Twin Cam blowing oil from breather

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Mar 24, 2022 | 08:55 AM

Eastcoast Jim

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From: Lake Wales, Fl

Twin Cam blowing oil from breather

A question for Y'all --It's a 03 Road King with a stout 95" - 230K miles - 170 on a complete rebuild - trued & welded MOCO wheels - Screamin Eagle Cylinders at that time. Bored .020 at 150 K miles. Wisceo pistons & rings- about 60-70 K on these rings . The heads are vented to the atmosphere into a catch can. It's blowing a LOT of oil, The engine still runs strong- no change there - cranks at 200+ , fueling oil pump & cam plate.- Welded flywheels - Woods 6H Gear drive & all the other stuff.
I just did the umbrellas & breather assembly - no change
The question is - Before I do new rings - is there any else I should look at?
Thanks - Jim

Mar 24, 2022 | 12:49 PM

djl

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From: san antonio

Compression and leak down test are the next steps before doing anything.

Mar 24, 2022 | 01:17 PM

07UltraGuy

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From: SoCal

Before I even bothered with a compression test, I would check the oil level... is it possibly over-filled?

Mar 24, 2022 | 06:45 PM

TexasScooterTrash

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From: Dallas, Texas

With all that work and the mileage, did ya ever replace the Umbrella Valves in the heads? I'd look at that 1st.

Mar 24, 2022 | 07:02 PM

Max Headflow

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From: poway

If the compression is OK, pull the oil pump and replace the O ring between the pump and the case..

Mar 24, 2022 | 09:48 PM

Eastcoast Jim

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From: Lake Wales, Fl

Quote:

Originally Posted by Max Headflow

If the compression is OK, pull the oil pump and replace the O ring between the pump and the case..

OK - Thanks - I have some oil pump o rings, That could fail from just age & miles? That pump has been in there for maybe 140 -50K miles - If that fails then there will be a problem with scavenging the oil ? Right ?

Mar 24, 2022 | 09:56 PM

Max Headflow

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From: poway

Quote:

Originally Posted by Eastcoast Jim

Heat kill the rubber, makes the O ring hard. Make sure that the new O rings are Viton.

The oil pump is really 2 pumps, feed and scavenge. If the scavenge pump fails, it will cause the scavenging problem.. Make sure the scavenge pump is still in good condition.