Ducati Monster Forum

Moto Board => Tech => Topic started by: LYD on January 22, 2013, 04:20:06 PM

Title: low oil pressure light at idle
Post by: LYD on January 22, 2013, 04:20:06 PM
i have a 2001 900 monster, i had the clutch cover vented, then replaced the seal, new clutch, basket,...etc    put it back together filled with oil and now low pressure at idle, any ideas???  when the bike is running the sight glass is full of oil and I cant see the level, but as soon as I turn it off it drops between the marks?  ???
Title: Re: low oil pressure light at idle
Post by: Speeddog on January 22, 2013, 05:14:20 PM
I suspect you didn't fit the small O-ring that seals the oil gallery from the block to the cover.
Title: Re: low oil pressure light at idle
Post by: brad black on January 23, 2013, 12:30:26 AM
you're talking about level, not pressure.  if the light is off it has pressure and it's fine.
Title: Re: low oil pressure light at idle
Post by: LYD on January 23, 2013, 03:04:02 AM
Quote from: Speeddog on January 22, 2013, 05:14:20 PM
I suspect you didn't fit the small O-ring that seals the oil gallery from the block to the cover.

i made sure the o ring was there.  i took the smallest amout of grease to hold it to the block, while i put the cover on,  but this is what I was affraid it might be. its the only thing it could be, besides the pump.  Thanks

Quote from: brad black on January 23, 2013, 12:30:26 AM
you're talking about level, not pressure.  if the light is off it has pressure and it's fine.

the pressure light comes on at low rpm.  I was just explaining what conditions i have.


anyone else have any ideas, before i tear it down again??
Title: Re: low oil pressure light at idle
Post by: DucHead on January 23, 2013, 03:32:39 AM
Loose connection in the sensor?
Title: Re: low oil pressure light at idle
Post by: Howie on January 23, 2013, 03:35:06 AM
Put a mechanical gauge on it before doing anything else.  It would be a shame to find out later it was a bad sensor.

Cold engine:
at 7 100-7 300 rpm: at least 2.5 bar.
at 3500-4000 rpm: between 4 and
6bar.

Hot engine (140°C):
at 1100-1300 rpm: at least 1. 1 bar.
at 3500-4000 rpm: between 4 and
6 bar.
Title: Re: low oil pressure light at idle
Post by: Slide Panda on January 23, 2013, 05:46:12 AM
Listen to Howie (always)

But a while back I had a similar situation and it was due to a leak and low idle. I put a gauge on it and was just below spec at idle. As noted I did have a leak - it was actually between the main case as alternator cover, near the clutch slave. Also my idle was down in the 800-900 rpm range. Recommended on a 900 is about 1200.

But as noted, you've probably got a leak some place. But should verify your pressure numbers.
Title: Re: low oil pressure light at idle
Post by: LYD on January 23, 2013, 01:52:43 PM
I changed both side case gaskets, all 4 valve cover gaskets, and the 2 cam cover gaskets.  ran it yesterday, and no leaks today.

where do I get a mechanical guage at, that will work for me?

I really dont want to tear down that whole side if I dont need to just for that little o ring, but if I must, I will.

The sensor could be bad, but it was working fine before I tore it down.

I will try to get a guage that will work before I do anything.
Title: Re: low oil pressure light at idle
Post by: LYD on January 23, 2013, 02:47:43 PM
crap, i just went to the garage and noticed there are 4 other ducs, take a sensor out of one of those.  so we'll see.
Title: Re: low oil pressure light at idle
Post by: LYD on January 23, 2013, 03:31:29 PM
well light still comes on, but only after it gets warm.  looks like tear down again.  anyother suggestions before i tear it down??
Title: Re: low oil pressure light at idle
Post by: brad black on January 24, 2013, 03:00:02 AM
oil flows through the cam covers and the primary drive cover.  there is a seal that seals the rh end of the crank, check that also.  if is fitted what appears to be the wrong way, except in testasrettas.

quite a lot of the engines would show the light at a hot idle.  it just means the pressure is dropping enough to trigger the switch.  my 750 will do it.

but a 2001 should have the later pump gear ratio, which spins the pump a heap faster.  they have a lot more pressure.

i have seen 996 do it because the drilled oil feed screw in the lh side of the cases has fallen out and is sitting at the bottom of the alt cover.

if it was ok before you played with it assume you make the beast with two backsed something up.  that's what i always do.
Title: Re: low oil pressure light at idle
Post by: clubhousemotorsports on January 24, 2013, 09:18:54 AM
Quote from: brad black on January 24, 2013, 03:00:02 AM

if it was ok before you played with it assume you make the beast with two backsed something up.  that's what i always do.
That's always been my experience also.
Title: Re: low oil pressure light at idle
Post by: LYD on January 24, 2013, 04:00:58 PM
and the winner is Speeddog!  
Quote from: Speeddog on January 22, 2013, 05:14:20 PM
I suspect you didn't fit the small O-ring that seals the oil gallery from the block to the cover.

i tore it apart and the o ring was out of place.  put it back and now no light.  Thanks everyone!