Oil problem

[What?]

Can anyone with a similar air/oil cooled engine confirm how long it takes after switching off for the oil level to be accurate? The owner's manual says to wait for a few minutes. Ricky at Mt Eden said 10 minutes but this seems excessive to me.

10 minutes would be the go to be reasonably accurate, but 5 minutes should be near enough. I have found with my CB1100 that anything less than 5 minutes will give a very low reading. Even at 10 minutes, the level will be slightly lower than a cold reading.

[merv]

3. Try to drain the excess 1/2 litre or so of oil without losing the lot. Otherwise will do a complete oil change.

Siphon the oil to a bottle with a plastic tube down the filler hole - it doesn't flow as fast as thinner liquids but it still siphons - just go away and have lunch while its doing it and check occasionally how much has been transferred to the bottle.

[Dr Bob]

The only thing I would add, is that if the oil is hiding in the engine compartment somewhere - maybe a scavenging channel is somehow impeded by the internal mechanics - that when you stop the bike to check the oil, just stick it into gear and push it across the floor to turn the engine a little. This may dislodge any oil that has settled somewhere. Alternatively, is the surface your checking the oil on perfectly flat? maybe a little slope is keeping the oil somewhere, otherwise the logic of your problem defies me.

Two true stories about oil.

On an interesting note: When I lived in Eastbourne I stopped for petrol at a garage (back in those days it was more workshop and less service station, but still had a pump) and the young fella was out the front cleaning the concrete. It turns out some lady came limping in with a jag, her husband was going to change the oil before he went away on business and she didn't know whether he had done it. She saw a pack of oil next to the car so proceeded to fill the car until she could see the 'level' in the engine (as the description goes, this is the oil level in the rocker cover!). As she drove in to the township the frost plugs blew and the engine pumped every drop of oil onto the road. She arrived at the garage as the oil had emptied and the jag promptly seized.

On the other hand guys can be equally uneducated - my dad was a teacher at Naenae college, and one of the other male teachers came to work proudly stating that he had changed the oil in his car. ... but apparantly it was very difficult, and took a very long time. He had to somehow fit a tube to the oil filler, and connect that to a funnel. ?? thought dad. He got him to show him and found the guy had filled the car through the dip stick hole.

[Yarg]

Mike,
When i had my XJR I would wait 15 minutes before checking the oil.
not much help I know , but it seemed to take for ever till the oil filled to correct level.

[pete376403]

.
Two true stories about oil.
On an interesting note:
On the other hand guys can be equally uneducated - my dad was a teacher at Naenae college, and one of the other male teachers came to work proudly stating that he had changed the oil in his car. ... but apparantly it was very difficult, and took a very long time. He had to somehow fit a tube to the oil filler, and connect that to a funnel. ?? thought dad. He got him to show him and found the guy had filled the car through the dip stick hole.

Obviously the guy didn't know what the 7IO cap was for...

[speedpro]

If the oil feed circuit has a non-return valve which is playing up, sometimes the oil galleries might drain back to the sump and not others.

As far as affecting horsepower, I think it was a Honda 900 Boulder and there was 2hp differance between upper and lower levels of oil, measured on the dyno.

[MikeL]

Mike,
When i had my XJR I would wait 15 minutes before checking the oil.
not much help I know , but it seemed to take for ever till the oil filled to correct level.

That's interesting. I assumed that the XJR would be like the GSX1200 which gave a correct reading within a few minutes, but perhaps I just need to be a bit more patient...

[Redstar]

um had a prob on a bonnie once turned out to be the pressure relife valve in the oil pump sticking and was not allowing the oil to return to the sump.
but I,m sure its not that?

[MikeL]

Well, I siphoned out a bit of oil to bring the level back to just on the max line. Then rode on the weekend for about 600 kms total. Now the oil is about 3/4, so obviously some has been lost. Still no sign of a leak though and I haven't noticed any blue smoke from the exhaust. Just wondering, did anyone on the Sunday ride behind me notice any sign of oil being burnt?? (Shouldn't be happening at 17000 k, eh?)
I've booked the bike in at Mt Eden on Friday for a service and Ricky will have a look.

[mechanic]

yamahas use a sump oil level sensor, not an oil pressure sensor. they will quite often have the oil light come on when doing highway speeds because of the amount of oil that is being pumped around the motor which lowers the level in the sump.
if you fill the sump to just under the top of the oil level window instead of half way up ( which is where the level should be) you will still have enough in the sump not to trip the sensor. you must have miss read the oil level. oil cannot hide in a motor & then reappear at a later date. did you recheck when the motor was warm? the level will show slightly higher when it is hot.

[MikeL]

Well I had the oil and filter changed and since then have done 1500 km with no change in oil level so obviously there is no longer a problem, but I'm still a bit mystified about it.

[FROSTY:Me]

Mike -out of curiousity I'd suggest taking your air filter out.Follow your crankcase breather pipe up to where it joints the airbox. There will be a little foam filter there. Is that area wet with oil?
Looking back through my XJ notes I had almost exactly the same problem with an xj900 I had slightly overfilled with oil and somehow the breather was sucking oil up into the airbox then draining it back down into the crankcases.
I solved it in the same way you did and it had me scratching my head too.

[BM-GS]

Air/oil-cooled bikes can hide oil in the oil cooler. There are about 500 methods of verifying the amount of oil in a recent BMW boxer, but the only foolproof way is to drain it all out & measure it, then fill it up with the required quantity. (about 4 times, then take the average).

Most bikes have a sight-glass, which makes it easy to check regularly, but my GS can go from empty to totally full and back again on consecutive days... Paranoia-inducing? Yes.

Try keeping it on the sidestand until the engine's cool, then standing up on the centre-stand (if modern Jap motorbicycles come with such) and checking the level; or if that's what you normally do, try keeping it on the centerstand until cool and then measuring.

Best of luck, but I doubt there's really a problem (though best check, so you can sleep at night!)

[MikeL]

Thanks for those reassuring comments. I have been making sure that I only check the oil level when the engine has been stopped for at least 10-15 minutes, and it has stayed on full for 1500 km so I'm not worried any more. But I will have a look at the air filter if it's not too inaccessible.

[Motu]

If I filled my C50 with the correct amount of oil I would have trouble getting up my drive in the mornings,the oil was draging on the flywheels,so I learned to fill it just below the flywheels - this was the level on the dipstick,not the fill capacity,it's only on a small bike you can pick up these very small differences.