Oil pumping out the catch can

[N-gin]

Long story short
S&Sblock with man o war
Thayer plate and pump
Drilled rocker support to .125
4.180 bore 4.3/8 stroke
Anything after 3400 RPM it fills the catch can and down the side of the bike in under 10 min on highway. If over 4000 RPM it will fill it in under 4 minutes.

Do u guys think I need to drill the rocker plate bigger? I'm thinking it is not draining fast enough.
It's a new build and I just noticed after a highway cruise some time ago. Don't go on highway much cause all the streets are 55 and country road. But seems Everytime I go to highway it happens. This is the 3 time on the highway and third time it's done it, so I'm chalking it up to rpm. My gearing is 3.05.
Too many good parts in this engine to list. Hoban did the block for Dyna oiling.
Thoughts?

[N-gin]

I will add if riding around town I have no issues. And only water comes out of catch can, with just a hint of oil near the end of draining the can.

[Ohio HD]

I have the same size holes in the rocker supports, it should be more than enough. What type of oil return pass at the base of the cylinder, o-ring or a base gasket?

[Coff 06]

Maybe try lowering your oil level 1/2 quart.       Coff 06

[rigidthumper]

Check the leakdown, just to make sure it's a venting thing, not a blowby thing?

[Thermodyne]

How much oil are you pumping to the top of the motor?  Its either too much oil as the rpms come up.  Sumping preventing the oil from draining ( doubt that with a three stage pump) or its building blow by as the rpms go up.

With those big bores the piston skirts, or lack of become an issue.  Piston fit become critical.  If the skirt clearance loosens up you can get some rocking and loose the ring seal.  Might want to plumb in a gauge on that breather system and watch the pressures. 

[N-gin]

/quote]

I have the .030 cometic

Maybe try lowering your oil level 1/2 quart.       Coff 06

I already run it one notch from the bottom of the dipstick. this last time I know it was right in the middle of the crosshatch area and that was after warm sitting for a couple of minutes. I may try to lower it some more but this is a dyna it doesn't hold much to begin with.

Check the leakdown, just to make sure it's a venting thing, not a blowby thing?

oh man don't say that. I'll check, I have to leak down gauge, mine is in storage because of the move to Georgia. I do have a compression tester though not the same.

[N-gin]

How much oil are you pumping to the top of the motor?  Its either too much oil as the rpms come up.  Sumping preventing the oil from draining ( doubt that with a three stage pump) or its building blow by as the rpms go up.

With those big bores the piston skirts, or lack of become an issue.  Piston fit become critical.  If the skirt clearance loosens up you can get some rocking and loose the ring seal.  Might want to plumb in a gauge on that breather system and watch the pressures.

That's an idea about the gauge...
You made me think of something.
Do you guys think the breather tubes are too small? I bought the HPI external breather adapters and they have very small nipples. I did drill them a tad bigger cause they looked offley small to begin with. To put it to perspective I pushed on a 1/4 hard air line used for truck air brakes.

[FLDavetrain]

How much oil are you pumping to the top of the motor?  Its either too much oil as the rpms come up.  Sumping preventing the oil from draining ( doubt that with a three stage pump) or its building blow by as the rpms go up.

With those big bores the piston skirts, or lack of become an issue.  Piston fit become critical.  If the skirt clearance loosens up you can get some rocking and loose the ring seal.  Might want to plumb in a gauge on that breather system and watch the pressures.

That's an idea about the gauge...
You made me think of something.
Do you guys think the breather tubes are too small? I bought the HPI external breather adapters and they have very small nipples. I did drill them a tad bigger cause they looked offley small to begin with. To put it to perspective I pushed on a 1/4 hard air line used for truck air brakes.

Absolutely that could be the problem. Been there done that with issues surrounding the hpi external breathers. 1/4 inch hose is so far breathing better for my 124 dyna but if it shows stuffed up signs again I'll contact Jimmy for a different stand off and nipple size.

[Ajayrk]

*

[No Cents]

  I run 3/8" breather hoses on my 124 over to the catch can.
These bigger motors have to breath.
Have you noticed any addition crank pressure? Is the dip stick hard to get out once the engine is up to full running temp?

[attach=0,msg1296959]

[N-gin]

  I run 3/8" breather hoses on my 124 over to the catch can.
These bigger motors have to breath.
Have you noticed any addition crank pressure? Is the dip stick hard to get out once the engine is up to full running temp?

[attach=0,msg1296959]

Oil cap is tough to get to when hot due to exhaust routing.
These should have any pressure, right.
I haven't done this but with the old build when I had 3/8 air hose on the breather system I would have vacuum in the crankcase if I just run it shut it off and then pull the drain plug for the crankcase it would actually have vacuum. I did a video on YouTube about it. This new build I haven't noticed any vacuum in the engine I'll have to call HPI for sure.

