Oil drips, blow-by, What is really the correct oil level?
#1
04-11-2012, 10:35 PM
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Location: Red Banks, Mississippi
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Oil drips, blow-by, What is really the correct oil level?
It seems everyday there is someone asking why they have oil dripping out of their air cleaner.
There is a common misconception on what the proper oil level is on our Harley's. AND it is NOT helped by the confusing verbiage that HD uses in the manual AND on the dipstick.
Running the oil level so that it is halfway between the lower hash mark and the upper hash mark on the dip stick is NOT running the engine low on oil.
IT IS NOT LOW ON OIL UNLESS IT IS AT OR BELOW THE LOWER HASH MARK, at which point oil should be added to bring the oil level to halfway between the two hash marks.
The following is straight from the HD manual, and it is the same for the Twin Cams and the Sportster Evo motors-
"The correct oil level should register midway between the FULL and ADD marks on the dipstick.
If oil level is at or below the ADD mark, add only enough oil to bring the level to the middle of the two marks on the dipstick."
One of the confusing things is that Harley states that the correct (or full) level is "midway between the FULL and ADD marks on the dipstick."
While it is true if it is at or below the ADD mark, then some oil should be added. What is NOT true, is if it is at the FULL mark, it is full. If it is at the Full mark it is OVERFILLED.
Some will point out that the above applies to a cold oil check, and that is correct.
It is also correct that the manual states that you can fill the oil to the top mark on a hot oil check.
IT IS ALSO CORRECT that the manual states that when it is HOT, as long as it is above the lower mark you do NOT need to add any oil at all.
Experience has shown that the ideal level is midway between the two marks, hot or cold.
If you do that, and everything else is functioning properly (umbrella valves, rings, etc.) then you should not have any excessive blow-by causing oil accumulation below your air filter or along the side of the bike.
There is a common misconception on what the proper oil level is on our Harley's. AND it is NOT helped by the confusing verbiage that HD uses in the manual AND on the dipstick.
Running the oil level so that it is halfway between the lower hash mark and the upper hash mark on the dip stick is NOT running the engine low on oil.
IT IS NOT LOW ON OIL UNLESS IT IS AT OR BELOW THE LOWER HASH MARK, at which point oil should be added to bring the oil level to halfway between the two hash marks.
The following is straight from the HD manual, and it is the same for the Twin Cams and the Sportster Evo motors-
"The correct oil level should register midway between the FULL and ADD marks on the dipstick.
If oil level is at or below the ADD mark, add only enough oil to bring the level to the middle of the two marks on the dipstick."
One of the confusing things is that Harley states that the correct (or full) level is "midway between the FULL and ADD marks on the dipstick."
While it is true if it is at or below the ADD mark, then some oil should be added. What is NOT true, is if it is at the FULL mark, it is full. If it is at the Full mark it is OVERFILLED.
Some will point out that the above applies to a cold oil check, and that is correct.
It is also correct that the manual states that you can fill the oil to the top mark on a hot oil check.
IT IS ALSO CORRECT that the manual states that when it is HOT, as long as it is above the lower mark you do NOT need to add any oil at all.
Experience has shown that the ideal level is midway between the two marks, hot or cold.
If you do that, and everything else is functioning properly (umbrella valves, rings, etc.) then you should not have any excessive blow-by causing oil accumulation below your air filter or along the side of the bike.
#2
08-11-2012, 06:46 PM
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Another factor in blow-by that I did not mention above-
Correct viscosity is one that gets ignored a lot. The manual states that the recommended viscosity is SAE 50 if the lowest ambient temps are above 60* and SAE 60 if the lowest ambient temps are above 80*.
However, most people (and Harley Dealerships) are running 20-50 year round, then they wonder why in the middle of summer when temps are 75-100* (like they are in our area) they hear more top end noise and get so much blow-by.
Correct viscosity is one that gets ignored a lot. The manual states that the recommended viscosity is SAE 50 if the lowest ambient temps are above 60* and SAE 60 if the lowest ambient temps are above 80*.
However, most people (and Harley Dealerships) are running 20-50 year round, then they wonder why in the middle of summer when temps are 75-100* (like they are in our area) they hear more top end noise and get so much blow-by.
#3
08-15-2012, 04:40 PM
EVO Blow By
my FXR is the first year EVO, and has a blow by problem,
what would you reccomend....
The compression is 147 both cylinders. a days ride is
a half to a full quart of oil. It seems higher consumption at high
speed, and of course the milage will affect how much.
I'm sure you know, but just to remind the early EVO
was a bottom breather.
what would you reccomend....
The compression is 147 both cylinders. a days ride is
a half to a full quart of oil. It seems higher consumption at high
speed, and of course the milage will affect how much.
I'm sure you know, but just to remind the early EVO
was a bottom breather.
#5
08-15-2012, 06:02 PM
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Location: Red Banks, Mississippi
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The above applies to Twin Cams and Sporty Evo engines. Wish I could tell you off the top of my head what the manual says about proper fill and weight on your Evo big twin.
If you don't have a manual you can look in...maybe someone else does, or I can dig up mine later this week.
If you don't have a manual you can look in...maybe someone else does, or I can dig up mine later this week.
#7
09-08-2012, 12:16 AM
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Location: Red Banks, Mississippi
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Regarding the proper weight oil to run for the temperatures you are riding in.
The following is a copy from an 09 Sportster Manual. The Twin Cam manual says the same thing regarding weight oil.
The following is a copy from an 09 Sportster Manual. The Twin Cam manual says the same thing regarding weight oil.
Last edited by DK Custom; 03-13-2013 at 11:36 AM.
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#8
09-20-2012, 08:48 AM
Elite HDF Member
Got a question. The manual never lists 20W-60 and I've been looking at that weight. I know the 20 is weight when cold (start up) and friction modifiers build the weight to the second number. An air cooled engine gets pretty hot. Right now I do 20W-50 all year round, but I'm thinking I could do 20W-60 (Redline) all year round, and it would be better for my engine and maybe help remove some of the sewing machine sound (top end noise).
#9
03-21-2013, 05:51 PM
Got a question. The manual never lists 20W-60 and I've been looking at that weight. I know the 20 is weight when cold (start up) and friction modifiers build the weight to the second number. An air cooled engine gets pretty hot. Right now I do 20W-50 all year round, but I'm thinking I could do 20W-60 (Redline) all year round, and it would be better for my engine and maybe help remove some of the sewing machine sound (top end noise).
Dealers don't sell diesel oil, so they will always recommend what they sell.
#10
04-04-2013, 10:55 PM
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Here is a link to a thread with more information on the subject-
https://www.hdforums.com/forum/oil-r...f-my-bike.html
https://www.hdforums.com/forum/oil-r...f-my-bike.html