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Oil Breather Alternative

Just out of curiosity, I would like to find out if this oil consumption issue or oil pooled inside the airbox wide spread.

Would also like to find out how often this happens, with our without extended sump?

Is there a relationship with this problem relating to the extended sump?

Reason I ask this, before I installed the extended sump, I found very little oil inside my airbox, after installation of the extended sump, I then had an issue with oil pooled inside my airbox. Was this coincidental, or could there possibly be a connection?

I'm wondering if that oil return system the culprit, and pushing oil into the airbox and thus exasperated by more oil sloshing around in the sump with the extended sump?

I keep noticing people talking about keeping the oil level at the bottom of the dip stick, why would that be an issue anyway, and why would keeping oil or filling to the top of the stick be such an issue? If the sump is acting as a separate oil tank you would think filling to the top dip stick line would be OK....right?

One other possibility......is that the oil return line into the sump was somehow installed too low into that sump by the factory? Thus the blow by past the one way check valve into the airbox. So when that check valve opens and closes oil become trapped on the airbox side and that oil is sucked into the airbox.

Something strange is going on with that oil return system!!!!

The reason I'm wondering about all of this, if you vent to the atmosphere and plug that oil return line, you find out very little oil, just a fine mist blowiiing out from the head vents, not enough to even put much oil into the airbox at all.
 
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I just don't understand the logic (if any) in the design. This is not a Positive Crankcase Ventilation (PCV) system. No fresh air is ever introduced to the system. Everything just connects to the airbox. What little vacuum is there relieves any built up pressure in the crankcase. If fumes are moving from the crankcase up through the valve covers, then oil may be drawn out of the airbox and back into the sump. I'm almost tempted to run the valve cover lines to the intake manifold (T off the eval canister line), but that would put even more oil everywhere (no chance of condensation). Maybe just venting to the air is the best solution. K&N makes little filters just for that purpose. That would stop the mist.
 
I put 2 liters of oil in the crankcase per the book (no extended sump). That's full to the top mark on the dipstick. I've never had to add any oil in 3000 miles. There is oil in the airbox (that's how the breather system works), but little or no pooling. Mine is a V7 II, btw. I don't know if that makes a difference or not. I think the breather system is the same.

In your situation, I would be tempted to replace the check valve in the sump return line. Moto Guzzi doesn't have a lot of luck with check valves.
 
I spoke with small block racer and good friend Sean of RTL Moto yesterday. He showed me the V65TT system and one from the old Eldo that he runs on his current builds, and he says he's never had any oiling blow-by issues or related. I'll link to the items tonight here.
 
I'll combine this thread with the other one of the same topic, but to answer your question, I see handfuls of V7's, and my RentAGuzzi Fleet bikes always have the extended sumps on them for safety insurance. I run them at the add line, and have never had more then a slight visible trace of oil in the bottom of the air box on any of them. Some I service have considerably more, so I think your one of those unlucky ones.
 
The v65 and v65tt work but still pools oil in the air box. Biggest flaw is it fills with water vapour and majo that runs back to the sump.

Poured water out of mine when I dumped it before the v7 lump went in
 
One other thing about all of this. Many companies are having big time issues with the vent systems. I had a major head ach with a couple Evo/twin cam HD's. Nightmare from elm street. I don't know how many times Harley changed those vent systems, for awhile every freakin year they did it some type of other way. My 1979 shovel just vents it out the bottom of the bike, no drama at all. Gheeeeez.

Venting to the bottom of the bike with one of those K&N's will stop that mist, somewhat. I would still route that over to one side clear of the rear wheel tracking. As far to the left as possible without becoming an eye sore.
 
Tod, I think it had something to do with that frocking oil return line, backwards or stuck or something, nevertheless, it's eliminated and vented to the atmosphere, as with the older trouble free venting systems the old bikes always had.

This thing gave me fits losing oil at an alarming rate and fouling out my plugs in the process. The bike ran great and better yesterday once I by pass all of this stupid crap. Sure is nice to have a nice clean airbox for once with plugs that actually are not all fouled up with oil.

This bike is driving me nuts.

If you visit Italy, keep that bar of soap on a rope.
 
