Oily exhaust tailpipe, ok? Too much?

[usedtobefast]

Bike is a 2000 Quota 1100ES with almost 24,000 miles.

I noticed the rear exit of the exhaust was very black ... so cleaned it up and it was like grease in there, not dry sooty.

So I got it spotless clean, rode it ~300 miles, did another tail pipe wipe, and it seems like grease consistency, guessing it is "burnt" oil?

pic:




So is this too much for 300 miles of use?  Is it a safe guess it is the valve guides leaking oil? 

Airbox is clean, no oil in there from crankcase blowby.  (Was hoping that was happening and then running thru the motor)

Hopefully not piston rings at 24K miles.

Suggested troubleshooting steps?  Or keep an eye on the oil level and ride it and don't worry?   

[lucky phil]

Bike is a 2000 Quota 1100ES with almost 24,000 miles.

I noticed the rear exit of the exhaust was very black ... so cleaned it up and it was like grease in there, not dry sooty.

So I got it spotless clean, rode it ~300 miles, did another tail pipe wipe, and it seems like grease consistency, guessing it is "burnt" oil?

pic:




So is this too much for 300 miles of use?  Is it a safe guess it is the valve guides leaking oil? 

Airbox is clean, no oil in there from crankcase blowby.  (Was hoping that was happening and then running thru the motor)

Hopefully not piston rings at 24K miles.

Suggested troubleshooting steps?  Or keep an eye on the oil level and ride it and don't worry?   

My suggestion is if the bike is running well and not consuming excessive oil or smoking you stop looking at exhaust tips. Sharing a garage at track days with 3 other bikes, all big Ducatis you end up with oil spatters all over the fairing from the bike in front of you 4 feet away starting up with a rich mixture from cold and a little cylinder wash and maybe some guide leakage. Doesn't mean they have an issue and the effect is transient starting from cold and warming up.
You cant tell anything from exhaust tips these days esp on old technology engines running Unleaded fuel. You know that grey look to exhaust tips you remember seeing years ago? That was lead in the fuel. Unleaded fuel will always produce a black look to the tips for a road engine because they spend a fair bit of time on the cold rich fuel trim. A race engine running unleaded fuel will have totally clean exhaust tips because they spend little time on the enrichment map and operated at or around peak torque and above for 95% of there running life.
A race engine running on leaded fuel will generally have grey exhaust tips. Forget about reading the tips on a road engine though as I said. It's like reading plugs on a road engine, too much low speed cold start running to be of much use. That's why racers had to do plug chops in the old days because a cool down lap back to the box obscured any info useful info off the plug.   

Ciao 

[GeorgiaGuzzi]

What Phil said. The black oily soot like substance is present on my Quota too, and my victory. Also Suzuki I had as well as the kz1100. 😂😂😂

[John A]

It’s an internal combustion engine, very few are perfect and even then they will leak and smell. How much is too much is often down to personal preference as long as it’s not displaying signs of failure or using too much oil or gas. We used to paint the inside of the exhaust white to fool with our friends back in the days when gas was leaded. Can you fix it? Sure if you want to do a top end rebuild early, otherwise my advice is quit lugging it. Some things you have to “let it develop “

[usedtobefast]

OK, thanks for replies.

For me this is the first 4 cycle engine that had a oily tail pipe.  I've seen black dry sooty stuff before.

My Racer pipes are clean inside as is the Griso (and my KTM 450 offroad bike with 5000 miles on it).

On the Quota, after an oil change it was 1/2 way between Max/Min, after 2000 miles it went down to 1/4 way between Max/Min, that seems reasonable to me. 

It runs great and I'm getting 34-38 mpg, which seems about right for a Quota.

[usedtobefast]

... my advice is quit lugging it.

How would lugging make it burn more oil?  Does that make leaking valve guides leak more? 

I don't lug it in a bad way, like in 5th going 30 mph and twist on the throttle ... I don't do that. 

But I also don't spin the heck out of it.  On mountain uphill roads, then maybe 4000-6000 rpms.  On flats then maybe 3500-5000 rpms.   Like rev up to 5k, shift, rev up to 5k, shift.  If riding along in traffic on a 45mph road, maybe running around 4k, maybe 3,800, maybe 4,500, something like that. 

[John A]

How would lugging make it burn more oil?  Does that make leaking valve guides leak more? 

