Purging the old oil
Seasoned HDF Member
Joined: Nov 2009
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From: Farmington ,MS
Put one drop of blue food coloring in a glass of water, and the whole glass turns blue
Novice
Joined: Jun 2018
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From: England
Run it for 50 miles then check dip stick. Wipe off then dip the dipstick in a clean bottle of oil, you will see a big difference.
Dirt don't hurt
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From: Haslet Texas
Man I don't know what is wrong with your motor but if you are getting significant coloring after only 50 miles something ain't right in your motor.
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From: Sandy Eggo's North County
The oil that remains in an engine after draining is called "clingage." It is on every surface that the oil comes in contact with. Case surfaces, bearing and race surfaces, shafts, flywheels, any and all surfaces that come in contact with the oil.
Different engines hold different amounts. (BBC's hold over a quart, for instance.)
Based on the physical size of our engines, I'd guess that there is less than 2 cups remaning, on a properly drained HD engine. This includes leaning the engine both ways to get the best drain. I do this on every drain as it seems to remove add'l oil.
Different engines hold different amounts. (BBC's hold over a quart, for instance.)
Based on the physical size of our engines, I'd guess that there is less than 2 cups remaning, on a properly drained HD engine. This includes leaning the engine both ways to get the best drain. I do this on every drain as it seems to remove add'l oil.
Cruiser
Joined: Jul 2023
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From: California
111k. Top end rebuild at 92k. Cases have never been split and still ruining strong. Use Conventional Oil and have NEVER purged oil. Not bashing anyone who wants to do it as I am sure I do lots of stuff that others think is nonsense but if you change your oil when your suppose to you will never have an oil related problem.
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From: Michigan 15 Minutes East Of Hell
Cruiser
Joined: Jul 2023
Posts: 143
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From: California
If you have a liter of oil in your engine after you drain it...you are not doing it correctly.
Many Harleys have the kickstand on the opposite side from the drain...so if you drain it on the kickstand, you will leave a lot of oil in the tank...you have to lean it over to get it all out.
A properly drained engine will only have a couple of ozs left in it .
Many Harleys have the kickstand on the opposite side from the drain...so if you drain it on the kickstand, you will leave a lot of oil in the tank...you have to lean it over to get it all out.
A properly drained engine will only have a couple of ozs left in it .
Cruiser
Joined: Jul 2023
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From: California
FWIW ... https://roguechopper.com/
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From: Honah Lee
Would be easier to remove the return line to tank, after a oil change to do this, actually thinking about doing this to my bike, since it hasn't ran in awhile. Added two quarts to it, and rode it yesterday, oil level remained the same so there wasn't but a quart of oil in the bike. Also checked when hot, and level, and ran on jiffy stand with dipstick out seems there is a flow with bubbles in tank.
Unlike car motors that the oil in the pan is protected from a spinning crank so oil is not whipped up, what you see on a Harley is the returned scavenged oil.
It's going to be bubbly on top.
Pick up in the bottom of bag is relatively not so bubbly going back to pressure side of oil pump and pushed thru filter and thruout engine.
Last edited by Jackie Paper; Aug 2, 2023 at 12:50 PM.
Cruiser
Joined: Jul 2023
Posts: 143
Likes: 22
From: California
Only addressing bubbles.
Unlike car motors that the oil in the pan is protected from a spinning crank so oil is not whipped up, what you see on a Harley is the returned scavenged oil.
It's going to be bubbly on top.
Pick up in the bottom of bag is relatively not so bubbly going back to pressure side of oil pump and pushed thru filter and thruout engine.
Unlike car motors that the oil in the pan is protected from a spinning crank so oil is not whipped up, what you see on a Harley is the returned scavenged oil.
It's going to be bubbly on top.
Pick up in the bottom of bag is relatively not so bubbly going back to pressure side of oil pump and pushed thru filter and thruout engine.
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