F800GS (2008) Oil light flashing

[mike d]

Hi all,

I had a call from a BMW Club member about a problem with his F800 GS (2008). He was waiting at traffic lights and as he began to accelerate away the bike stalled and the engine cut out. He turned the ignition off and back on and watched the usual self check sequence and tried to restart the bike. It wouldn't start. He then noticed that the oil light was flashing all the time.

He decided to have the bike recovered as he didn't want to ride it if there was low oil pressure. At home he started to investigate and found the fuel pump to be failed, which he replaced. I lent him a GS-911 to have a read of the faults, which he did before resetting them (no he didn't make a note of the faults). So no faults recoerded, but the oil light was still flashing.

Thinking it was a faulty sensor he bought another one and fitted it. The same problem of the oil light flashing was still there. Using the GS-911 Output Test functions he exercised the instrument cluster, but noticed there was not a test for the oil light.

He had a few distractions along the way in that when he replaced the oil sender he incorrectly installed the throttle cable in the outer groove of the mechaniosm, so when he went to start the bike it immediately revved up. He was at the time wanting to start the bike so that it relearned the adaptations as he had fitted a replacement idle actuator (another distraction).

So if the GS-911 doesn't have an output test for the oil light, has anyone come across this flashing issue before, and if so, what was the cause.

Thanks in advance for any help.

Mike 

[Jughead]

Yes.  I have had 3 bikes with this issue.  The last one was one of the new F800s that doesn't have the oil pressure sensor.  That led to an engine seize.

The cause on all three bikes was a broken oil pump drive gear.  Remove the LHS engine cover (clutch side).  You should see pieces of the plastic gear lying around.

[mike d]

Hi Jughead,

I was hoping you would be around!

Thanks very much for the information, I phoned the guy this morning just to warn him to not start the engine, and have sent the pictures you posted.

I will update the forum once he has had a chance to investigate.

Any idea what causes the failure?

Mike

[Jughead]

Poor quality materials the gears are made of.

[mike d]

Just to put this topic to bed.

The chap had a fitted the throttle cable incorrectly hence the high idle speed. Once that was sorted it was found that the oil light flashes as part of the initial 'pre-ride checks, so when he did eventually start the bike all was well, and the oil light extinguished as expected.

He also performed the adaptations reset, and the bike runs fine. He has not been out for a longer test ride as it needs to go for the UK MOT test (yearly roadworthy test for vehicles over three years).

Thanks for the helpful replies.

Happy new year!

Mike   

[Jughead]

[emoji106]

Thanks for the feedback. 

I am intrigued though as to why he removed the throttle cable to replace the oil sender unit in the first place.  On the 800 the oil sender can be replaced in 5 minutes by only removing the small triangular cover on the LHS of the bike.  No need even to remove the battery cover.