I don't lug it in a bad way, like in 5th going 30 mph and twist on the throttle ... I don't do that. 

But I also don't spin the heck out of it.  On mountain uphill roads, then maybe 4000-6000 rpms.  On flats then maybe 3500-5000 rpms.   Like rev up to 5k, shift, rev up to 5k, shift.  If riding along in traffic on a 45mph road, maybe running around 4k, maybe 3,800, maybe 4,500, something like that.

sound about right, it was just generic advise . I try to keep them 4k and above if there is any load. I was wondering if the breather system on those are not quite up to the task. that could cause it..

[GeorgiaGuzzi]

I wonder if the spark plugs are too “hot”, keeping the cylinder from reaching its optimum operating range. Remember “hot” vs “cold” in spark plugs is opposite from what it sounds like.

[lucky phil]

I wonder if the spark plugs are too “hot”, keeping the cylinder from reaching its optimum operating range. Remember “hot” vs “cold” in spark plugs is opposite from what it sounds like.

Spark plug heat range has no effect on "cylinder optimum operating range" by which I assume you mean optimal combustion efficiency, unless it's wrong by a mile. So way to "hot" it would be detonation/pre ignition and way too cold would be plug fowling and misfiring. If its running nicely the plugs wont be a factor. in what the OP is talking about.
Its a 20 year old air cooled Italian pushrod twin, you cant look too hard at the minutia. 

Ciao

[GeorgiaGuzzi]

Spark plug heat range has no effect on "cylinder optimum operating range" by which I assume you mean optimal combustion efficiency, unless it's wrong by a mile. So way to "hot" it would be detonation/pre ignition and way too cold would be plug fowling and misfiring. If its running nicely the plugs wont be a factor. in what the OP is talking about.
Its a 20 year old air cooled Italian pushrod twin, you cant look too hard at the minutia. 

Ciao

Not to be argumentative at all, I was just trying to think of why it would be “oily”. Remember the 2nd function of a spark plug is to remove heat from the cylinder and transfer it to the head. This is important in highly modified, high compression motors. Some people, not the OP, think “it’s an Italian motorcycle, it’s high performance“ and do silly things like run a plug that is too cold and end up cooling combustion chamber too much, which can foul plugs and lead to an oily exhaust. I personally don’t see anything wrong with the soot his bike has, especially if it has a mistral y pipe like mine. That’s all, just throwing around w.a.g.’s! 😉

[lucky phil]

Not to be argumentative at all, I was just trying to think of why it would be “oily”. Remember the 2nd function of a spark plug is to remove heat from the cylinder and transfer it to the head. This is important in highly modified, high compression motors. Some people, not the OP, think “it’s an Italian motorcycle, it’s high performance“ and do silly things like run a plug that is too cold and end up cooling combustion chamber too much, which can foul plugs and lead to an oily exhaust. I personally don’t see anything wrong with the soot his bike has, especially if it has a mistral y pipe like mine. That’s all, just throwing around w.a.g.’s! 😉

No arguments here just discussion. The heat range of the plug has more to do with the plugs ability to cope with the heat produced by the engine. The plug itself offers no real cooling per say to the combustion chamber. So a high performance engine that has high cylinder pressures and BMEP and is operated at or near it's operating threshold and producing a lot of heat needs a cold plug. The term "cold plug" relates to the plugs ability to shed heat its subjected to so it stays withing it's own safe operating parameters. It's not about its ability to assist engine cooling. Conversely a "hot" plug is designed to run at a higher temp itself in lower performance engines to keep itself clean and prevent carbon build up and fowling.
Although not related to a Guzzi modern DFI engines now have another ignition related event to contend with LSPI ( low speed pre ignition) which destroys Turbocharged engines in particular at wide throttle openings at less than the upper rev ranges. So not WOT a low revs more high throttle openings at revs below around 2/3 of maximum. Its related to oil contamination in the combustion chamber and the reason you will now be seeing oils labelled SN "plus" to help combat this. LSPI happens when your not giving the engine a particularly hard time which catches a lot of people out.

Ciao

[usedtobefast]

So I looked though some of my notes ... so the Quota is using 1 litre of oil in 1500 miles ... that sounds excessive to me.  I'm just taking short day rides of 40-120 miles, no long hot 80 mph interstate stuff ... most is 30mph-60mph curvy backroads in not so hot weather ... seems like that would be easy on an engine.

