Milwaukee 8 Engine Problems
Club Member
Joined: Apr 2016
Posts: 11,535
Likes: 8,371
From: Inland NW
You should not be misleading people with that information
Cruiser
Joined: Mar 2007
Posts: 163
Likes: 32
From: Amsterdam , The Netherlands
How many (upgraded) stock oil pump versions have been made till now ?
Why couldnt they make a good one right from the beginning ?
Sorrry , but I've lost my faith in that a wee bit .
S&S and Feuling , ...they have made good and reliable oil pumps right from the start
That oil pump is the heart of my M8 engine , so it better can be a proven good one
( I've changed them out in my previous stage 2 EVO , -TC96 , -TC103 as well )
In my case it should not be wise at all to leave the stock oil pump in :
I run a S&S128ci kit , S&S475C cam , S&S alu. tappet cuffs , V&H X-headers , SE 6.8 injectors , no cat. , KessTech slip-ons , Trask vented transm. cover , K&N hi-flo filter kit ,....and ( of course ) the S&S oil pump.
It's good for 136 HP now
Last edited by sjoko; Aug 24, 2023 at 06:23 PM.
Club Member
Joined: Apr 2016
Posts: 11,535
Likes: 8,371
From: Inland NW
I will tell you :
How many (upgraded) stock oil pump versions have been made till now ?
Why couldnt they make a good one right from the beginning ?
In my case it should not be wise at all to leave the stock oil pump in :
I run a S&S128ci kit , S&S475C cam , S&S alu. tappet cuffs , V&H X-headers , SE 6.8 injectors , no cat. , KessTech slip-ons , Trask vented transm. cover , K&N hi-flo filter kit ,....and ( of course ) the S&S oil pump.
It's good for 136 HP now
How many (upgraded) stock oil pump versions have been made till now ?
Why couldnt they make a good one right from the beginning ?
In my case it should not be wise at all to leave the stock oil pump in :
I run a S&S128ci kit , S&S475C cam , S&S alu. tappet cuffs , V&H X-headers , SE 6.8 injectors , no cat. , KessTech slip-ons , Trask vented transm. cover , K&N hi-flo filter kit ,....and ( of course ) the S&S oil pump.
It's good for 136 HP now
We can compare the mod list all day, if you want. My 128 with all that and more has 20K miles on the latest version HD oil pump so far, without an issue.
My point was, you should not be telling new guys that are asking for advice that the sky is falling with the latest oil pump version.
Last edited by NorthWestern; Aug 24, 2023 at 08:34 PM.
Grand HDF Member
Joined: Aug 2020
Posts: 4,798
Likes: 5,889
From: Knoxville
Hi everyone, I am well aware that the early M8 engines from 2018 - 2020 had their fair share of mechanical issues. Am in right in thinking that the problems have been ironed out in the 2023 models? I currently have a 2015 twin cam and am think of upgrading to a new fatboy but I keep hearing things like stick with your twin cam
new M8s are nothing but trouble
Are they right? I am interested to hear from anyone that has one and whether theyve had a good or bad experience with it
Haters gonna hate.
M8 runs circles around Twinkies.
For every bad experience, 100s of great ones.
Leave the dark side.
Cruiser
Joined: Mar 2007
Posts: 163
Likes: 32
From: Amsterdam , The Netherlands
Whatever. Nobody said they did not make a mistake with the prior pumps. I am saying there is now verifiable proof that the latest version is in fact solid.
We can compare the mod list all day, if you want. My 128 with all that and more has 20K miles on the latest version HD oil pump so far, without an issue.
My point was, you should not be telling new guys that are asking for advice that the sky is falling with the latest oil pump version.
We can compare the mod list all day, if you want. My 128 with all that and more has 20K miles on the latest version HD oil pump so far, without an issue.
My point was, you should not be telling new guys that are asking for advice that the sky is falling with the latest oil pump version.
, ...but I will never hesitate to tell about certain flaws or weaker designs.Don't forget , that ALL the previous solutions were considered as being sufficient .
As long as you ride the bike nice and gently ,....and keep everything stock , or up to stage 1 ,..... it will last forever.
As soon as it is upgraded stage 2 ( ...or stage3 ,...or stage 4 ) you better go for S&S - , or Feuling pumps.
