Oil pressure warning light on Norge1200

I have a 1200 Norge on a 08 plate (Frame number M113864)with about 35,000 miles on it
I have just had the throttle bodies balanced and what I thought was an errant oil pressure switch changed. When warm/hot eg in traffic, especially after a 13 mile run to work comprising dual carriageway with about a mile or mile and a half of filtering, when I stop at lights or similar and the engine idles, the red light and oil can symbol come on, blip the throttle and they go off. It never comes on at idle on a cold engine. I have heard that there were some early Norges with dubious oil pumps but after 35,000 miles surely they would have failed before now!?!
Anybody any ideas? Could be oil pump, engine doesn’t sound rattly of knocking, so I propose to get an oil pressure gauge hooked up to see what pressure the pump is putting out and take it form there. Anybody know what pressures I should be expecting? On other forums I have read that the relief valve can sometimes stick, and even the thermovalve being stuck and oil not getting to the cooler. Any suggestions/advice gratefully received. John

Brian LeCornau is the Nortge guru, he can be found on www.guzziriders.org, but he is on hols this week

He has helped me on two probs with my Norge

An update, I have connected up an oil pressure testing gauge, and get the following readings;
On start up with a cold engine (air temp was about 13C) the engine revs up to about 2,000rpm and the gauge shows about 2.5bar, very slightly over but not much which is about 35psi I think. As the engine settles down to an idle the pressure reading is 2bar at 1,200rpm, at this point the engine is still cold.
Letting the engine warm up at idle,(1,200rpm) pressure gradually reduces down to 1bar. Build up engine speed pressure increases showing 2.5bar at 5,000rpm. Let the engine speed return to idle the pressure drops to 0.5bar (10psi) when the engine is warm. So max pressure is 2.5bar at start up and when warm at higher revs (even at 6,000 6,500 rpm pressure never exceeds 2.5bar. Pressure at idle on a cold engine is 2bar, pressure at idle on a warm engine is 0.5bar.
What pressures should I be getting? I haven’t been able to find this information anywhere, (must be looking in the wrong places).

Further update, tonight I removed the sump and the crankcase/sump extender. Upon lowering the latter I noticed a piece of gasket missing, so checked the underside of the crankcase, not there either. The gasket was missing from around the three galleries which are vertically drilled through the extender and mate up with the three galleries in the crankcase. They appear to come from the pump and go to the cooler, the filter and to a transfer pipe. Would this result in a drop in pressure? I think it would as oil would be under pressure from the pump, get the this gap and some would ‘bleed’ off back into the crankcase/sump whilst the rest would continue into the lubrication system but at reduced pressure. I will remove the big ends to check for damage and if they appear to be ok, new gasket and try again.
PS how do upload photographs so I can show what I found?

Upload to Photobucket site (Its free) once on there click the picture and at the side ther will be a IMG code copy and paste the IMG code onto here and onece posted it will be converted from the code to a picture

Also some of the 3 holes you mention are on the suction side of the pump so they could be sucking in air resulting in the drop of oil pressure don’t forget you need new big end bolts and they don’t come with nuts they are a separate part also if you order big end bearings you need 4 of them not to as they are sold singular

Happy to say the gasket was the problem, for the princely sum of £3.50 I now have oil pressure in excess of 60psi at idle and 80psi at speed.
If the oil pressure warning light flickers it might be a good idea to check the gasket first. I’ve got a spare one in the garage in case it happens again, although I have heard a plausible explanation. Lack of use, not by me, I use it every day, but it only had 6000 miles on when four years old,this classic car buff suggests that gaskets do soak a bit of oil and get warm. They like to be wet, apparently, they get wet by the engine running and oil either in mist or other form penetrating them. If they dry out they are more likely to fail. Don’t know if it is true but sounds good to me!!
Thanks for all the advice and hope my findings are of use to somebody else.

Ah, what sump gasket?

I am guessing its this gasket, the upper sump gasket!






There was a shocking amount of mayonnaise type gunge in the oil pan, which was slightly shocking, considering that I have done more than 2000 miles on the bike and they have all been very long journeys, I would hate to see what one used for short journeys looks like,

I have ordered both the upper and lower gaskets, I wasn’t expecting them to rip on removal, but such is life and they were only just over a tenner including delivery!ianboydsnr2014-07-21 13:27:36

Note the oil ways inboard where the four ‘hidden’ screws go through, gasket is supposed to make a seal for them too. This why I guessed you lost pressure, a leak around either of them.

Well mine seems fixed as no low oil pressure recorded on the computer, ran fine all day, so renewing the gaskets seems to have fixed it,

Yippieee ianboydsnr2014-08-17 18:34:39

Good-oh

Hi ajay
Come across the same symptoms with my 07 Norge filtering and in long queues have you still got photos .Nearest Guzzi dealer to me is 120 miles so I might give it a go myself before a oil change.
Cheers
Tony Beecher

An air cooled engine will overheat without sufficient air blowing over it, ergo the oil will get very hot and thin. At low and idle speeds the pump pressure is so low it can’t keep the warning light off.