When does the oil pressure indicator lights up?

[ThePlayer]

Hallo ppl

Iam new to this forum and i would like to ask your opinion on this, i own an R1200GS and recently i had a serious problem with the engine oil. there was damage done to the valves and valve springs on my right cylinder, due to low level engine oil as the BMW dealership here in my country of CYPRUS claims. i told them the oil in my engine was approx. 2.5 liters. even if the oil as they claim is low, i asked them why the oil prssure light didnt appear on my display. the told me that if the oil pump is working then the oil light will not appear.

did it happen to any of you? did the oil pressure light appear? how much oil will be in the engine untill the light shows on the display?

thanx a lot

[RFW]

The level or amount of oil has no effect on the oil pressure light. Your mechanics apparently do not understand the basic principles of the oil system.

 

The oil pump sucks oil from the bottom of the motor. Even if you only had 1/2 the correct amount of oil (or even less) the pump would still suck oil from the engine, and pump it where it was supposed to go with no difference in operation.

 

There is a pressure sensor at the output of the pump that senses the pressure at the output of the pump. If the oil level is so low that the pump starts sucking in air, the pressure at the pump output will drop to almost zero, and the oil pressure sensor will switch on the oil light.

 

But as long as there is enough oil in the bottom of the motor, that the pump does not suck in air, the oil pressure at the output of the pump (and in all the oil system in the motor) will be normal.

 

If your oil light did not turn on when the motor was running, then oil was being delivered to the motor normally, and what your mechanicis claiming is impossible. oil level that is low will NOT cause a reduction in oil pressure, UNTIL the level is so low that the pump starts sucking in air.

 

Operating the motor with a low oil level will cause the motor to run hot, but that does not explain how only one cylinder was affected. Is it possible that an oil line to one cylinder head was blocked?

[ThePlayer]

Hallo my friend

the situation goes like this. i did the 20,000 km service while the odometer was at 20,800 km. on 24,052 the explotion was done and i explain. one morning with the engine cold, sitting from the previous night for about 12 hours, i pressed the start button and i heard a small explotion. the right cylinder was mulfuncioning, a very strange noise was coming from there and the bike didnt start. the next day i took it to the BMW dealership in Cyprus and from now on my problems began. the first day they told me the the right cylinder has been overheated because i left the bike running on the side stand...!!! WOWWWWW after some days they told me that the oil level was low and that is the reason. GO FIGURE... i wrote a letter to the headquarters in Germany explaining everything and iam waiting for their official answer.

I wrote in this forum to crosscheck what happens with the oil pressure light indicator if the oil level is low. the mechanic in the dealership told me the oil was approximately 2.5 liters but the service advisor insists that the oil level was low thats why the engine overheated and the valve was stuck open and the piston hit it.

what you wrote here seems very logical, we checked the oil pump also and they told me that it was working ok. their only answer is that the oil level is low and thats all.

iam waiting from the official answer from germany...

[Ken H.]

None of what this dealer is saying is making any sense. If indeed the valve crash was caused by overheating, which was from low oil, it would have crashed while the motor was hot not first thing upon start on a cold engine. And running the bike on the side stand has nothing to do with it either. If a bike could not maintain proper oil lubrication and cooling when leaned over, we'd all have broken bikes!

 

For whatever the reason the dealer is trying to avoid warranting a crashed valve. Do not accept this would be my advice!

[blkvelvt]

I agree. All oil systems draw from the bottom of the sump (wet sump system). The oil above the sump is just for volume and storage. The oil light pressure switch is after the pump. If the light did not come on, the engine had operating oil pressure. A low oil level is like a low gas level. Nothing changes until you run the pump dry.

[LuckyLeif]

...they told me the the right cylinder has been overheated because i left the bike running on the side stand...!!!

Any validity to this scenario?

[ThePlayer]

...they told me the the right cylinder has been overheated because i left the bike running on the side stand...!!!