P.S.: That "new guy" is a TC103ci owner ,....and this counts for the TC engines as well , ....so in fact , "nothing new under the sun" ( I think )
Last edited by sjoko; Aug 25, 2023 at 11:24 AM.
Seasoned HDF Member
Joined: May 2012
Posts: 32,934
Likes: 36,031
From: Carlsbad, CA
Fixed it for you
Cruiser
Joined: Mar 2007
Posts: 163
Likes: 32
From: Amsterdam , The Netherlands
Whatever. Nobody said they did not make a mistake with the prior pumps. I am saying there is now verifiable proof that the latest version is in fact solid.
We can compare the mod list all day, if you want. My 128 with all that and more has 20K miles on the latest version HD oil pump so far, without an issue.
My point was, you should not be telling new guys that are asking for advice that the sky is falling with the latest oil pump version.
We can compare the mod list all day, if you want. My 128 with all that and more has 20K miles on the latest version HD oil pump so far, without an issue.
My point was, you should not be telling new guys that are asking for advice that the sky is falling with the latest oil pump version.
,...but there's another thing to be mentioned.There's more cavitation of the engine oil in the M8 , due to the balance shaft in the cranck case , which operates unintentionally also like a sort of "cream whipper" .
The scavenge part of the oil pump can suck up ( of course ) normal engine oil ,....but not oil foam that good. ( that's why I've chosen for the very best oil pump brand )
Another important upgrade to prevent "sumping" , is mounting the "Trask vented transmission cover" ( in case of stage 2 and up ) ,
otherwise a serious amount of carbon residue can also be build up on the pistons due to "blow by".
I wished that someone could tell me this all , before I was a "new guy" into the M8 world .
( ....and yes , I'm still a great fan of the Harley Davidson M8 ,...it's a very fine motorcycle !!! )
Last edited by sjoko; Aug 29, 2023 at 05:03 AM.
Road Master
Joined: Feb 2018
Posts: 801
Likes: 1,123
From: West Texas
I agree that the current Harley parts are fine. The aftermarket stuff is great, but is more costly than the current Harley oil pump. If you want the aftermarket stuff, great, but it is not necessary as any kind of blanket upgrade.
I have 31K miles on my late 2019 and haven't had a single issue. Mine has a stage 1 but is otherwise stock. Even bone stock, it is was best running Harley in stock form that I have owned.
I have 31K miles on my late 2019 and haven't had a single issue. Mine has a stage 1 but is otherwise stock. Even bone stock, it is was best running Harley in stock form that I have owned.
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Cruiser
Joined: Mar 2007
Posts: 163
Likes: 32
From: Amsterdam , The Netherlands
...... I have around 20K miles on the odometer of my 2019 Street Glide Special 114ci ( meanwhile upgraded into 128ci , since a period of two months )
The issues I've had :
- Loose ( wrong ) floaters in my front brake rotors. ( = solved under warranty , with assistance of HD BeNeLux , Europe )
- The so called "oil transfer issue" ( = solved under warranty , with assistance of HD BeNeLux , Europe )
- Serious carbon build up on the pistons , due to "blow by" ( over the very longest period it was Stage 1 and also Stage 2 with the HD SE447 torque cam )
This issue sometimes caused spark knock on hot days .
( and that's also the reason that I've mounted the Trask vented transmission cover now )
If there are doubts about that ,....tell me here , ...because then I will make/show pictures of my stock 114ci pistons to prove it .
The issues I've had :
- Loose ( wrong ) floaters in my front brake rotors. ( = solved under warranty , with assistance of HD BeNeLux , Europe )
- The so called "oil transfer issue" ( = solved under warranty , with assistance of HD BeNeLux , Europe )
- Serious carbon build up on the pistons , due to "blow by" ( over the very longest period it was Stage 1 and also Stage 2 with the HD SE447 torque cam )
This issue sometimes caused spark knock on hot days .
( and that's also the reason that I've mounted the Trask vented transmission cover now )
If there are doubts about that ,....tell me here , ...because then I will make/show pictures of my stock 114ci pistons to prove it .
Last edited by sjoko; Aug 29, 2023 at 12:49 PM.
