2000 Fatboy puking oil.
Thread Starter
|
Intermediate
Joined: Apr 2024
Posts: 41
Likes: 8
From: AZ
Sorry to say but...... If your oil tank is draining that fast, you have a problem with your oil pump, something is seriously wrong... You need to open up the cam chest and inspect the oil pump & the oil pump gerotors...
I wouldn't start or ride the bike until I found the problem...
Good luck with the disassembly and inspection... keep us posted
I wouldn't start or ride the bike until I found the problem...
Good luck with the disassembly and inspection... keep us posted
Club Member
Joined: Sep 2010
Posts: 15,435
Likes: 7,127
From: Beyond Fucital
The check valve (ball valve) in the oil pump is stuck open.
It's under 1 of the caps/plugs on top of the oil pump, the 1 over the oil line from the oil tank.
Probably gummed up. Clean it and reseat it. Might be time for a new spring too.
It's under 1 of the caps/plugs on top of the oil pump, the 1 over the oil line from the oil tank.
Probably gummed up. Clean it and reseat it. Might be time for a new spring too.
Thread Starter
|
Intermediate
Joined: Apr 2024
Posts: 41
Likes: 8
From: AZ
Can you please point out what your explaining.
Seasoned HDF Member
Joined: Sep 2008
Posts: 14,158
Likes: 11,247
From: San Diego, CA
The 2000 FatBoy was a Twin Cam engine, not an EVO engine.... There is no check ball valve in the oil pump.....
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,592
Likes: 6,435
From: Honah Lee
He got your year of bike wrong. On the EVO, it had an external oil pump, it used a check ball to prevent dumping the oil bag. It also added a pressure increase with the restriction to keep oil light off at idle.
If you take a pump pushing a certain amount of fluid and put a restriction in the line, pressure raises on pump side. Now of course, there is a slight volume lose on other side.
Unlike sleeve bearings in car that restrict oil flow and require pressure to push oil all the way to the furtherest bearing from oil pump, Harley roller bearing motors don't need a lot of pressure to get oil thru motor.
The size of the pump, 20W50 oil an a 5 micron easy flow filter gives them plenty of oil.
They have oil injectors at the base of the cylinders to help cool inside the piston. They have a pressure valve on them that only releases above 15 or so. TC idle oil pressure is about 12. The maximum is 35 and that's handled by the relief spring in the pump.
You don't want oil injectors working at idle. (EXC street stop lights) It can cook the oil and reduce lubrication life. Motor can take short term heat and cools off running.
That's in normal areas. Probably not so well in areas that run in the 100 degree Fahrenheit in the shade mess.
If you take a pump pushing a certain amount of fluid and put a restriction in the line, pressure raises on pump side. Now of course, there is a slight volume lose on other side.
Unlike sleeve bearings in car that restrict oil flow and require pressure to push oil all the way to the furtherest bearing from oil pump, Harley roller bearing motors don't need a lot of pressure to get oil thru motor.
The size of the pump, 20W50 oil an a 5 micron easy flow filter gives them plenty of oil.
They have oil injectors at the base of the cylinders to help cool inside the piston. They have a pressure valve on them that only releases above 15 or so. TC idle oil pressure is about 12. The maximum is 35 and that's handled by the relief spring in the pump.
You don't want oil injectors working at idle. (EXC street stop lights) It can cook the oil and reduce lubrication life. Motor can take short term heat and cools off running.
That's in normal areas. Probably not so well in areas that run in the 100 degree Fahrenheit in the shade mess.
Last edited by Jackie Paper; Apr 3, 2024 at 12:11 PM.
Seasoned HDF Member
Joined: Sep 2008
Posts: 14,158
Likes: 11,247
From: San Diego, CA
Sorry Shaggy520, if only it was going to be that easy....
In your diagram, you will need to inspect #4,5,6,7,& 8.... something is wrong with the fitment of these parts, if they are not broken, if your oil tank is draining that fast at shut-off. I suspect you will find a major problem with #4, or maybe something worse... sorry to report that to you.
Bottom line is the oil pump is scavenging oil back to the tank, not making pressure, and draining quickly when the engine is shut down... There is a serious issue with your pump. I will again caution you, do NOT start the engine until you find this problem.
Ranger was referencing #7 in the pic below. It is on an EVO and Shovelhead oil pump... sadly, the Twin cams did not retain a check valve feature in its design to stop backflow form the tank to the sump. That job was relegated to the gerotors in the oil pump housing. Their tight fitment is what keeps the oil up in the tank... no check valve.
Last edited by hattitude; Apr 3, 2024 at 08:51 AM.
Thread Starter
|
Intermediate
Joined: Apr 2024
Posts: 41
Likes: 8
From: AZ
Ahh I see, that's why I couldn't find it in the manual thank you.
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,592
Likes: 6,435
From: Honah Lee
My guess is o-ring 8 is shreded from a broken part. Keep in mind, Harleys didn't dowel the oil pump. I have always wonder why they didn't dowel with pins or use shoulder bolts to attach it.
They have you fitting it with temporary bolts with a taper spud on the end to center it on the crankshaft.
Absolutely ridiculous to center off tapped holes but that's the way it is.
If you go in there, expect to replace the chain tensioners.
They have you fitting it with temporary bolts with a taper spud on the end to center it on the crankshaft.
Absolutely ridiculous to center off tapped holes but that's the way it is.
If you go in there, expect to replace the chain tensioners.
Last edited by Jackie Paper; Apr 3, 2024 at 12:25 PM.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Club Member
Joined: Sep 2010
Posts: 15,435
Likes: 7,127
From: Beyond Fucital
ya, I jumped the gun and missed that part.
Thread Starter
|
Intermediate
Joined: Apr 2024
Posts: 41
Likes: 8
From: AZ
My guess is o-ring 8 is shreded from a broken part. Keep in mind, Harleys didn't dowel the oil pump. I have always wonder why they didn't dowel with pins or use shoulder bolts to attach it.
They have you fitting it with temporary bolts with a taper spud on the end to center it on the crankshaft.
Absolutely ridiculous to center off tapped holes but that's the way it is.
If you go in there, expect to replace the chain tensioners.
They have you fitting it with temporary bolts with a taper spud on the end to center it on the crankshaft.
Absolutely ridiculous to center off tapped holes but that's the way it is.
If you go in there, expect to replace the chain tensioners.