Sumping? Questiom
Seasoned HDF Member
Joined: Sep 2009
Posts: 17,144
Likes: 6,166
From: SE Michigan
That would be me.
I must be something of a miracle then. Also, I dont think I agree with your assessment that its always a failure. I dont think we've seen oil pump "failures", other than various versions of it not being up to the job, but they don't malfunction per se.
Yep.
"Sumping" has been associated with a variety of engine failures. Looking through sumping-related threads reveals this very clearly. It isn't just some amorphous nobody-knows-why characteristic of poor engineering and design. Almost all instances of sumping are related to a component failure inside the engine. A failed oil pump. A defective case (hole in it). A failed balance gear. A blocked oil or breather passage. Etc.
I believe this is why most of the sumping cases are related to "upgrades" done on otherwise perfectly fine engines, and done poorly. One guy here recently called for a class action suit against Harley because of this and other problems, and then a few weeks later revealed that his sumping was cause by a screwed-up "upgrade."
Some engines have sumped even though there had been no "upgrading" on them. These are rare, extremely rare. And probably result from faulty assembly at the factory. Sometimes things leave the factory defective. But it is extremely rare.
I believe this is why most of the sumping cases are related to "upgrades" done on otherwise perfectly fine engines, and done poorly. One guy here recently called for a class action suit against Harley because of this and other problems, and then a few weeks later revealed that his sumping was cause by a screwed-up "upgrade."
Some engines have sumped even though there had been no "upgrading" on them. These are rare, extremely rare. And probably result from faulty assembly at the factory. Sometimes things leave the factory defective. But it is extremely rare.
Yep.
Last edited by Keithhu; Sep 30, 2019 at 07:18 PM.
Club Member
Joined: Mar 2009
Posts: 66,110
Likes: 51,394
From: Niles Canyon Ca.
Yeah, still trying to get my head around the odds of that and I can't win so much as a $2 lottery ticket...
HDF Community Team
Joined: Mar 2008
Posts: 1,892
Likes: 552
From: NH
Where ya been hiding? Have your questions been answered? Do you have any more?
Road Captain
Joined: May 2012
Posts: 614
Likes: 79
From: Virginia
"Sumping" has been associated with a variety of engine failures. Looking through sumping-related threads reveals this very clearly. It isn't just some amorphous nobody-knows-why characteristic of poor engineering and design. Almost all instances of sumping are related to a component failure inside the engine. A failed oil pump. A defective case (hole in it). A failed balance gear. A blocked oil or breather passage. Etc.
I believe this is why most of the sumping cases are related to "upgrades" done on otherwise perfectly fine engines, and done poorly. One guy here recently called for a class action suit against Harley because of this and other problems, and then a few weeks later revealed that his sumping was cause by a screwed-up "upgrade."
Some engines have sumped even though there had been no "upgrading" on them. These are rare, extremely rare. And probably result from faulty assembly at the factory. Sometimes things leave the factory defective. But it is extremely rare.
I believe this is why most of the sumping cases are related to "upgrades" done on otherwise perfectly fine engines, and done poorly. One guy here recently called for a class action suit against Harley because of this and other problems, and then a few weeks later revealed that his sumping was cause by a screwed-up "upgrade."
Some engines have sumped even though there had been no "upgrading" on them. These are rare, extremely rare. And probably result from faulty assembly at the factory. Sometimes things leave the factory defective. But it is extremely rare.
Im one of the lucky few I guess. 2018 100% stock 114 started sumping at ~1500 miles.
Cruiser
Joined: Aug 2018
Posts: 137
Likes: 52
From: Dresden, OH
Just found today that my 2018 street glide, that is stock except slip-ons, has sumped. Took it to the dealer who is going to do the vent repair. Hope this repair works. Any input on anything I should request from the dealer, or watch out for would be appreciated.
Seasoned HDF Member
Joined: Sep 2009
Posts: 17,144
Likes: 6,166
From: SE Michigan
I doubt it will because the vent addresses the transmission fluid tranfer to the primary, not sumping.
Cruiser
Joined: Aug 2018
Posts: 137
Likes: 52
From: Dresden, OH
Thanks Keith. You are correct that I confused the two issues.
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Road Master
Joined: Jan 2016
Posts: 1,143
Likes: 433
From: Menifee, CA
As far as what failures caused engines to sump and die, very little is known down here in the provinces. One or two here at HDF has reported being present when a sumped motor was "partially" torn down at the dealer before it was crated and shipped back to the factory for analysis. I am certain the engineering folk at the factory are aware of exactly what issue caused each and every sump situation, because they are experts who carefully tore down those engines and did a scientific, measured analysis. But we at HDF are not in the feedback loop, so we don't get reports about what the engineers found in those broken motors.
However we do know a few things. I've been following this in HDF for two years, and there is quite a lot of user level information posted here. Riders have had engines sump due to component failures. One example, the guy who posted pics of a hole in a case in the cam chest. Another posted pics of a balance gear that disintegrated and lodged a tooth in the oil pump. Another with a breather passage blocked due to a botched "upgrade." Most, however, seem to have no idea what caused the sumping failure. The motor was removed and replaced, the dead one shipped back to the factory.
A careful analysis would require complete disassembly of the engine. Measurements done by qualified experts. A rider standing by while heads and cylinders are removed, and peering down into the holes, does not constitute careful engineering alalysis. So rider saying he witnessed the "tear down" of the motor and observed no particular failure doesn't prove anything whatever. Moreover, I seriously doubt that the average Harley dealer shop has the kind of technical expertise to perform such analysis.