I keep the oil level at mid mark on the stick ... so level goes down, I add 300cc to get back to mid mark again, not filling to full level.  Also airbox is clean inside and oil free so not getting a bunch dumped in from crankcase vent. 

So ... keep pouring in oil and don't worry about it?      Or pull heads off and send them to Harpers?   And mileage is just under 24,000 miles. 

Also, when starting, I don't see any smoke coming out.  Start, warm up, clear exhaust.

I would certainly hope at that mileage that piston/rings/cylinder is all OK and any excessive oil use is valve guides.

[lucky phil]

So I looked though some of my notes ... so the Quota is using 1 litre of oil in 1500 miles ... that sounds excessive to me.  I'm just taking short day rides of 40-120 miles, no long hot 80 mph interstate stuff ... most is 30mph-60mph curvy backroads in not so hot weather ... seems like that would be easy on an engine.

I keep the oil level at mid mark on the stick ... so level goes down, I add 300cc to get back to mid mark again, not filling to full level.  Also airbox is clean inside and oil free so not getting a bunch dumped in from crankcase vent. 

So ... keep pouring in oil and don't worry about it?      Or pull heads off and send them to Harpers?   And mileage is just under 24,000 miles. 

Also, when starting, I don't see any smoke coming out.  Start, warm up, clear exhaust.

I would certainly hope at that mileage that piston/rings/cylinder is all OK and any excessive oil use is valve guides.

Well Personally I don't think that's excessive. It's more than most would like but lets face it most would like to be able to say zero oil consumption. Remember not only are the riding conditions a factor but so is the cycles. Most of the consumption will be during the warm-up period so you may well do country riding but there's a big difference between 3000klm of country riding with an average of say 80klm/ride which would be 38 start cycles in 3000klm of riding compared with an average ride distance of 400klms in 3000 which is 8 start cycles.
The cold starts with increased clearances and rich mixture and cylinder washing is where the oil consumption probably is. The other factor is how hard the engine is loaded. Nothing like some dyno time with 8-10 hard WOT pulls to clean out the cobwebs and work the ring sealing.
Twice touring around Europe in the mis 80's on brand new BMW K100RS's they used around the figure of your bike which never worried me but was a little inconvenient for someone that likes to stick with the same oil for top ups.   

Ciao
 

[Chuck in Indiana]

Just assuming it's valve guides isn't the best method of trouble shooting.  If I were concerned, I would do a leak down and find out where the engine is leaking. I wouldn't like an engine burning a quart in 1500 miles, but it's not really all that bad. <shrug>

[lucky phil]

Just assuming it's valve guides isn't the best method of trouble shooting.  If I were concerned, I would do a leak down and find out where the engine is leaking. I wouldn't like an engine burning a quart in 1500 miles, but it's not really all that bad. <shrug>

I'll bet every piston engine in every aircraft you've ever owned has burnt way more oil than that on a per hour basis Chuck
I still think chasing oil consumption on something like a Guzzi thats used on short rides may be a little tough. I personally would check the level then do a couple of 500 klm rides before I got too concerned. I mean as pete Roper points out its only an old ditch pump after all

Ciao

[usedtobefast]

Just assuming it's valve guides isn't the best method of trouble shooting.  If I were concerned, I would do a leak down and find out where the engine is leaking. I wouldn't like an engine burning a quart in 1500 miles, but it's not really all that bad. <shrug>

I don't have a leak down tester or an air compressor ... is there a tester that does not require an air compressor?  I did some googling and seems they all are designed to work with an air compressor (vs. cheap guy hand pump). 

And that would tell me if it is leaking around rings/piston and/or valve seats ... but if the valve seats and valves are good, but the guides/seals are bad, I guess the leak down doesn't really show that?

thanks

[Don G]

If your guides are worn the valve seating will be out to lunch, and your leak down will indicate this.  DonG

[Wayne Orwig]

Is one plug wetter than the other?

I have never really had a Guzzi motor noticeably burn oil in 300,000 miles of riding them. Of course I have had them blow oil into the air box when they are over filled. But to me, if you truly have a motor issue, it is unlikely to be all four valve guides, and is more likely to be a single point. So it should show up on one plug versus the other.

Is there a chance that your crankcase vent system is plugged and the crank pressure to excessive? You said the airbox is clean. Pretty rare.

