Hey guys! I need your help

I have a 2003 fatboy. The last week i have had the oil dip stick pop out 3 times with oil spraying everywhere. I assume that i have high pressure, my oil levels are good. I rode for about an hour last night while holding down the dipstick to prevent it from popping, i realized afterwards that the oil found its way out through the primary shifter seal.

What should i look for ? Blocked oil lines or rebuild umbrellas under rocker covers?

The breathers are not blocked or pinched. When i removed a/c breathers and started motor i did not feel any air blowing out of the breather holes is that normal?

Thank you!

 

Did this just happened suddenly, or after you did some work/maintenance on your bike....??

Have you recently worked on anything around the air cleaner or in the heads....???

The umbrella valves in the breather assemblies won't fail in a way to block crankcase venting... They are more likely to cause a problem when put in backwards while working in the rocker boxes. The early 2003 bikes had the old style breather assemblies, and there is a new updated one (part #17025-03A) that I switched to on my 2003 Heritage when I did my cam plate upgrade.

Obviously barring any kind of mechanical problem like bad piston rings that can lead to severe crank case pressure, or improper install of the breather assemblies during rocker arm work... there are several things that can/do cause this..

Some people have accidentally pinched/blocked the breather holes/hoses in the air cleaner back plate when doing work/maintenance that required its removal...

Another cause of the dipstick popping out is from checking the oil level in a softail when it's cold. Often some oil will seep past the oil pump and settle in the sump. Then when you check, and fill the engine cold, after start & warm-up, the oil is pumped back into the oil tank. The extra oil forces out the dip stick and causes a mess...

But the biggest problem is usually the dipstick o-ring wearing out. That can allow for the dipstick come out during normal riding...

There were two different dipsticks used in twin cam softails. The first, which I believe you have in your 2003, is pictured below. It has an o-ring that can wear out. You can get a new o-ring (part #11345) and it should fix that issue..




Later softails, I forget what year, went to a dipstick without a separate o-ring, but rather had ridges formed in the dipstick cap, to hold the dipstick in place. It is now the superseded part to the older one with a separate o-ring. It is pictured below.




When the new style dipstick gets worn, people will add an o-ring to it, that will in most cases hold it in place..




Good luck with your fix....

 

Hi Hattitude!

Thank you so much for all that info !

Yes it just happened suddenly, i did not do any work on the breathers or head. The only thing i did was a dyno and remap at the dealer. But it was running fine after the dyno for about a month.

I ordered a new o ring for the dip stick. Im not sure its that because when i hold down the dipstick while riding the oil will find other ways to leak out, through a bad shifter seal this time. I for sure have some sort of pressure in there.

 

I missed that part... I would do a leak down test... it will tell you the condition of rings and valve seats/seals so you can just check excessive blow-by off your list of possible causes.... It's not unheard of for dyno runs to lead to issues..

They did update the early breather assemblies as a running production change. I always believed it was for a better, more efficient breather assembly..., But I don't know for sure. It's possible they had issues with the early version having a failure of some kind which led to the upgrade... The MoCo rarely spends money on an running production change, if something is not costing them money in warranty repairs..

Keep us updated...

 

Will do, ill keep u updated thxs again! 🙂🙏

 

Now that i think of it, why would crankcase pressure blow a seal out of the shifter seal which is located in the primary? Are they not separate components with different oils?

 

https://www.hdforums.com/forum/softa...-blew-off.html

 

It wouldn't... They are separate.

I focused on you saying, "I for sure have some sort of pressure in there (crankcase)". I didn't notice you said it was leaking through the "shifter" seal....

The primary and trans are connected via the hollow main shaft that the clutch pushrod goes through, and they share a vent... but the engine is separate from them both. It has a seal on the engine case, on the primary side that keeps their fluids separate...

It is rare, but there have been cases of the engine case oil seal leaking engine oil into the primary... but again, pretty rare...

Excessive blow-by, causing high crankcase pressure, can cause your dipstick to pop out. If the new dip stick o-ring doesn't hold the dipstick in, then a pressure test & leak down test would be in order.... IMHO

 

After more verification the leak is coming from the crankcase upper bolt. Can the pressure be exiting from this bolt? I will change the dip stick o ring and see what happens, but im sure i have pressure some how.