Any validity to this scenario?

if this scenario was valid my friend, then everybody with boxer engines would have overheating right cylinders...

the most i left the engine running on idle mode is max 1 minute, just to rush in a bakery to buy bread or milk or something like that, thats all... sometimes when iam on the mountains i do the same thing just to drink fresh water from a water fountain. do u think, or does anyone think that by leaving the bike running on idle mode on the side stand for a minute or even two, we will get overheating right cylinders??? if this was the case then all boxer engines will be in the mechanics every day and BMW would go bankrupt, dont u think??? besides, why did the German put the side stand on the bike? why didnt he just leave the main stand??? why didnt he put a sticker on the side stand saying for example "danger if running the engine on the side stand"???

but my original question is still unanswered. did it happen to enyone, that the oil pressure light appeared on the display for any reason???

[RFW]

None of what this dealer is saying is making any sense.

That sums it up rather nicely.

[RFW]

...they told me the the right cylinder has been overheated because i left the bike running on the side stand...!!!

Any validity to this scenario?

Maybe the mechanic figures that when the bike is on the side stand, the right cylinder is higher than the left one, and the oil pump cannot pump the oil that high!

[JayW]

What about the low oil? Do you agree that the engine oil could have been that low? Had you checked it or added any in the 3000+ km since the last service? Had the engine been consuming a lot of oil in the first 20,000km of service?

 

It is clear that low oil of this degree will not cause low oil pressure, but allowing the oil to drop 1.5 liters below full is not good maintenance.

 

Jay

[blkvelvt]

I would like to use their sidestand theory and postulate this is the reason BMW stopped making the motorcycles with the "Brick" motors. The crankshaft would be up high and not get any oil on the sidestand.

Maybe they could fix your bike by mounting the sidestand on the other side of your bike?

[ThePlayer]

ok let me explain a bit more on what really happen

the bike is being used every day. on 30 of april was the last day i used it at 10 at night, with no problems or whatsoever. the bike on 6 may 2007 became 2 years old. next morning on the 1 may (while the bike was sitting for more than 12 hours overnight and the engine was obviously cold)) I tried to start the bike but it didn’t start. When I pressed the start button I heard a very loud and strange noise coming all over the bike and especially from the muffler. It honestly sounded like a small explosion. I was very terrified because I’ve never experienced anything like this before in my life. I tried to start it again but with no success. Once I pressed the start button there was a strange noise coming from the right cylinder. It sounded like the engine was malfunctioning. Immediately I called the mechanic and told him what happened. He told me to check several things all over the bike and everything seemed normal. We couldn’t find a solution through the phone and because that day was a public day in Cyprus (Labour Day) the next morning I called road assistance and took the bike to the BMW dealership in Nicosia.

A couple of days later the people from the dealership told me something very amazing to me: “the right cylinder has been overheated”…!! Wowwwwww

 

I asked why this happened and they told another SUPER AMAZING answer: “you might have left the engine running for a long time at the side stand and that’s why it happened”…

I asked how much oil was present in the engine and the mechanic told me that he measured approximately 2.5 LITRES…

It seems that one of the valves was stuck open in the cylinder head and hit the piston, and the piston hit back the valve. this is the damage of the bike, which seems very big since everything in the right cylinder has to be changed, except the piston and the rod.

several days later the service advisor came up with his final verdict, the damage was done due to low oil level...

Thats why i asked in this forum if the oil pressure warning indicator lights up if the oil level is low.

Does anyone think this damage was done due to low oil level (although the mechanik said it was approx 2.5 litres) or do we have any other suspicions on what really caused the damage???

[RFW]

It seems that one of the valves was stuck open in the cylinder head and hit the piston, and the piston hit back the valve.

Your mechanic is not too bright, it seems. Valve stems receive their lubrication only by drip and splash. They are not pressure-fed their oil by the pump. Even if the oil light DID go on, the engine would sieze up long before the valves would sieze open in their guides.

 

Does anyone think this damage was done due to low oil level (although the mechanik said it was approx 2.5 litres) or do we have any other suspicions on what really caused the damage???

IMPOSSIBLE. The oil light never went on, so the oil was still being pumped everywhere as usual, and the excess was splashing (AS USUAL) all around the valves, lubricating them in the USUAL WAY!

 

ALl that this low level of oil would have done, is to cause operating temperatures to rise somewhat above normal. But this would never cause a valve to sieze in its valve guide!