How much oil does my oil pump push?

[Smoky]

Does anybody know how much oil my hexhead oil pump pumps?

 

And is this a lot compared to other bikes, or other models of BMW.

 

Do our oil cooled bikes have large pumps capable of pumping lots of oil?

 

If we are moving lots of oil, does this require oil filters capable of extra heavy service?

[Dave_zoom_zoom]

Does anybody know how much oil my hexhead oil pump pumps?

 

And is this a lot compared to other bikes, or other models of BMW.

 

Do our oil cooled bikes have large pumps capable of pumping lots of oil?

 

If we are moving lots of oil, does this require oil filters capable of extra heavy service?

 

I think those are some interesting questions Smoky.

 

Your profile doesn't tell me which hexhead you have. Mine is a 06 R1200RT. Maybe all hexheads are the same re: oil systems. I don't know.

 

My understanding (which may be wrong) is that I have 2 oil pumps on a common shaft. I would guess that the one serving the oil cooler may be a low pressure - high volume pump. Where the pump that lubes the engine would be a high pressure - (maybe) a lower volume pump.

 

I hope your questions will be more properly answered by one that knows more than I.

 

If I'm on the right track (or not) I'd be interested as to what volume & pressure rates these pumps might be producing.

 

HOPING TO HEAR FROM OTHERS!

 

MERRY CHRISTMAS

 

Dave

 

 

[T__]

Smokey, (you get that handle from owning an old K bike?

 

As Dave mentioned 2 oil pumps,, one cooling & one high pressure for engine lubrication.. The BMW does run fairly high oil pressure but nothing outstanding compared to other high performance applications.. A good engine lubrication oil pump general rule is 10 psi per 1000 rpm's so within reason most stay close to that rule (at least at normal operating parameters)..

 

 

Twisty

[RSR]

There is nothing in the manual about volumes it does how ever have specs that engine oil pressure is between 24 and 42 psi, The warning indicator comes on below 3 psi. The cooling pump rotor is almost 10mm thick well the lube pump is almost 12mm.

[T__]

There is nothing in the manual about volumes it does how ever have specs that engine oil pressure is between 24 and 42 psi, The warning indicator comes on below 3 psi. The cooling pump rotor is almost 10mm thick well the lube pump is almost 12mm.

 

 

Rory, where did you get those oil pressure specs? My BMW manuals shows both the 1150 oil head & 1200 hex head operate at 3.5-6 bar (50.7-87 psi) at 80°c oil temperature.. It also shows the oil by-pass valve opening at 6 bar..

 

Twisty

 

 

[RSR]

Sorry I used the wrong convertion from bars and ended up out by half.

[GordonB]

Smoky had a good question here. Many who use aftermarket filters, and even some who've had warranty issues, never ask the question of how much oil/minute is pushed through that filter and is that (aftermarket) filter designed to handle that spec? Sure a 'filter' may fit to the bike, but is it able to handle the amount of oil and pressure being sent through it?

[smiller]

Smoky had a good question here. Many who use aftermarket filters, and even some who've had warranty issues, never ask the question of how much oil/minute is pushed through that filter and is that (aftermarket) filter designed to handle that spec? Sure a 'filter' may fit to the bike, but is it able to handle the amount of oil and pressure being sent through it?

I'm not aware of that spec ever being formally measured or published for automotive oil filters, implying (to me) that it's not much of an issue.

[Ricoshay]

Smoky had a good question here. Many who use aftermarket filters, and even some who've had warranty issues, never ask the question of how much oil/minute is pushed through that filter and is that (aftermarket) filter designed to handle that spec? Sure a 'filter' may fit to the bike, but is it able to handle the amount of oil and pressure being sent through it?

I'm not aware of that spec ever being formally measured or published for automotive oil filters, implying (to me) that it's not much of an issue.

 

There is one seldom available rating that I believe is important. The pressure drop at which the internal bypass valve opens signifying a plugged filter. That's the primary reason that I want to know that the filter manufacturer specifies the filter is designed for use on my bike.

 

The number exists and is part of the design specifications, but I don't know whether they vary much from filter to filter. Does anyone know??

[smiller]

The number exists and is part of the design specifications, but I don't know whether they vary much from filter to filter. Does anyone know??

