[Marshall]

I was riding on the freeway in 5th gear at about 7k RPM when the Oil light came one and the engine lost all power! Was pretty scary trying to get over to the side. Checked the oil, it's level is fine, and I have about 50 miles on the oil that I put in there like a month ago. Could running out of gas turn the light on? I don't think that's what it was because I've ran out of gas before and it's a little different (I shook the bike and heard some fluid anyway). What might have killed my bike, any suggestions?



Also I have asked a few things on here and you guys have always been a great help, weather I told you or not.

 

[lucky]

yep running out of gas does turn the light on at least on my 82 cx 500c every time i forget to switch to reserve and i putter to a stop the light is on and even though you hear gas in the tank your empty (depending on how much gas is in there) what you could try and do is lean the bike to the left(sitting on the bike) very far that way you can get it to the petcock and then into the carbs and then try that but it does sound like you ran out of gas

 

[Toehead]

So, did the did the bike lose all power, and when you put in the clutch the rpms go to zero and the oil light come on,



or:



did the oil light come on first, but the bike lost power and bogged while still riding at high rpms.





The order is very important. If you lost oil pressure while the engine was still turning, it could be very bad. I would guess a snapped oil pump chain or a spun bearing.

 

[Reg in Bristol]

Running out of fuel turns the oil light on?

WTF???

Nooooooooooooooooooo!



The only reasons I can think of for the oil light to come on

when riding is

A Low oil pressure, alarm bells should be ringing in here.

B Some later models had a bulb failure unit which lit the oil lamp when

a rear bulb failed.



If the engine stops and the oil light comes on thats Ok and quite normal

If the oil light comes on and and engine loses power or stops thats BAD!

If you have a late model with bulb warning unit, its operation should have

no effect on the running of the motor.



No models except the Euro have fuel gauges and even then theres no

reason for the oil lamp to light if the fuel is low or non existant.

 

[lucky]

Running out of fuel turns the oil light on?

WTF???

Nooooooooooooooooooo!



The only reasons I can think of for the oil light to come on

when riding is

A Low oil pressure, alarm bells should be ringing in here.

B Some later models had a bulb failure unit which lit the oil lamp when

a rear bulb failed.



If the engine stops and the oil light comes on thats Ok and quite normal

If the oil light comes on and and engine loses power or stops thats BAD!

If you have a late model with bulb warning unit, its operation should have

no effect on the running of the motor.



No models except the Euro have fuel gauges and even then theres no

reason for the oil lamp to light if the fuel is low or non existant.

ok i should of said it differentially the motor stops and then the oil light comes on.........or also when i stall it out (i havnt done that for a while now) lol

 

[marshallf3]

That's normal. If the engine quits turning then the oil pump obviously stops as well and the pressure will head back to -0-

 

[Toehead]

That's normal. If the engine quits turning then the oil pump obviously stops as well and the pressure will head back to -0-

unless he means the oil light came on while running and the engine subsequently froze up.

 

[lucky]

thats a good question to the OP was there any strange noises??

 

[Blindstitch]

The bulb failure unit was only in the 79 cx500's. Maybe the 78's but i'm not 100% sure.

 

[bandit]

Running out of fuel turns the oil light on?

WTF???

Nooooooooooooooooooo!



The only reasons I can think of for the oil light to come on

when riding is

A Low oil pressure, alarm bells should be ringing in here.

B Some later models had a bulb failure unit which lit the oil lamp when

a rear bulb failed.



If the engine stops and the oil light comes on thats Ok and quite normal

If the oil light comes on and and engine loses power or stops thats BAD!

If you have a late model with bulb warning unit, its operation should.......

Reg,i was under the impression that it was the early models,78,s and 79,s that had this daft idea

 

[bear351c]

This is very confusing...



If the engine stalls (runs out of fuel) the oil light comes on. Normal.



If the oil light comes on with the engine running, for ANY reason, ride no more.



For all the newbie's out there. Hope it helps.



As stated, common fault in a CX Big end bearing shells rotate.

 

[Marshall]

It was out of fuel.... newbie move! Thanks guys!

 

[bandit]

It was out of fuel.... newbie move! Thanks guys!

definately easier to sort out compared to the oil light coming on because of lack of pressure within the block.....lol

make sure you check your oil regularly

 

[marshallf3]

He later clarified the post that the engine stopped then the light came on.



I'm quite unsure how they could sense low fuel on these things, I'm still fighting trying to make a decent gas gauge by "pinging" the tank with an ultrasonic pulse and looking at the waveform returned depending on fuel level but research time just isn't there at the moment, I've got to get these other projects finished first, the gas gauge one is going to take a lot of time and posibly some $$ before I can even decide it if it's feasable to mess with.



Obviously I'll want a sensor that attaches to the outside of the tank in a hidden area. It would work by computing how much empty (air) space is present then subtracting that volume from what the tank holds when it's full. It will probably require a microcontroller (tiny dedicated computer) as well as writing a complex program and I'm not too good at that.