2018 M8----Sumping? Failures?
HDF Community Team
Joined: Mar 2008
Posts: 1,893
Likes: 552
From: NH
Heatwave, yes I had 2 of the newest oil pumps continue to cause the sumping . Newest as of May 2018 and again July of 18. The last time I got a new long engine block. I had to make the pump change or Id never have trusted the bike. H-D paid for the first 2 repairs but when the engine died they pulled up the aftermarket PV tune and voided my warranty. Bike seems good as long as I dont speed shift in high revs 4000-4500rpms.
Tourer
Joined: Feb 2016
Posts: 486
Likes: 155
From: British Columbia
Just to confirm what Max Headflow and yourself have experienced. Last summer while giving my ThunderMax tuner higher RPM points to data log for download to adjustment, I was holding my 2010 Twin Cam at various extended higher RPM's (5000 plus) for 10,20,30 second intervals. Normally I don't ride all that aggressive. While I didn't experience any physical issues of imminent failure, I did drain off oil while threading out the sump plug. About half a pint of engine oil ran out. A little perplexing for me not having seen this accumulation of oil in the past. So I believe Higher sustained RPM's are a recipe for disastrous sumping. At least one of them anyway. If I do get back in to the cam chest, I'll likely be installing a Fueling oil pump and cam plate.
Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
Its important to follow the steps outlined in SB1450 before draining the oil from the crankcase for measurement. Its not unusual or harmful for oil to briefly build in the crankcase so longer as it is quickly pumped out. The issue is when the pump either can’t remove the oil or the crankcase inflow exceeds the outflow for an extended period. That’s why the steps in SB1450 need to be precisely followed before concluding the engine is sumping.
Personally I wouldn’t trust the crankcase oil findings unless the SB1450 procedure were performed AFTER a healthy 60-90 minute ride.
Personally I wouldn’t trust the crankcase oil findings unless the SB1450 procedure were performed AFTER a healthy 60-90 minute ride.
Last edited by Heatwave; Jan 13, 2019 at 05:10 PM.
Just to confirm what Max Headflow and yourself have experienced. Last summer while giving my ThunderMax tuner higher RPM points to data log for download to adjustment, I was holding my 2010 Twin Cam at various extended higher RPM's (5000 plus) for 10,20,30 second intervals. Normally I don't ride all that aggressive. While I didn't experience any physical issues of imminent failure, I did drain off oil while threading out the sump plug. About half a pint of engine oil ran out. A little perplexing for me not having seen this accumulation of oil in the past. So I believe Higher sustained RPM's are a recipe for disastrous sumping. At least one of them anyway. If I do get back in to the cam chest, I'll likely be installing a Fueling oil pump and cam plate.
Advanced
Joined: Feb 2008
Posts: 89
Likes: 4
From: Md
The sumping is on the M8s not my Twin Cams. Ive had a 2008 screaming eagle RK. A 2011 stage 2 Fat Boy. and still have a 2013 stage 4 SG along with my 2018 Stage 4 SGS. I ride them hard and never ever had a sumping problem except for the 18 M8. Im not mechanically inclined at all but thats been my personal experiences.
Road Master
Joined: Nov 2011
Posts: 762
Likes: 264
From: Timnath, CO.
I have read (not experienced) of sumping issues with the TC's.
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Member
Joined: Jul 2009
Posts: 4,310
Likes: 1,079
Im not aware of multiple full threads with hundreds of posts dealing with sumping in the TC forum like there is with the M8s. In fact there are even more threads now posting on CVOHarley with 2019 CVOs that are sumping. Very discouraging.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,928
Likes: 8,032
From: poway
Probably because you haven't been around long enough.. Early TCs had issue. It was determined to be the result of bad oil pump alignment and possibly the material used for the inner pump O ring.. Baggers so has a known issue of spitting out the dipstick and oil all over the place which I suspect is the reason why they now screw in.. HD changed air vent line from the tank to the motor to fix this.. In 99-2000 this place didn't exist. There was a news ground and another group on Yahoo.. Maybe 1 or 2 others. They also has rear cam bearings self destruct, When they went, the motor would sump from the scavenge rotor being destroyed. HD added a 5 year/5000 mile warranty (IIRC) on the cam bearing failure.