What weight oil are you using?

[usedtobefast]

Is one plug wetter than the other?

I have never really had a Guzzi motor noticeably burn oil in 300,000 miles of riding them. Of course I have had them blow oil into the air box when they are over filled. But to me, if you truly have a motor issue, it is unlikely to be all four valve guides, and is more likely to be a single point. So it should show up on one plug versus the other.

Is there a chance that your crankcase vent system is plugged and the crank pressure to excessive? You said the airbox is clean. Pretty rare.

What weight oil are you using?

The plugs aren't so "wet" as they are "encrusted with black stuff" ... the left one much worse than right one.   Like after 600 miles I have to scrape or sand the crusty black stuff off ... not oily like it can be wiped off with a rag.

I have looked at the crankcase vent ... it was clean and the ball in there was free to move around, but I didn't really know how to test it.  I did look inside the airbox because my first thoughts were it was spitting oil up into the airbox and then burning it thru the engine that way ... but the airbox was dry, no oil inside there.

Oil is Maxima 20W50 high performance mineral oil.

[usedtobefast]

I do have a compression gauge (got it for my dirt bikes a while back).

On a dirt bike, single cylinder and carb, I get it warmed up, pull plug, put in gauge, hold throttle wide open, kick several times, look at compression reading. 

How do I do this on my Quota?
Still get bike warm I would expect.
Pull both plugs
Have both plugs in caps and grounded against engine?
Hold throttle wide open during test?  Or not needed?  Bad idea with FI?

At least that should give me some idea of engine health? 

[Rough Edge racing]

 Compression and leak down are useful but they can can't tell you the condition of the  oil scrapper rings...or the valve guide wear unless its so bad the valve doesn't  seal. But you can assume if compression is low or air is blowing past the rings then there is a problem.

[lucky phil]

The plugs aren't so "wet" as they are "encrusted with black stuff" ... the left one much worse than right one.   Like after 600 miles I have to scrape or sand the crusty black stuff off ... not oily like it can be wiped off with a rag.

I have looked at the crankcase vent ... it was clean and the ball in there was free to move around, but I didn't really know how to test it.  I did look inside the airbox because my first thoughts were it was spitting oil up into the airbox and then burning it thru the engine that way ... but the airbox was dry, no oil inside there.

Oil is Maxima 20W50 high performance mineral oil.

So new/further information, a degree of plug fowling as well. So Is the fowled plug the same side as the oily pipe or the predominantly oily pipe? If you can pull the header pipes and throttle bodies off ( T/B's I know extremely hard) and compare what you see on the back of the valves you can usually see the evidence of leaking guides by the build up, sometimes even oil itself. Remember a 2 valve Guzzi only relies on a guide scraper not a proper seal like most engines designed in the last 75 years.

Ciao   

[usedtobefast]

Ok, first step, just ordered 8 quarts of oil!  So I can get my fall riding in.   

Next, I'll do a compression check.  What the heck, I have the gauge and that'll be some extra info.

On the Quota, exhaust is 2 into 1 ... so I can't compare tail pipe oil for right & left sides.

I think it isn't too hard to take the intake tracks off ... then I could peak in at the intake valves ... think I'll do that if it does seem to hard.   

Also might start asking around to see if anyone I know can do a leak down test. 

Thanks for the ideas/suggestions.

[lucky phil]

Ok, first step, just ordered 8 quarts of oil!  So I can get my fall riding in.   

Next, I'll do a compression check.  What the heck, I have the gauge and that'll be some extra info.

On the Quota, exhaust is 2 into 1 ... so I can't compare tail pipe oil for right & left sides.

I think it isn't too hard to take the intake tracks off ... then I could peak in at the intake valves ... think I'll do that if it does seem to hard.   

Also might start asking around to see if anyone I know can do a leak down test. 

Thanks for the ideas/suggestions.

I don't think the comp or leakdown will be of much use. If it was putting oil in the airbox then sure but it will be interesting to see what the figures are anyway. If you go down the path of pulling the heads and or barrels then the T/B's will need to come off anyway and a peak down the inlets might mean you can see which is the more likely head if it is a guide leak. Pulling the header pipes is easy so that may also tell you if you have a leaking exhaust valve guide without to much hassle.
 
Ciao

[Wayne Orwig]

Next, I'll do a compression check.  What the heck, I have the gauge and that'll be some extra info.