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End up running it to the back fender with a T into one line inside the rear fender. That other experiment out the bottom of the bike just made a mess with the oil mist after a good long ride today. I'm hoping it vents well enough with the two lines going into the T and then into one line. I had an oil film all over the kick stand and center stand after that run today with it vented out the bottom of the bike, what a mess. Looked at some oil trap cans on line but think that will look bad, can't figure out a good place to hide one of those things.

I hope this line out the back is the final final on this thing, I'm about burned out on this venting issue.

Just hope I don't dream about this chit in bed tonight...gheeeez.
 
Surprised that in all of this discussion no one has mentioned part # AP8104525 "Filter blow-by"? These are two pieces that go in the cam-head oil mist separator sections of the Air filter box. I'm not sure at this point if they are meant to be cleanable or disposable, perhaps somewhere along the line on your bikes the air filter was changed and these blow-by filters were just tossed? They cost about $2.60 each.
 
Daniel Swords said:
Surprised that in all of this discussion no one has mentioned part # AP8104525 "Filter blow-by"? These are two pieces that go in the cam-head oil mist separator sections of the Air filter box. I'm not sure at this point if they are meant to be cleanable or disposable, perhaps somewhere along the line on your bikes the air filter was changed and these blow-by filters were just tossed? They cost about $2.60 each.
Click to expand...
It has been brought up in this thread believe. I don't think this is the issue.

It seems this issue has been resolved decades ago per below, but likely not environmentally friendly since it vents to the atmosphere. As stated above, small block Racer Sean adapted this system to his race bikes and said never a drop in the vent to air line (and into a catch can in his case).
Iain, the V65TT vent system he showed me was very different then you describe. His system did not vent to the air box.
The system shown below would use the stock return line to the bottom of the pan, and you'd have to add just one line for atmospheric vent in a location of your choice.

This is the older $40 vent box (click for info);

Vent line from valve covers to box above for $30:
 
Looks like a good clean system as far as oil misting goes. I'll keep that in mind.

How big is that little tank? Will it fit in between the jugs?
 
GuzziV65TT said:
The v65 and v65tt work but still pools oil in the air box. Biggest flaw is it fills with water vapour and majo that runs back to the sump.

Poured water out of mine when I dumped it before the v7 lump went in
Click to expand...

Good point about that water vapor. That is getting back into the sump and going into the combustion chamber. I'm concern about that water vapor collective properties in the motor oil, especially with cooler starts that water is getting to those bearings and every other moving part that depends on being lube by clean uncontaminated oil.

Not so much an issue during summer months, but during winter riding that could cause damage to the hard coats on the main bearings.

I once had a transmission go to crap on an older Triumph Bonneville caused by contaminated oil that never got hot enough during the winter to burn off the water. Corroded the freakin gears and then they lost that hard coat. Had to rebuild everything inside that transmission. The bike had spent a great deal of time on the north coast, which can cause issues with mayo during the winter. In the Valley it's not so much of an issue.

After that I always made sure to do a good long run to get those temps up inside of that transmission, then checked often for mayo. Not really an issue in California during the summer months.
 
V65 and tt oil breather is a chunky square plastic unit that sits in front of the coils , had a dual connection to it from the valve covers , at the bottom a return to the rear of the sump and on top a corrugated hose that connect to the top of the large square v65 airbox
 
So MG decided to route the oil return line through the airbox. Makes no sense to me at all. Using the frame to condense the oil is OK, though. It sounds like we could take the oil return line that comes from the lowest point in the frame and connect it directly to the sump. Plug the two holes in the airbox and we essentially have what is described above.

This is the current "oil breather":
J0cEul.jpg


The top tube of the frame collects the fumes from the valve covers in the center of the picture. Air is drawn into the airbox from the higher fitting on the left. On the bottom of the tube on the right in the picture is the oil return line. I would think simply connecting that line directly to the sump would keep most of the oil out of the airbox and the bike would still be emissions compliant. What say you?
 
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Pokey, Good observation on your part about by-passing that air box with the return of that oil into the sump. I would be concern with returning mayo along with it into that sump? What say you?

By the way, I went totally outlaw venting to the rear fender. Sump return plug along with all 4 holes in the box plugged. I'm no longer a 4 holler.

Rick, former 4 holler, no more hole.
 
Pokey, plug that oil return line to the sump and let the frame fill with oil. I think it would really be kewl to see how long it takes to fill the frame with oil. You could even end up never ever buying oil again,Just keep recycling it.
 
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