Oil Pressure Light

Hi everyone,

This is my first post here. I'd appreciate if I could get some advice. I just bought a 2013 GRiSO and 10 minutes into the ride home, in hot city traffic and hot and humid weather, saw the oil pressure warning light come on briefly and then turn off. After some more experience with it, here is how it happens:

It's always fine when riding, and always fine when idling, and always fine for the first many (10 or more) minutes after riding on a cold engine. If you blip the throttle at idle (whether stopped or at speed putting it into neutral), it comes on as it hits 1500rpm. It also comes on after coming to a stop, idling, and then accelerating, as the needle hits 1500rpm. It then turns off shortly after by around 2000rpm. It also comes on if you ride it slowly in gear at 1500rpm, whether from idle, or slowing down from a higher speed. Again, once it passes around 1700-2000rpm, it shuts off. Or if you blip the throttle while idling, past the 1500rpm mark, it comes on and stays on until you get it past the 1700-2000rpm.

No weird sounds from the engine. The previous owner had not ridden the bike in the couple of years he owned it so he wouldn't have known about it. He kept it stored in a pristine garage. The problem either started in the time the bike was stored or perhaps the owner before that had seen it.

After I got home, I noticed that in the box of stuff I got with the bike included a ziploc bag with a brand new oil pressure sensor. I did my research on the board and found that this could be the culprit and wondered if the original owner (prior to the one I bought it from) had been getting ready to replace it or if he just had it as a spare.

So I installed the new sensor. The problem looked solved after a longer 25 minute ride in the country (no traffic) with plenty of stops, idles, 1500rpm tests etc. But then, just as I was pulling back into the garage victorious, bang! it came on at 1500rpm.

I'm not sure what to do next. Could the oil pressure switch I found in the bag be bad (it was brand new)? Should I buy another?Could it be a wiring connection issue? Is the next thing to try, to replace the upper gasket in the sump (as I read on the boards)? Or should I take it to a dealer to have them check the oil pressure and perhaps change the oil pump if that is the issue?

Thanks -- your help is much appreciated.

One more item that I only noticed now: There is a bit of oiliness at the bottom 2-3 inches of the front of the sump case. I wonder if that could point to a leak at one or both of the gaskets, which could perhaps mean that the internal one has a leak which is affecting the oil pressure. Perhaps, with the bike sitting for almost two years, the gaskets at the sump deteriorated. I did read on this board, that the internal gasket could cause oil pressure issues.

The most likely cause of the problem is going to be a blown it spacer gasket between the sump spacer and the block. The factory gasket is very thin and frangible and can easily fracture and get pushed out leading to oil pressure being lost. This is a serious issue and can lead to big end damage and/or failure so it should be addressed. The gasket should be replaced with the thicker aftermarket type that allows for greater crush and more effective sealing.

Note that this is NOT the sump gasket, (Although this too needs to be replaced when the sump is removed.) but the gasket above that between the spacer and the block.

Another possibility is the oil pressure sender switch but in this case I'm leaning towards the gasket being the issue.

Thanks so much for the quick reply, Pete. Much appreciated. I will source the sump spacer gasket and the sump gasket tomorrow and will keep the bike parked till they arrive. I'll aim for aftermarket ones made from either metal or silicone. Seeing the bit of oily mess at the front of the sump pan really seems to point to what you said and gives me hope of an easy solution.

Cheers!

Nope. The oil galleries are internal. There will be no external sign if it has blown out.

The thicker aftermarketgaskets are available from MG Cycles among others. They are generally green in colour. I would advise against a silicone type gasket in this application.

Pete Roper wrote:

Nope. The oil galleries are internal. There will be no external sign if it has blown out.

Pete, does this mean that the oil pressure light is the only giveaway that this seal has blown?

The light, in hot weather and extreme cases you get the 'Oil Can' icon at the bottom of the dash and in time the rods will start to knock as the big end shells wear and the oil can no longer wedge. There is no external leakage, no sign detectable by just gurning at the motor as it sits there. There is no drop in oil level as it's all still 'In there', it just isn't getting to where it needs to work.

And it's not a seal as is usually known as a seal. It's a gasket. If you search the issue you'll find a fucktonne of info on it. It's State of Origin footy tonight but if nobody else gives you a link I'll repeat post the whole thing again. Perhaps I should do a pictorial and explanation so it can be posted in the Tech area but it is tedious endlessly repeating stuff.

Ok, point taken Pete. Thanks.

