M8 Sumping issues
Grand HDF Member
Joined: Nov 2017
Posts: 4,251
Likes: 3,132
From: Texas
Triumph900 can clarify anything I get wrong here, but my understanding of his situation was that he.doesn't bounce off the rev limiter, that his bike wasn't overheated, and that he never experienced loss of power. The issue he took it in for was a slight leak from the lifter covers. He asked about sumping, and the service writer or mechanic said something like "never heard of it" but that was the eventual diagnosis.
Since this is the only report I have ever seen where a Softail is reported to have sumped, and since the symptoms don't sound like sumping, I have wondered if this isn't a case of misdiagnosis. Perhaps triumph900 was told it was sumping when the true issue was an oil pump failure or some other issue.
Road Captain
Joined: Mar 2017
Posts: 635
Likes: 35
From: No Cal
2017 Road Glide 25,000 miles, put in shop a couple of weeks ago starting feeling vibration that eventually turned into a engine knock. Long story short will be getting a new motor sumping issues and flywheel was to tight. Stock motor still had 6 months left on factory warranty. Knock was piston rod , damage to lifters,cam,pistons, and sleeves. Flywheel being to tight caused the pistons to twist sideways in sleeves, I had no idea about the flywheel tolerances until today. Supposed to be getting the 4th generation oil pump with new motor, Oh well I was one of the guys that used to say my M8 has had no problems.
Seasoned HDF Member
Joined: Sep 2008
Posts: 14,143
Likes: 11,218
From: San Diego, CA
2017 Road Glide 25,000 miles, put in shop a couple of weeks ago starting feeling vibration that eventually turned into a engine knock. Long story short will be getting a new motor sumping issues and flywheel was to tight. Stock motor still had 6 months left on factory warranty. Knock was piston rod , damage to lifters,cam,pistons, and sleeves. Flywheel being to tight caused the pistons to twist sideways in sleeves, I had no idea about the flywheel tolerances until today. Supposed to be getting the 4th generation oil pump with new motor, Oh well I was one of the guys that used to say my M8 has had no problems.
The scary part is how many will say, "Oh well I was one of the guys that used to say my M8 has had no problems," but they won't have a reason to say it until they are 6 months PAST warranty.....
That's the reason I cancelled my plans to upgrade to an M8.....
I was going to upgrade to an M8 as soon as I was convinced they solved the problem... not so sure I will now...
Road Captain
Joined: Mar 2017
Posts: 635
Likes: 35
From: No Cal
Yep, I got lucky that I rode mine enough that it happened now, would've been fu…. if I didn't and this happened middle of next year. Just glad that they're replacing motor, hopefully this won't happen again.
Stellar HDF Member
Joined: Jan 2013
Posts: 2,747
Likes: 419
From: Vermont
Having owned Harleys since the 1980 Evo days,and reading all the issues folks are experiencing with the m8 motor, I have been wondering if the oil Sumping problem may be caused by the oil being aireated. Just thinking of what has changed over the last thirty years of Harley vtwin motor design. To me it seems the issues started with the counterbalancers in the new M8. Could it be as the spin they aireate the oil which the foats to the point it looses it's viscosity and stops it lubrication ability to the point the engine sezes ? Has anyone tried to eliminate the counterbalancers to see if that would end the problem? Even though I would love to own a new machine, I can't bring myself to purchase one until Harley resolves these issues. If it is the case design has anyone tried after market cases to see if they are part of the solution? I will sit out of the trade in my dealer offered me on a new 19 until The issues are resolved.
THERE ARE NO NEW ENGINE CASE.......pure rumor by one knuckle head
I personal don't trust any capacities...air pressures or shock adjustments they recommend .....none are even close.
I personal have seen so many of these now with 58k 62k lots of 25k milage with no problems. Only one stumper and it turns out it was another stage 4 dealer install with damaged piston coolers AGAIN...
but in the end the few touring chassis with pan under trans that have been diagnosed as stumped are reported here....lol. Prolly 2 out of 10 of those were real. Rest were just crap engines that need to be warranted . ..
Last edited by Bumpandrun; Sep 24, 2018 at 08:01 AM.
Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
2017 Road Glide 25,000 miles, put in shop a couple of weeks ago starting feeling vibration that eventually turned into a engine knock. Long story short will be getting a new motor sumping issues and flywheel was to tight. Stock motor still had 6 months left on factory warranty. Knock was piston rod , damage to lifters,cam,pistons, and sleeves. Flywheel being to tight caused the pistons to twist sideways in sleeves, I had no idea about the flywheel tolerances until today. Supposed to be getting the 4th generation oil pump with new motor, Oh well I was one of the guys that used to say my M8 has had no problems.
Road Captain
Joined: Mar 2017
Posts: 635
Likes: 35
From: No Cal
I suspect you had various levels of sumping occurring from the beginning. Never enough to shut you down but enough to create overheating that caused bearing damage throughout the engine. Eventually that excessive bearing damage caught up to your engine causing the piston and flywheel tightness. Personally I believe this is happening on MANY M8 bikes where owners just dont recognize low levels of sumping. Sadly many more bike owners like yourself will figure it out too late after their warranties have expired
Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
Yeah, bike always ran fine until the day I started feeling the vibration in the handlebars. They called today going to send me a new short block, new oil pump, will be using my heads, they said heads was the only part that wasn't damaged. Now I have to decide do I want to go stage 3 or 4 since labor would be free.
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Road Captain
Joined: Mar 2017
Posts: 635
Likes: 35
From: No Cal
Looks like the 2019s are now sumping. Very sad and hugely disappointing. The M8 is going to need a complete redesign if a completely stock 2019 CVO RG sumps and dumps a huge volume of boiling oiling through the Crank Position Sensor. https://www.hdforums.com/forum/screa...l#post17709640
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