2018 M8----Sumping? Failures?
Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
Yep, yep... I totally understand and was happy to run the bike for the afternoon in order for them to work the issue - they in turn were grateful for my assistance and were standing-by at the ready when I returned sumping in full glory. 
My dealer is Tramontin HD in Hope, NJ. I am fortunate to have walked into a fantastic dealership for my first Harley - Truly great people there and they've been doing everything they can to help me out with this situation.
Got word this morning that a new 2019 is being built for my bike - apparently includes a new performance oil-pump plate / cover (?) that finally addresses the issue with the 117 sumping. I might actually have the bike this weekend.
My dealer is Tramontin HD in Hope, NJ. I am fortunate to have walked into a fantastic dealership for my first Harley - Truly great people there and they've been doing everything they can to help me out with this situation.
Got word this morning that a new 2019 is being built for my bike - apparently includes a new performance oil-pump plate / cover (?) that finally addresses the issue with the 117 sumping. I might actually have the bike this weekend.
Club Member
Joined: May 2018
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From: Tampa Bay Area
Member
Joined: Jul 2009
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Road Warrior
Joined: May 2011
Posts: 1,956
Likes: 439
From: florida
I guess the rumors from the illegitimate Harley techs and youtubers that sumping is only the higher stage kits is malarkey. Sorry for your luck. Wanting to buy and learn these new motors as a building platform but I’ll have to force myself to hold of a few more years. Or just keep buying TCs.
Tourer
Joined: Jul 2017
Posts: 259
Likes: 85
From: Tennessee
I would give them a couple of opportunities to fix it and then I would grenade it. These half-assed fixes don't get far with me. If you blow it they will have to replace with an entire new engine. This is not a new problem. It has been going on now for 24 months. Hundred, maybe thousands of bikes are having this problem. Clearly the MOCO engineers don't know what the cause is or they would have made the necessary changes in design months and months ago. Having a warranty doesn't do much good if they can't permanently fix it.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
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From: poway
Tourer
Joined: Jul 2017
Posts: 259
Likes: 85
From: Tennessee
Numbers
Well since Harley builds and sells almost a quarter of a million bikes a year, Im trying to figure out approximately how many have this issue.
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Member
Joined: Jul 2009
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That 280,000 M8 bikes is a fairly accurate and reliable # (within 5% accuracy).
So what's the incidence of sumping. Take if for what its worth, but I've been following the issue closely since I was one of the first guys to report sumping back in May of 2017. Based on anecdotal feedback from the forums, the PMs that guys have sent me and the reporting of sumping at my 2 local dealers, plus the fact that HD issued a major SB (1450) stating that all models of M8 are impacted, leads me to believe the incidence of sumping is between 1% and 10% of the M8s on the road SO FAR. I believe more will sump with more miles and more riding conditions, not to mention engines that have yet to be upgraded with Stage Kits. And that assumes alot of guys never share their sumping experience at all on social media.
So if you buy into that range of sumping incidence, then somewhere between 2800 and 28,000 M8 bikes have or will eventually sump. Are you feeling lucky today?
Road Warrior
Joined: Sep 2016
Posts: 1,887
Likes: 1,059
From: SE Washington
Damn shame this is happening. If it wasnt for this, the M8 is really a great motor.
First thing I did with my 17 RGU when I rode it home after the purchase was check the oil. It was halfway between hot full and add, perfect, but was surprised that it was also aerated; had a lot of bubbles in it. After letting it sit for a about 4 hrs, before going for an evening ride, I checked the oil again expecting it to be a bit lower. To my surprise it was a just barely over the hot full mark, but the engine was now cold. Never saw anything like it on my previous Harleys. Now with a stage 2 added and about 2500 miles on the bike, I asked my dealer's service tech to look into it while they were looking into a bad rattle issue. They found and fixed the rattle issue by replacing the lifters and cam chain tensioner, and also noticed the same bubbly, odd oil level issue. They checked for sumping and got 5 ounces at that time. At 7400 miles the biked finally displayed all the full on symptoms of sumping - hot, severe power loss, smell, etc. Over 10 ounces were found during the test.
My 18 FLHTK, built 5/18, has not displayed any of these issues in the first 1k miles. No aeration in the oil and oil level drops just a little after the bike cools as it should. For a stock bike, this thing really runs well. For warranty purposes, I want to wait a while before I install my S&S pump and all my other goodies from fuelmoto... maybe a year. So far so good.
First thing I did with my 17 RGU when I rode it home after the purchase was check the oil. It was halfway between hot full and add, perfect, but was surprised that it was also aerated; had a lot of bubbles in it. After letting it sit for a about 4 hrs, before going for an evening ride, I checked the oil again expecting it to be a bit lower. To my surprise it was a just barely over the hot full mark, but the engine was now cold. Never saw anything like it on my previous Harleys. Now with a stage 2 added and about 2500 miles on the bike, I asked my dealer's service tech to look into it while they were looking into a bad rattle issue. They found and fixed the rattle issue by replacing the lifters and cam chain tensioner, and also noticed the same bubbly, odd oil level issue. They checked for sumping and got 5 ounces at that time. At 7400 miles the biked finally displayed all the full on symptoms of sumping - hot, severe power loss, smell, etc. Over 10 ounces were found during the test.
My 18 FLHTK, built 5/18, has not displayed any of these issues in the first 1k miles. No aeration in the oil and oil level drops just a little after the bike cools as it should. For a stock bike, this thing really runs well. For warranty purposes, I want to wait a while before I install my S&S pump and all my other goodies from fuelmoto... maybe a year. So far so good.
Last edited by MTBIG G; Aug 2, 2018 at 10:20 PM.