Milwaukee 8 Engine Problems
Road Warrior
Joined: Nov 2022
Posts: 1,538
Likes: 542
From: MN
Road Captain
Joined: Apr 2020
Posts: 655
Likes: 370
From: Gilbert, AZ
Not disagreeing with you as I believe that the "new" oil pumps are fine, but I replaced mine in my 22RGS for the piece of mind. If I get oil pump issues, then you are proven right. If I don't get any issues does that prove I was right?
Road Warrior
Joined: Sep 2016
Posts: 1,887
Likes: 1,059
From: SE Washington
Like I said before, there's nothing wrong with installing an aftermarket S&S or Fueling (or even HD SE) oil pump & cam plate. They're all good with the added benefit of slightly better cooling from the extra oil flow. However, the factory oil pump has more than proven itself.
Seasoned HDF Member
Joined: Apr 2008
Posts: 23,399
Likes: 8,509
From: Spartan Country, Michigan
So after reading all this, I am confused. Have a 2021 Street Glide with 12k miles. According to some I should replace the oil pump. And according to others, I should not. And then some say I need new wheel bearings. And maybe, or maybe not a new tune.
My question is this.... who should I listen to? Who is the resident expert here that can provide good, solid advice? There are some here that will turn a thread with a good question into something completely unrelated. Who do I believe? Those from the upper midwest? Those from the deep south? Westerners? Who?
My question is this.... who should I listen to? Who is the resident expert here that can provide good, solid advice? There are some here that will turn a thread with a good question into something completely unrelated. Who do I believe? Those from the upper midwest? Those from the deep south? Westerners? Who?
Grand HDF Member
Joined: Aug 2020
Posts: 4,798
Likes: 5,889
From: Knoxville
So after reading all this, I am confused. Have a 2021 Street Glide with 12k miles. According to some I should replace the oil pump. And according to others, I should not. And then some say I need new wheel bearings. And maybe, or maybe not a new tune.
My question is this.... who should I listen to? Who is the resident expert here that can provide good, solid advice? There are some here that will turn a thread with a good question into something completely unrelated. Who do I believe? Those from the upper midwest? Those from the deep south? Westerners? Who?
My question is this.... who should I listen to? Who is the resident expert here that can provide good, solid advice? There are some here that will turn a thread with a good question into something completely unrelated. Who do I believe? Those from the upper midwest? Those from the deep south? Westerners? Who?
Seasoned HDF Member
Joined: May 2008
Posts: 21,131
Likes: 12,691
From: South Carolina
I bet we can all agree on who NOT to listen to...
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Cruiser
Joined: Mar 2007
Posts: 163
Likes: 32
From: Amsterdam , The Netherlands
One of the theories I heard is, it is more promiment in touring bikes, because they get rode more, and being rode on long days they get hotter.
One theory was this even started with 103" and getting hotter. I wonder if 96/6 speed and mounting starter directly to primary, which in the past added a small amount of venting.
One interesting thing is the change in fluid levels in 6 speed trannys and primarys. Did they know something was going on?
Never had a primary vent.
Replacing oil pump, on new machine is BS, especically if you have to pay for it.
One theory was this even started with 103" and getting hotter. I wonder if 96/6 speed and mounting starter directly to primary, which in the past added a small amount of venting.
One interesting thing is the change in fluid levels in 6 speed trannys and primarys. Did they know something was going on?
Never had a primary vent.
Replacing oil pump, on new machine is BS, especically if you have to pay for it.
This issue only occured in M8 engines which were equipped with the hydraulic clutches.
Due to the shape of the gasket between the trapdoor and the inner side cover , which closes only the outer edge of the transmission case , and NOT the space where the rubber cap of the actuator is situated
What happened , was that the actuator also worked like a kind of "balloon pump" by sucking transmission oil through the tiny openings what the gasket did not cover., and press that collected oil through the hollow shaft into the primary , due to these two compartments shared the same closed inner atmosphere.
By making that closed atmosphere leak ( by installing that rubber vent ) , the unwanted "balloon pump" effect had been abolished..
It maybe sounds all a little confusing , but when you ( f.i.) should look up the picture at page 7 - 7 , fig. 4.6b of the Clymer M8 manual , it all will be clear.
Last edited by sjoko; Sep 8, 2023 at 07:36 AM.
My 2019 Limited has only needed the primary transfer fix in 40k miles.
Pure stock except for de-catted header and S&S slip[ ons.
Compared to my 07, 09, 12 cvo, 13 and 14 Twin cams, this bike is better in every respect.
Edited to add: This is the first Harley I've owned that has zero blow by indicated by a clean intake and butterfly inside the throttle body. I worried the first time I cleaned the A/C that I maybe had no oil in my top end....
And it's the first Harley I've owned that has no clicking, clacking, tapping, or sewing machine noises.
Uses no oil. Gets roughly 43mpg on average.
I've ridden it from Tx to Ca to D.C. and back. Even across the desert at 85mph in 110 degree heat. rftw.us
Pure stock except for de-catted header and S&S slip[ ons.
Compared to my 07, 09, 12 cvo, 13 and 14 Twin cams, this bike is better in every respect.
Edited to add: This is the first Harley I've owned that has zero blow by indicated by a clean intake and butterfly inside the throttle body. I worried the first time I cleaned the A/C that I maybe had no oil in my top end....
And it's the first Harley I've owned that has no clicking, clacking, tapping, or sewing machine noises.
Uses no oil. Gets roughly 43mpg on average.
I've ridden it from Tx to Ca to D.C. and back. Even across the desert at 85mph in 110 degree heat. rftw.us
Last edited by r0de_runr; Sep 8, 2023 at 06:18 AM.
