlyingAnvil]

Can anyone tell me where the oil pressure sending unit is? Let's say my wires are hooked up to the sending unit, can this be tested to see if it's accurate? How does one tell if there is good oil pressure and how many psi should these things produce? My idiot light on the dash just stays on and I don't want to run it till I figure this out. It sounds just fine when running and it did smell a little hot after a 12 mile trip. I did not realize that light was for oil till I was on this site because all the age and wear the only words legible is START engraved below the start button. And what are the 3 lights? I am guessing one is for neutral because it goes out when it's in gear.Thanks.

 

[Ruined1]

The lights are as follows:
Red: Oil Pressure Issue ("SHOULD NOT RUN THIS MOTOR" LIGHT)
Green: Neutral Light
Blue: High beam

I believe the OPSU is inside the case? Let me look into it... Did you download the manual and try looking for it?
http://www.xs400.com/forum/showthread.php?t=4503

 

[Ruined1]

and FYI the oil light SHOULD be on when you turn the key to show it's in working order. It should go away when you start the bike.

 

[Ruined1]

Page 3-18 of the service manual (available from the link I provided you)
OIL PUMP. not sure how to tell if it's working though... hopefully more advanced members of the site will chime in.

 

[FlyingAnvil]

You have been a great help thanks.

 

[Ruined1]

Not a problem buddy =)

If I may, what Y/M/m is it? Curiosity

 

[FlyingAnvil]

1980 XS400sg special

 

[Ruined1]

Sweet Ride... Maybe when you get'er cleaned up we'll see some pics =)

 

[FlyingAnvil]

O I have pics....this is the day I brought it home.. Didn't take me long to crack into it, had a rear brake shoe break in 3 pieces so I replaced that and added some paint..

 

[FlyingAnvil]

Here is a pic the same day with tank back on and cleaned up slightly.

 

[FlyingAnvil]

Looking at the oil pressure gauge thread I noticed the oil line running down and..Is this my Oil Pressure Sending Unit? Looks like an old Ford brake light switch..

 

[Ruined1]

That looks like a OSU to me... I remember when my OSU broke in my 1995 ford probe se and I tried everything to stop POURING oil all over the road... Finally the guy says try changing the OSU and i bought it... he handed me a cork with threads on it... I was like wtf? this is a OSU? it's like corking a hole that doesnt need to be there lol. again that was a car this is a bike im not certain.

Nice bike btw. =)

 

[drewpy]

Looking at the oil pressure gauge thread I noticed the oil line running down and..Is this my Oil Pressure Sending Unit? Looks like an old Ford brake light switch..

yep, it doesn't send anything, its just a pressure switch which grounds out the earth and lights the lamp!

I think its 1/8 BSPT don't overtighten as you will crack the engine case (its tapered)

 

[FlyingAnvil]

yep, it doesn't send anything, its just a pressure switch which grounds out the earth and lights the lamp!

I think its 1/8 BSPT don't overtighten as you will crack the engine case (its tapered)

Dig it, so I will first test the lead going to it and if that checks out, what is the most common problem with oil pressure on these? I mean a oil pump, bad bearing surface, oil journals being plugged, what could be the culprit? Maybe a bad switch? Thanks.

 

[drewpy]

I think you can take off the switch and push a nail head in there to operate the switch. The way I see it is, you got nothing to lose coz if its the pump, the bike will be out of action till you get a new one! If its the switch, just get a new one.

check out for grounding of the wire too, as that will light ya lamp!

 

[FlyingAnvil]

For sure, I undid the screw and it looked like the wire was grounded to the case. Mine was a victim of poor maintenance and I hope that will solve the problem. Now I need to rebuild the carbs and I just looked at the starter and not a wire one going to it, but I think the carbs have to come off to get the bugger out. Looks like more of a project than I initially wanted, but it is pretty easy to work on. I am a man with little time and working on these bikes is like my zen time so that's OK too.