When I have been able to dig up that figure it doesn't seem to vary much, just a few psi here or there. I don't know whether that's because a few psi makes that much of a difference or simply because a manufacturer comes up with a number (that end up being very similar, hence the small variance) and the filter manufacturer just matches what the manufacturer quotes. I seem to remember that the bypass spec difference (one of the few cases where I could find one published) between a Fram automotive filter and the exact same Fram filter for motorcycle applications (sold in motorcycle shops and painted blue) varied by 3 psi (9 vs. 12.) Where did the 3 psi come from? Who knows. Maybe Honda or some other manufacturer picked that spec and it became attached. But I'm going to make the rash judgment that 3 psi isn't going to make a whit of difference, in fact I doubt that the tolerance from filter-to-filter can even be relied upon to be that good. I guess that if you used a filter designed for a vehicle not even close to the intended application then you could possibly get yourself into trouble, but I find it hard to imagine a problem when using a quality filter that is specified by the filter manufacturer to be correct for your vehicle.

 

Bottom line, that fact that countless owners have been using aftermarket filters for countless miles with no problems whatsoever pretty much answers all the questions one could ask.

 

 

[T__]

Smoky had a good question here. Many who use aftermarket filters, and even some who've had warranty issues, never ask the question of how much oil/minute is pushed through that filter and is that (aftermarket) filter designed to handle that spec? Sure a 'filter' may fit to the bike, but is it able to handle the amount of oil and pressure being sent through it?

I'm not aware of that spec ever being formally measured or published for automotive oil filters, implying (to me) that it's not much of an issue.

 

There is one seldom available rating that I believe is important. The pressure drop at which the internal bypass valve opens signifying a plugged filter. That's the primary reason that I want to know that the filter manufacturer specifies the filter is designed for use on my bike.

 

The number exists and is part of the design specifications, but I don't know whether they vary much from filter to filter. Does anyone know??

 

 

John, I’m not sure that will tell you much or it is even be comparable between filters..

 

There are may other factors involved not just by-pass pressure drop.. Filter media area,, filter media pore size,, engine oil system operating pressure,, oil viscosity,, oil flow to & beyond the filter.. I’m not even sure that some oil filter designs don’t use by-pass pressure drop to maintain a specific operating pressure drop across the filter media..

 

Let’s take a typical engine with 80 psi oil pressure at 80°c,, 40 weight oil at the temperature we are testing at,, fairly loose bearings & lots of things to be oiled under main oil gallery supply-- so a significant flow required though the filter..

Now lets install a filter with a great amount of filter media surface area & lots of fairly large filter media pores & good open folds to allow good oil access & pass through.. Lets assume that filter has a 12 psi by-pass pressure drop..

Now lets take the same engine & oiling system & install a filter with the same 12 psi by-pass pressure drop,, only this filter has very small media pores,, very tight restrictive media folds & 1/5 the media area of the first filter tested..

Both filters would have the same 12 psi by-pass opening but the fist one would probably only see the by-pass operation at cold start or very high rpm’s with not fully heated engine oil while the second filter would more than likely be operating in some by-pass mode most of the time..

BMW seems to have significantly upped the by-pass pressure on the hex head over the oil head.. Is that due to a higher oil demand,, the need to keep the filter out of by-pass operation longer,, possibly a smaller filter with less filter media,, possibly better filter media filtration,, maybe none of the above—maybe that was just the filter that was available in the size & thread they needed from the supplier they used?

 

I’m off work on a long x-mas vacation but when I get back to work after the holidays I am going to have a talk with our lubrication engineering department to see just what the by-pass system is designed to do & if it is in fact used to control working pressure drop across the filter media,, or just for plugged filter protection,, or to allow cold oil by-pass & high RPM high flow by-pass also..

 

I have been in auto engineering for well over 40 years & it seems I still have some learning to do yet on a simple oil filtration system..

 

 

Twisty

 

[smiller]

I’m off work on a long x-mas vacation but when I get back to work after the holidays I am going to have a talk with our lubrication engineering department to see just what the by-pass system is designed to do & if it is in fact used to control working pressure drop across the filter media,, or just for plugged filter protection,, or to allow cold oil by-pass & high RPM high flow by-pass also..

Do let us know. I've never once read of the internal bypass valve being used as anything other than a simple emergency measure to cover for a plugged element or cold oil flow issues, but I'd be interested in what an expert would have to say.

[Joe Frickin' Friday]

The factory service manual for oilheads shows that the cooling oil circuit does not pass through the filter; makes sense, as there's no need to filter out microscopic grit just for a trip through a heat exchanger.

 

So the filtration needs of the oilhead (and presumably also the hexhead) engines are independent of the fact that they are oil-cooled; I would expect the filter flow rate requirement is similar to that of any other engine with similar displacement, whether air, oil, or water-cooled.

[Indy Dave]

Twisty - I love the diagram!! I guess i never took the time to consider how the internals on a boxer differ by necessity from a V or inline engine.