2015 Ultra Limited with 135000 kms on it. Yesterday started all 3 hole oil change. When I drained the primary at least 2 liters of oil drained out. Anyone else had this issue? I am going to replace the crank seal and spacer but is there other places I should look at? Thanks

 

Is the engine level low or tranny? A leaking sprocket shaft spacer, crank seal behind priamary will transfer engine oil. I have never had the tranny oil transfer to primary. They mainly talk about it on M8s, but I have also heard it started before that. Maybe they changed starters in 2007, but it got to be more of an issue with bigger and hotter engines. Not saying this case, just a theory I have heard.

But check oil levels.

 

1. Did you change all three holes previously and use the recommended amounts of fluid?
2. Have you had to add engine oil?
3. How much was drained out of the transmission.
4. There is a service bulletin about transmission to primary oil transfer; however, do not know if it covers your year bike or not.
5. See attachment below.



NOTE:
The above information, while credible, is worth what you paid for it and should not be considered gospel.
Do due diligence, research and have a H-D Field Service Manual before working on your bike.
You will probably have many opinions and suggestions presented; make sure you research the person providing the helpful information as there are some who provide good information that is useful and some who speak out of other orifices with gibberish. You will figure out this quickly.

 

The vent has come to prominence with the M8s. I have asked but never really got a clear answer why the primary after decades now needs a vent. He does not have an M8. If he had an extra liter in from the tranny, the tranny would be dry. Which I have heard of.

The seal behind the stator, sprocket shaft seal, also fails and transfers oil from engine to primary. I would check oil levels before I went to far.

I don't measure my oil coming out. Not bad idea, but I just still a big oil pan under it. Are you sure you have an extra liter?

 

Just FYI.... primaries have been vented for years....

The Twin Cam engines all had the same primary venting from the factory, that the M8's also have from the factory.

The primaries are vented through the hollow transmission main shaft, that the clutch release pushrod uses, between the primary and the trans side cover where the clutch cable/hydraulic slave lives. Any pressure is then released out the transmission vent

That venting was always good enough for the Twin Cams. Something in the M8 redesign caused trans fluid to migrate from the transmission to the primary via that hollow main shaft. They experimented with a few other options and then found an additional vent on the primary itself would alleviate almost all transmission oil migration to the primary. I've read about a few, rare cases where M8s with the new primary vent, have still had a trans oil migration issue.

Usually, on the rare occasions when a Twin Cam primary has fluid build up (not from being overfilled during a service) it would be engine oil being pushed past a leaking left-side sprocket shaft oil seal into the primary from Crankcase pressure.

I'm not an experienced Harley tech, but I don't recall hearing of case where trans oil has migrated into a Twin Cam primary....

 

The 5 speeds also had slight venting through jack shaft in starters.

 

Always change the 3 holes and yes recommended amounts. I did add a liter of engine oil. I didn't check how much came out of trans because I drained both at once but used separate container for primary which is how I noticed. I saw a bulletin about my year of bike and it says replace crank seal and spacer. I do have a manual. Thanks for replying

 

I used a separate container for primary that's how I found out. Poured the oil into 2 empty one liter containers, filled them both

 

Set all your lube levels correctly, then check them at intervals, make use you know what is happening before you start replacing parts.

Be careful who you listen to on this forum, there is one who will answer you who just babbles gibberish and talks about himself.

It will be obvious who he is.

 

If you didn't check engine oil or tranny oil, all you can do is ride it and check. On TCs I suspect more likely the engine is flowing into primary. An entire liter would leave your tranny about dry.