Drinking oil .
Drinking oil .
My 04 Roadster with 25,000 miles on it is drinking oil . I'm using a litre ( Quart ) every 800 - 1000 miles or so . The plugs are brownish black with little white deposits which is the usual indication that the oil is being burned . Before I start compression testing and considering pulling the cylinders , does anyone think it might be my choice of oil itself that could be the issue here ? I'm using Silkolene V Twin and I can't recall having this issue before I made the switch . An experienced mechanic and Harley specialist whose opinion I respect has suggested that my Umbrella valves might be malfunctioning and that positive crankcase pressure may be at work here . I guess I'm just considering the simplest solutions first before I commit to a tear down . I can do the work but I'm just a little disappointed . I was rather hoping to just ride my Harley and concentrate on my other projects .
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From: San Diego, CA
I've got a rear lower rocker box gasket spritzing oil, so going with the Cometic kit and changing it out, as well as the umbrella valve. I guess after 30 years I can't be surprised. That seems like a lot of oil loss, hope you find the culprit. It took a while for me to identify my oil leak, but as it got worse, it became very obvious. I was suspicious of the umbrella valves until I actually saw oil spitting out of the gasket.
John
John
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From: England
I hope you find the problem - doing more than an oil change worth of top ups seems pretty serious to me.
If all that oil is going through the combustion chambers I would expect a healthy cloud of smoke is following you.
If all that oil is going through the combustion chambers I would expect a healthy cloud of smoke is following you.
I think you might be thinking of the primary oil . 1 litre in the engine oil tank is from just touching the bottom of the dipstick to the top of the dipstick when measured hot . Harley Davidson actually state that 1 litre per 1000 miles is " Acceptable " There is no smoke whatsoever nor are there any leaks . Just white deposits on blackish plugs .
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From: Honah Lee
Why are you concerning yourself with less then $10 extra per 1000 miles. Your old girl will probably put on another 25K with no problem and I seriously doubt it will be any different then. What and how you describe plugs is fine.
You need to update your user to your year, model and all the letters. A FI bike will read plugs different then a carb bike. Also, cylinders will last a lot longer on a stock FI without a silly tuner. My 04 has 50K and has the same compression as it did when I first checked it back at around 25K. It also does not have any trouble with valve seals.
How you drive a engine has a lot to do with oil consumption. I don't use engine much for breaking. I just ride it down as long as I don't have some idiot behind me, Right before stopping, I clutch and come to low. Makes a big difference. Throttle closed and engine breaking creates a big vacuum that pulls oil in. Little a a time. Hurts nothing and probably for most safest if you don't like keeping an one eye looking fwd while the other does the constant 360.
You need to update your user to your year, model and all the letters. A FI bike will read plugs different then a carb bike. Also, cylinders will last a lot longer on a stock FI without a silly tuner. My 04 has 50K and has the same compression as it did when I first checked it back at around 25K. It also does not have any trouble with valve seals.
How you drive a engine has a lot to do with oil consumption. I don't use engine much for breaking. I just ride it down as long as I don't have some idiot behind me, Right before stopping, I clutch and come to low. Makes a big difference. Throttle closed and engine breaking creates a big vacuum that pulls oil in. Little a a time. Hurts nothing and probably for most safest if you don't like keeping an one eye looking fwd while the other does the constant 360.
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From: England
I think you might be thinking of the primary oil . 1 litre in the engine oil tank is from just touching the bottom of the dipstick to the top of the dipstick when measured hot . Harley Davidson actually state that 1 litre per 1000 miles is " Acceptable " There is no smoke whatsoever nor are there any leaks . Just white deposits on blackish plugs .
Although my 2017 engine has only covered 13000 miles it uses just a tiny bit of oil and my partners 2008 Custom with 16k on the clock is the same. You are right to want to find out where the oil is going.
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The engine takes around 3 litres at the oil change interval of 5000 miles. If you put in 1 litre / 1000 miles I reckon you have done an oil change during the interval, yes?
Although my 2017 engine has only covered 13000 miles it uses just a tiny bit of oil and my partners 2008 Custom with 16k on the clock is the same. You are right to want to find out where the oil is going.
Although my 2017 engine has only covered 13000 miles it uses just a tiny bit of oil and my partners 2008 Custom with 16k on the clock is the same. You are right to want to find out where the oil is going.
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From: Reston, Va
And that doesn't even begin to address what happens with the oil filter...
We had to work out a problem in Differential Equations similar to this. What if you had a tank full of brine and then had in inflow of fresh water with an equal outflow. How long would it take for the inflow to reduce the salinity of the tank to 50%? To 25%? To 0%? Guess what. No matter how much fresh water you add to the system, you never get to 0%, unless you let the system run for an infinite amount of time.
As for the OP's issue, I really don't have anything to add except that "losing" that amount of oil doesn't sound good to me, especially if you can't tell whether you're burning it or leaking it. I had a truck that died a horrible death because of an oil issue. It had a dry sump when the crank bearings gave out. The engine warning lights never came on. There was no evidence in or around the tail pipe -- the telltale black smudges that should be there -- when I got the truck off of the road. The top and bottom exterior of the engine as well as the undercarriage of the truck was clean. The only thing I can figure out is that the oil sensors are on the top end of the engine, and that all of the oil had been pumped into the top end but the drain to the bottom was clogged so none got back down the sump and the crankshaft.
Anyway, sorry to read about the oil issue. I apologize for the math lecture and for the melancholy remembrances of about the truck. Good luck with your ride. I hope you get it figured out soon.