Pete Roper wrote:

The light, in hot weather and extreme cases you get the 'Oil Can' icon at the bottom of the dash and in time the rods will start to knock as the big end shells wear and the oil can no longer wedge. There is no external leakage, no sign detectable by just gurning at the motor as it sits there. There is no drop in oil level as it's all still 'In there', it just isn't getting to where it needs to work.

And it's not a seal as is usually known as a seal. It's a gasket. If you search the issue you'll find a fucktonne of info on it. It's State of Origin footy tonight but if nobody else gives you a link I'll repeat post the whole thing again. Perhaps I should do a pictorial and explanation so it can be posted in the Tech area but it is tedious endlessly repeating stuff.

Is there always some warning like the rods knocking or can this near-instantly destroy the engine? Or is it more of a gradual process of engine wear taking weeks/months/years?

Went through oil light situation on 14 Norge. Without finding information I changed sending unit, then added oil pressure gage. Pressure was good start up and above idol. Once warm dropped off to 0. So I bought and installed oil pump (af1). Fired up same problem. After reading through hours and years of different guzzi forums a guy named Phil explained the gasket between block and spacer. Stock gasket is thin and brittle with pieces blown out allowing the oil to shoot out into the pan instead of going up through the motor. $12 gasket oil and filter f’n fixed! While the Norge was down the ‘13 GRiSO came down with the same symptoms. Starting with a flickering oil light after a hard run. Good thing I bought two gaskets.

I thought I would add to this thread instead of starting a new one. I have a '13 GRiSO w/6k miles, oil light came on while cruising; shut bike off, check that there is oil in it -- OK, no weird noises. Ride about 1 mile home. I replace the oil pressure switch, no change, I let the bike idle for a couple minutes, seems like the top end is getting a little louder, shut it off. Remove the oil pan and sump spacer. Spacer gasket is intact as are the oil pick-up o-rings. What's the next place to look? Oil filter was a UNI and 3 months old and intact. Running Motul 10w60.

Oil pressure relief valve and oil pump gear.

How would I go about testing the oil pressure relief valve ?

Remove it and use an air line with a gauge on it. Simply disassembling it and making sure the piston moves freely and the spring is intact would probably be good enough.

The fact the light has come on is worrying. I'd be seriously concerned about the oil pump gear as I have seen one fail. Luckily the owner shut it down immediately and there was no damage done.

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I agree, extremely concerning. Sorry for my ignorance Peter as I haven’t had one of these apart. Spring is intact, piston appears seized, looks like in its present state and it would bypass back to the pan

Well, there's yer answer. Free it up and remove the piston and check the bore. If it's all smooth and you can slide the piston through it's whole travel freely and it seats firmly it's probably good.

The bad thing is if you ran it long enough to become noisy your bottom end is almost certainly shot.

Sorry not thinking clearly, piston was all the way down, so it would have been in the seated state.

I guess pump gear is the next place to look? Requires removal of the front timing cover correct?

Agreed about the noise, I would like to inspect the rod bearings at a minimum. Are the bolts torque-to-yield on the bearing caps? What is the torque spec for install?

Pete Roper wrote:

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How the hell did you get beer out of that gear Pete?

Tread them like grapes for wine Tony.

nateshoe22 wrote:

Sorry not thinking clearly, piston was all the way down, so it would have been in the seated state.

I guess pump gear is the next place to look? Requires removal of the front timing cover correct?

Agreed about the noise, I would like to inspect the rod bearings at a minimum.  Are the bolts torque-to-yield on the bearing caps? What is the torque spec for install?

Yup. Tank and alternator off. Timing chest off and there it is.

Note thet if the inside of your timing chest looks like this.

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It's a really good idea to get it blasted before reinstalling it. With a new seal obviously.

If you can find one an early steel oil pump gear is a better idea than the later plastic one.

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Bingo. Any idea what model year I should be looking for to find a steel gear?

Also what is the torque spec on the rod bearing caps? Want to remove them to inspect.

'08-09 GRiSO and probably Stelvio for the steel gear. From memory rod bolts are 38 ft/lbs but check that in the manual. I haven't done rods for a while.

I've just checked the current parts list and all model years seem to use the same number now for the gear. I know that a few years ago there were two numbers and I've actually got a steel gear at the workshop in its original packaging so it might have its part # on still. And no. It's not for sale. It's going in the Green Horror at some point as it has a 2012 motor with a plastic gear in it.