The compression test will likely give you more info to worry about, but no good answer. 

[lucky phil]

Ok, first step, just ordered 8 quarts of oil!  So I can get my fall riding in.   

Next, I'll do a compression check.  What the heck, I have the gauge and that'll be some extra info.

On the Quota, exhaust is 2 into 1 ... so I can't compare tail pipe oil for right & left sides.

I think it isn't too hard to take the intake tracks off ... then I could peak in at the intake valves ... think I'll do that if it does seem to hard.   

Also might start asking around to see if anyone I know can do a leak down test. 

Thanks for the ideas/suggestions.

Another reason to pull the headers is to see which looks the "oiliest" internally.

Ciao 

[usedtobefast]

Did compression check, 155 psi both right and left side.  To me, seemed like that was great news.

(Bike warm, throttle wide open, both spark plugs out of bike but in caps and plugs wedged against engine case so they could happily spark )

So I'm still in the "valve guide" frame of mind.

Bike is not leaking oil.  Crankcase vent is not dumping into airbox.  155 psi seems like good (great?) piston/ring/cylinder condition.  So it is valve guides or what else?? 

I'm in the San Francisco bay area ... was thinking of taking the heads off and sending to Harpers and have them go thru everything ... I want a Moto Guzzi expert to go thru it vs. just a motor guy.  I do have Ted Porter 20 minutes away (excellent BMW guy), I know he does some Guzzi stuff and he is an expert on BMW airheads, but again, not Guzzi focused. 

Any suggestions for places to do this? 

Thanks

[GeorgiaGuzzi]

Morning! Just wanted to give you an update now that I’ve put almost 1,500 miles on my Quota. It hasn’t burned any oil. (I know I’m tempting fate typing that!) Plugs look good. Just rolled over 49k. Inside of exhaust is still nasty, but I’m thinking maybe what I’m calling oily and what you have are orders of magnitude different.

As far as guides go, my suggestion is to get a friend to follow you on a ride and pay close attention for light blue smoke. It dissipates quickly and is hard to see in mirrors until it’s really bad. Or set up a GoPro looking backwards mounted to the right pannier mount.

Is there large enough difference between Guzzi valves and Beemer valves not to use a known mechanic? Not trying to be smart, I honestly don’t know myself.

[usedtobefast]

Seems to me any shop that is familiar with BMW air head bikes would find the Moto Guzzi very similar.  But, the 2 local places I have called (BMW experts) say they only work on BMWs. 

I checked with Harpers and they do this kind of work ... so if I decide to pull the heads off I think I'll just send them to Harpers ... that way they'll have the parts as they inspect stuff.

I'm more familiar with bikes that have valve guide seals ... and those are pretty easy to change out ... but looking at parts diagrams, it seems like this engine has no seals?  So just the metal valve stem inside the metal valve guide prevents oil from running down the valve stem? 

I was thinking of waiting for the rain season here in California ... but seems we are in the "bad air quality" season, so getting a bit tempted to pull the heads off now.   

I know guys are saying just ride it as is, and I could do that if it was more like 1 qt every 3000 miles ... but 1 qt every 1500 miles is hard for me to just leave it like that.   This Quota is now under my stewardship and I should take care of it properly.   

[lucky phil]

Seems to me any shop that is familiar with BMW air head bikes would find the Moto Guzzi very similar.  But, the 2 local places I have called (BMW experts) say they only work on BMWs. 

I checked with Harpers and they do this kind of work ... so if I decide to pull the heads off I think I'll just send them to Harpers ... that way they'll have the parts as they inspect stuff.

I'm more familiar with bikes that have valve guide seals ... and those are pretty easy to change out ... but looking at parts diagrams, it seems like this engine has no seals?  So just the metal valve stem inside the metal valve guide prevents oil from running down the valve stem? 

I was thinking of waiting for the rain season here in California ... but seems we are in the "bad air quality" season, so getting a bit tempted to pull the heads off now.   

I know guys are saying just ride it as is, and I could do that if it was more like 1 qt every 3000 miles ... but 1 qt every 1500 miles is hard for me to just leave it like that.   This Quota is now under my stewardship and I should take care of it properly.   

2 valve BB Guzzi's dont use guide seals, they rely on a knife edge scraper formed as part of the guide at the rocker end. Why? who knows, probably inertia in the design department.

Ciao