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Sumping symptoms?

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Old Feb 28, 2018 | 10:33 AM
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Default Sumping symptoms?

No, I don't have an M-8. I have a '17 Fatboy S. I was checking the oil the other day, and noticed it was sort of thick and sludge-like. I have less than 5,000 miles on the bike.

I took it to the dealer and got them to change the oil right then. The service guy said softails were prone to sumping and that that was probably the problem.

All this being said, the bike runs fine.

I know the M-8s are having problems with sumping, but does anybody know anything about sumping issues with the Twin Cams?
 
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Old Feb 28, 2018 | 10:41 AM
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Was the engine at operating temp when you checked it?
 
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Old Feb 28, 2018 | 12:31 PM
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Originally Posted by jkinner
Was the engine at operating temp when you checked it?
Yeah, I checked it once cold and once hot and it was the same, semi-gunky. Not god-awful gunky, but it seemed to me for a new bike with low miles it looked worse than it should.
 
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Old Feb 28, 2018 | 12:44 PM
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All these years (decades ) and they can't fix this problem

My 00 does it.
If it sits for 2 or 3 weeks, and I pull the stick, it doesn't even register.
 
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Old Feb 28, 2018 | 02:30 PM
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Mine has gone down a bit when I haven't started it in a while, though I only checked it once, to be honest I check it post ride and just start it the next time, never had a problem, it's a 16 Deluxe with over 12k on her. I use SYN-3 never noticed it being too thick or any sludge.
 
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Old Feb 28, 2018 | 03:14 PM
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My '09 is the same. I fire her up every once in a while to circualte the oil but it empties back into the sump (?) after a few weeks. Mine gets changed every fall after the last ride.
 
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Old Feb 28, 2018 | 03:55 PM
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Change the check ball in the oil pump inlet valve. And maybe lap the seat to make sure.
 
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Old Mar 1, 2018 | 07:37 AM
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Originally Posted by adm
Change the check ball in the oil pump inlet valve. And maybe lap the seat to make sure.
?????
 
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Old Mar 1, 2018 | 07:42 AM
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Originally Posted by tmac00333
?????
That's an Evo and Shovel and Pan thing man don't think thew Twinkies work like that hey.
Man you've changed the oil and you're aware now that you may have been told porkies about you're new bike by the stealership.
Watch your oil but watch your HD shop guys more.
You're bike may be running real hot and the oil is frying, DK customs has a few good ideas but I can't find the ****ers right now.
I personally would flush the new oil soonish just in case there's more gunk in it and a new filter.
You have a new bike with warranty and you know the shop has lied to. you go get 'em champ.
 

Last edited by badcooky; Mar 1, 2018 at 07:50 AM.
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Old Mar 1, 2018 | 09:49 AM
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Originally Posted by tmac00333

I took it to the dealer and got them to change the oil right then. The service guy said softails were prone to sumping and that that was probably the problem.

All this being said, the bike runs fine.
The dealer was kinda right.....

There is a difference between:

1) "sumping"

2) The TWIN CAM, softail issue of oil flowing from the tank, past the pump, and into the sump... when the bike sits for long periods....

While twin cams have sumped, usually due to bad/missing main cam plate o-ring or damaged pump, most have the 2nd issue and incorrectly call it sumping...

Sumping is when oil collects in the sump when the engine is running... causing a loss of power as you increase rpm, and possible overheating the engine and causing damage...

The second issue is when oil collects in the sump, when the engine is off. It could be caused by several things, including worn oil pump, but doesn't cause any harm. If you let your bike idle/low rpm for a minute or two before hammering it, the oil will all be pumped back into the oil bag (tank) and the bike runs normally.

The worse thing that usually happens is that someone checks their oil level on a cold engine that has sit for a period of time. They see the low oil level, add a quart, then when their bike is warming up, it shoots oil out the dipstick because it is way over filled.... (if you search, you will see a few threads about this)

As far as "sludge-like" oil, not sure about that.... it could be due to overheating, but if your bike was actually "Sumping", and thus leading to the overheating, you would notice definite performance issues....
 

Last edited by hattitude; Mar 1, 2018 at 09:55 AM.
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