Lube Oil Burn Rate

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captrigney

Senior Member
Joined
Sep 22, 2012
Messages
177
Location
USA
Vessel Name
Meander
Vessel Make
1983 Grand Banks 36 Classic
What would you expect for a "normal" burn rate for lube oil for a FL 120? I'm aware that there are many variables involved. If perhaps there is no "normal", what do you burn?

John
 
What would you expect for a "normal" burn rate for lube oil for a FL 120? I'm aware that there are many variables involved. If perhaps there is no "normal", what do you burn?

John

I'm also curious to what American Diesel has to say...anyone ask them?

Till I learned not to use the "full" mark on my dipstick...I burned between 1/2 and one full quart every 10 hours or so. Now after learning that...I think I only burned a gallon in almost 300 hours of my last trip. That is on a less than 1000 hr, rebuilt engine. I did an oil change at the 150 mark or so, maybe 2 qts between the oil change.
 
Ditto on the full mark. Mine leaks (via the rear main seal I think) if I fill to the full mark. If I keep it at "min" it uses maybe a quart every 50 or 60 hours something like that, but it all depends on my running rpm. If I'm running 1700 or less (normal for me) it uses almost nothing. If I run at 1800 or 1900 for very long it uses more.
I read somewhere a long time ago that burning up to 1% of your fuel use is ok.Anyone else have an opinion on that percentage?
 
I was reading something about the angle that the motor sits on it's mounts will change the marks on a dipstick.

My dip stick has homemade marks on it it was calculated by that angle.

If the angle is not compensated for it can cause the motor to slobber oil

sd
 
Ditto on the full mark. Mine leaks (via the rear main seal I think) if I fill to the full mark. If I keep it at "min" it uses maybe a quart every 50 or 60 hours something like that, but it all depends on my running rpm. If I'm running 1700 or less (normal for me) it uses almost nothing. If I run at 1800 or 1900 for very long it uses more.
I read somewhere a long time ago that burning up to 1% of your fuel use is ok.Anyone else have an opinion on that percentage?

I haven't heard the 1% rate but sounds reasonable...I know that's how Cat started determining overhaul a few years back on some engines...when your oil consumption rate doubles for the same fuel burn...and I'm pretty sure it's not from the original oil consumption
rate but something reasonable down the line.
 
I run at around 1500-1600 rpm. Engines have just over 2000 hours, they use very little of 15-40 multigrade oil. I don`t always top up between changes.
 
Thanks for the replies. I haven't been burning any oil (running 1.5-1.7k) and was concerned maybe some fuel was making it's way to the crankcase to replace any lube that I was burning. Not to worry for now.

John
 
I replace the engine oil once a year, averaging 125 hours annually of engine usage. There has been no need to add oil between changes. But that's for a JD4045.
 
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I had a JD 4045 as a generator that we used all the time on a tour boat. 250 hours between changes running 1800 rpm and not only did we not add oil, the oil on the dipstick was still golden brown, not black.
 
>Thanks for the replies. I haven't been burning any oil (running 1.5-1.7k) and was concerned maybe some fuel was making it's way to the crankcase to replace any lube that I was burning. Not to worry for now.<

Good question , as every engine will use some oil,the only way to actually know is oil testing.

This should be done every oil change , you will easily be able to see if fuel is making up for the oil consumption.

Some oil has to be left on the cylinder walls every stroke , so there must be oil consumption.
 
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...was concerned maybe some fuel was making it's way to the crankcase to replace any lube that I was burning.

Look up blotter test of lube oil. You put a drop of oil on a business card or other absorbent paper and perform your own chromatographic analysis.

It is a remarkably accurate gauge of oil condition and quickly shows if you have fuel contamination.
 
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