Oil in throttlebody after breather bypass

[jeff]

Still have oil in throttlebody after bypass,only 4 qts. in bike--2017 roadglide. Any ideas? Thanks

[Nastytls]

Reversion? Whats the exhaust system?

[jeff]

fuelmoto header catless -mk45's thanks

[jeff]

More info- 124 cyclerama from Wes, mild porting,s&s pump and plate,stock throttlebody, vented crankcase and primary,fuel moto ac/dc aircleaner with 1 in. taller s&s filter.

[kd]

I take your OP to mean you are externally venting (not to intake anywhere).  I suspect you have piston ring gaps lined up.  If one side shows mare oil contamination than the other, that could be the culprit.  It happened to me on a fresh build.  It creates a tiny oil jet squirting into the combustion chamber and gets into the manifold on cam overlap.   

[jeff]

Thanks KD that's interesting. Makes sense. I wonder if they would keep spinning till they weren't aligned anymore? This is a new anomaly as the build has 3 thousand miles now. Thanks for input. And yes no breathing into intake.

[rich1]

I have the same issue. Mine is a stock 114 with excellent compression and leak down numbers. So it's not cam overlap or ring issues with mine.

[kd]

Thanks KD that's interesting. Makes sense. I wonder if they would keep spinning till they weren't aligned anymore? This is a new anomaly as the build has 3 thousand miles now. Thanks for input. And yes no breathing into intake.

I have the same issue. Mine is a stock 114 with excellent compression and leak down numbers. So it's not cam overlap or ring issues with mine.

This is what the rear piston looked like when the barrel was slipped off.  It happened on the dyno about 3 hrs into the tune. The compression in both cylinders was 205# and the leak down was less than 3%.  Both were even. We DID check both before we pulled the barrel. When doing the compression test I was holding the throttle plate open and noticed the oil. It was pooling in the rear runner. I bought the Nub tool to do the valve seals on the bike without head removal and even though they were perfect including the guides I changed the seals anyway . After consulting with Tom Reiser (Tman) and Steve Cole on the phone, they both called ring alignment. The rear barrel was removed. BINGO They were so perfectly aligned you could pick it out 25 feet away. During this ordeal we ran a thread on here with my and others experience with this happening. I tried to find it but ran out of time so here's a pic for now.

I am not saying you definitely have this problem but it's worth considering. My experience was it did not effect compression or leak down in my engine. I do know my barrels and pistons measured near perfect and the rings were initially installed correctly. They just stalled on rotation.  A whisker home and new rings cured it. I will be interested to hear what your trouble shooting finds.  Who knows, it may be a head gasket.    A head gasket may build crankcase pressure and show up that way.

[Don D]

Ring number 2 is an oil scraper. That is about oil in combustion. Oil in the intake may be residual from when the vents were internal and no more infiltration is happening there. If the seals are leaking it will also put a tacky film in the ports. In this case the oil gets by the valves and into combustion.

[jeff]

Thanks KD I will look into this further obviously, I was thinking leakdown next but as you said might not show up. HD performance it's not residual as this is just occurring after 3 thousand miles since build and breather rerout. Thank for all input so far. Jeff

[Thermodyne]

Still have oil in throttlebody after bypass,only 4 qts. in bike--2017 roadglide. Any ideas? Thanks

Look at where you sealed off the original vents, its leaking somewhere.

[Sunny Jim]

This is not dissimilar my 124 , on my previous post on cylinder leak testing.
I had internal breathers initially but went to external. I would clean the oil out and after some freeway miles it would reappear. Yes I had some a small variation in comp from front to rear( approx 5psi Difference at around 250 psi) and a clear difference in cylinder leak test BUT, once that rear cylinder was taken off the ring alignment was evident despite the anomalies like carbon and glazing.