2018 M8----Sumping? Failures?
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Joined: Feb 2008
Posts: 89
Likes: 4
From: Md
Looks like I unfortunately joined the HD M8 Sumping club. New 18 FLHXS w/Harley stage 4 kit and recommended oil pump per service Bulletin 1450, 1600 miles. Bought the week after the 18s came out. While riding Saturday I experience loss of power and bike running very rough. Pulled over, checked oil, 1 3/4 quarts low. I check my oil regularly, the day before it showed full. Walked to an auto parts store and picked up a few quarts. Added the oil until dipstick showed full. Fired up, bike ran great, low oil made no sense until I read this thread about sumping. Got home and the oil stick showed way way overfilled. Drained the excess out, dealer is picking up the bike in the next few days. This really sucks.
Tourer
Joined: Jul 2017
Posts: 449
Likes: 76
From: Oz
Looks like I unfortunately joined the HD M8 Sumping club. New 18 FLHXS w/Harley stage 4 kit and recommended oil pump per service Bulletin 1450, 1600 miles. Bought the week after the 18s came out. While riding Saturday I experience loss of power and bike running very rough. Pulled over, checked oil, 1 3/4 quarts low. I check my oil regularly, the day before it showed full. Walked to an auto parts store and picked up a few quarts. Added the oil until dipstick showed full. Fired up, bike ran great, low oil made no sense until I read this thread about sumping. Got home and the oil stick showed way way overfilled. Drained the excess out, dealer is picking up the bike in the next few days. This really sucks.
Grand HDF Member
Joined: Nov 2013
Posts: 3,807
Likes: 1,488
From: SW Washington State
Looks like I unfortunately joined the HD M8 Sumping club. New 18 FLHXS w/Harley stage 4 kit and recommended oil pump per service Bulletin 1450, 1600 miles. Bought the week after the 18s came out. While riding Saturday I experience loss of power and bike running very rough. Pulled over, checked oil, 1 3/4 quarts low. I check my oil regularly, the day before it showed full. Walked to an auto parts store and picked up a few quarts. Added the oil until dipstick showed full. Fired up, bike ran great, low oil made no sense until I read this thread about sumping. Got home and the oil stick showed way way overfilled. Drained the excess out, dealer is picking up the bike in the next few days. This really sucks.
Advanced
Joined: Feb 2008
Posts: 89
Likes: 4
From: Md
Sorry to hear this, I feel your pain though having had a 2017 stage III that failed myself.. So now what? a new kit? will you trust it? Really sucks. I had to walk away from my 2017 for a stock 2018. almost 6000 miles now, but every time I see a pic of my old bike I get really pissed.
Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
Looks like I unfortunately joined the HD M8 Sumping club. New 18 FLHXS w/Harley stage 4 kit and recommended oil pump per service Bulletin 1450, 1600 miles. Bought the week after the 18s came out. While riding Saturday I experience loss of power and bike running very rough. Pulled over, checked oil, 1 3/4 quarts low. I check my oil regularly, the day before it showed full. Walked to an auto parts store and picked up a few quarts. Added the oil until dipstick showed full. Fired up, bike ran great, low oil made no sense until I read this thread about sumping. Got home and the oil stick showed way way overfilled. Drained the excess out, dealer is picking up the bike in the next few days. This really sucks.
Last edited by Heatwave; Apr 2, 2018 at 03:34 PM.
Advanced
Joined: Feb 2008
Posts: 89
Likes: 4
From: Md
Sorry to hear this, I feel your pain though having had a 2017 stage III that failed myself.. So now what? a new kit? will you trust it? Really sucks. I had to walk away from my 2017 for a stock 2018. almost 6000 miles now, but every time I see a pic of my old bike I get really pissed.
Advanced
Joined: Feb 2008
Posts: 89
Likes: 4
From: Md
When did you have the Stage 4 upgrade installed? At delivery back in August or later? You might find this thread describing my sumping experience of value.... https://www.hdforums.com/forum/milwa...ddressing.html
Last edited by skiindean; Apr 2, 2018 at 03:54 PM.
Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
Bought bike 8/25/17. Stage 4 kit was installed and completed around 3 weeks later. Thanks for the heads up, it looks to be very informative. What I take from everything I’ve read thus far is that Harley still doesn’t have a definitive solution. If I have more engine issues after this go round I’m done with Harley. I waited a long time for my 18, and even longer for the fit mods. I couldn’t be more disappointed.
Hard to say. You had the oil pump installed before the latest oil pump design changes they made in mid October 2017. According to my local HD Dealer Rep that I've been dealing with, there have been "no reported sumping issues on any M8 bike since the last oil pump design was installed using the latest oil pump bolt torquing process".
I sure hope that's accurate because I am about to upgrade my 3rd 117 M8 engine to Stage 4 for the 3rd time. The entire install is being done at my local dealer but with onsite supervision by the dealer rep and HD technical support. There can be NO EXCUSES this time if there is a sumping engine failure. I will be starting a new thread to share the process, findings and results.
Last edited by Heatwave; Apr 2, 2018 at 04:14 PM.
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Grand HDF Member
Joined: Nov 2013
Posts: 3,807
Likes: 1,488
From: SW Washington State
Bought bike 8/25/17. Stage 4 kit was installed and completed around 3 weeks later. Thanks for the heads up, it looks to be very informative. What I take from everything Ive read thus far is that Harley still doesnt have a definitive solution. If I have more engine issues after this go round Im done with Harley. I waited a long time for my 18, and even longer for the fit mods. I couldnt be more disappointed.
