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Does anyone have a diagram/flow chart of the oiling system for the V11


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I have found a description in Guzziology that gives a description of the bottom end part of the system and have attached the accompanying pictures.


I also located in an old post from 2006 from Pete Roper this description:


 So lets look at how oil gets to your bearings.

Well, it starts off in the sump. In the case of the V11 'Broad Sump' motor the pick-up protrudes down to close to the bottom of the sump from above, through the gauze screen designed to take out the 'Big Lumps' should any suddenly appear! The pick-up goes more or less directly to the pump, this in itself is important because, and here is one of the most important things to remember when dealing with anything that is being pumped, THERE IS NO SUCH THING AS SUCK! The oil pump doesn't *SUCK* oil out of the sump, all it does is create a low pressure area within the pump body and the gas pressure within the crankcase will PUSH the oil up the pick-up and into the pump. Once the oil is through the pump it is then under pressure and being forced along mechanically but until it gets to the pump it is only being pushed by a fairly weedy sort of pressure. For this reason it is important to have as few impediments to flow as possible, that means a short, wide, gallery with as few bends as possible. While the pick-up on the V11's is quite nice and large the oil does have to turn through 90 degrees, twice, before it reaches the pump and the gallery in the block is no bigger than the earlier motors.

Once the oil is through the pump and pressurised it is sent to the filter where the bits are strained out, (we hope!) the good news is that Guzzi motors are very clean and there isn't much inside them to wear or shed bits of 'emselves and load a filter up. Once filtered the oil then passes on to the oil pressure relief valve which is contained within the oil filter/thermostat housing bolted to the bottom of the block. The purpose of the relief valve is simply to prevent the oil pressure rising too high either when the oil is thick and cold and possibly at higher RPM. The oil itself has internal friction and if the pressure is too high it will both sap power and also try to spin the bearings. While the 'Ring' type main bearing inserts Guzzi uses are not prone to this and the back clearance of the shells to rods also seems to be pretty good a spun bearing is a rare thing in a Guzzi, or any other engine, nowadays but it can happen. Maintaining the correct oil pressure also means that the filter won't become over-pressurised, pop it's gasket or explode, which tends to be messy!

After this the oil will pass over the thermostat which, when it gets hot enough, opens and allows the oil to pass through the cooler before going off for delivery to the bearings. From there on the oil simply has to get to the bearings and it does this through a series of galleries and pipework bolted on to the bottom of the block, essentially though it's very simple. After the thermostat the oil delivery is split. Some of it is sent to the front main bearing, some of it to the back. Both front and rear mains have a groove in the centre of the bearing face that allows some oil to circumnavigate these bearings and from there go on to the front and rear cam bearings. Also, above this groove, in the journal of the crank's front and rear main there is a hole drilled at a 45 degree angle in the crank itself that goes up to the crankpin. The crankpin itself is hollow and cross-drilled so that once the oil has filled the gallery in the pin it can flow out thrugh the big end bearings and out of the side clearance of the rods.

The camshaft too has a gallery running down the centre of it and some, but not all, Guzzi cams have cross drillings to allow oil that is forced up the inside of the camshaft to spray out and feed various bits like cam followers with oil by splash, Some of the more aggressive aftermarket cams even have cross drillings in the cam lobes themelves.

Finally oil travells up one further gallery to the top of the block above the front cam bearing where there are two drillings, one to take the oil pressure sender unit and the other one that takes the feed to the rocker gear in the cylinder heads.




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  • 2 years later...

Reading this well explained item, i wonder how far the oil level can drop without serious consequents for bearings and pistons. 

a friends (😇) V11 oil level had dropped to 2 litre ! His bike is still running smooth. 

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Basically it can fall until it's below the level of the pick-up.

Oil has three functions, to clean, to cool and to lubricate. As long as there is a supply it can do all three but the lower the volume the hotter it will run so the less well it will cool. The amount of contaminants in it will proportionally increase as the volume diminishes so it's like trying to wash yourself in dirty bath water. It will keep lubricating though to the bitter end. It's only when flow to the bearings is interrupted that chaos and destruction ensue!

Of course the lower the level the greater the chance on a V11 of the pick-up being exposed under acceleration and if that happens? It's all over Red Rover! In a matter of seconds!

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