[N-gin]

Okay I talked to Jimmy at HPI.
he said that he's got he's done a couple of breathers the stamp steel ones from the Harley dealership that were assembled incorrectly. These are new parts off the shelf so if anyone is experiencing this please check the orientation of your breather it may be backwards. I'll be opening up my engine and checking the breather orientation thanks guys for all your input I'll let you guys know what I find.

[Ohio HD]

Blow into the vent hose. If you can, then they're in backwards. If not, they're ok.

[BVHOG]

Okay I talked to Jimmy at HPI.
he said that he's got he's done a couple of breathers the stamp steel ones from the Harley dealership that were assembled incorrectly. These are new parts off the shelf so if anyone is experiencing this please check the orientation of your breather it may be backwards. I'll be opening up my engine and checking the breather orientation thanks guys for all your input I'll let you guys know what I find.

They are all assembled incorrectly when shipped from Harley, the flapper valve is in backwards. It bit me once and just bit another one of my customers a couple weeks back again.  But if this is the issue then I can't see how oil can get out of the breather system at all.

[1workinman]

How much oil are you pumping to the top of the motor?  Its either too much oil as the rpms come up.  Sumping preventing the oil from draining ( doubt that with a three stage pump) or its building blow by as the rpms go up.

With those big bores the piston skirts, or lack of become an issue.  Piston fit become critical.  If the skirt clearance loosens up you can get some rocking and loose the ring seal.  Might want to plumb in a gauge on that breather system and watch the pressures.

That's an idea about the gauge...
You made me think of something.
Do you guys think the breather tubes are too small? I bought the HPI external breather adapters and they have very small nipples. I did drill them a tad bigger cause they looked offley small to begin with. To put it to perspective I pushed on a 1/4 hard air line used for truck air brakes.

That what I run on by 12 street glide also . Not sure exactly the correct name for it. I made my fittings that screw into my heads by silver soldering the fitting together to make what I wanted and heated up the line and pressed them on the barb , added SS checks to them on . I added the breather that Ray did to his and also used the air line to those fittings also . Ran that line up with the SS check  and over to  the chain . My motor has around 5k on it and used very little . That line is black and really tough . I run my oil about 4 to 5 dots low on the fill

[N-gin]

This is the front cylinder

[N-gin]

Intake looks clean.
There was some oil residue on the intake but not behind the trottlebody. I'm thinking it was from the oil pouring out of the catch can and soaking the air filter
So it looks like it's put together correctly.
I'm stumped.
Oil level is one inch on dip stick. So it is a third the way up

[N-gin]

Is that gasket suppose the overhang like this?
That doesn't look right.

[dynabagger]

Blow-by? Have you done a leak down test?

[N-gin]

Not directly.
The catch can puffed very little out the filter.
I'll have to locate a gauge.

[pwmorris]

For sure, you have to start at zero, which means a leak down.
If all is good, get to work.

So this is a 120"? 117"?
11-1 CR or less?
Where are you venting this motor?
Are you running one way check valves on your venting?
Is oil tank vented?
Are heads vented? If so, where, how?
Have you dumped your crankcase to see how much oil is in there?
At 120" and up, and healthy comp, I would never just trust my stock internal breathing systems (especially those tiny drain holes) to solve my pressure/venting problems.

I run a quart low, but I spin mine up more than most.
The reason you don't see anything putting around town is that at moderate speed and gearing, the motor is not being tested under load.
Hard launches, hi rpm shifts, and hi speed freeway stuff exposes your weaknesses-and that bigger air/oil pressure must go somewhere, and must be addressed.
Breathe, breathe, breathe.....

[rredneckn2]

For sure, you have to start at zero, which means a leak down.
If all is good, get to work.

So this is a 120"? 117"?
11-1 CR or less?
Where are you venting this motor?
Are you running one way check valves on your venting?
Is oil tank vented?
Are heads vented? If so, where, how?
Have you dumped your crankcase to see how much oil is in there?
At 120" and up, and healthy comp, I would never just trust my stock internal breathing systems (especially those tiny drain holes) to solve my pressure/venting problems.

I run a quart low, but I spin mine up more than most.
The reason you don't see anything putting around town is that at moderate speed and gearing, the motor is not being tested under load.
Hard launches, hi rpm shifts, and hi speed freeway stuff exposes your weaknesses-and that bigger air/oil pressure must go somewhere, and must be addressed.
Breathe, breathe, breathe.....

PW just summed it up.

[Kllongbrake]

PW, what do the check valves on the breather hoses accomplish? Isn't the umbrella stopping any reverse airflow? 

[N-gin]

For sure, you have to start at zero, which means a leak down.
If all is good, get to work.

So this is a 120"? 117"?
11-1 CR or less?
Where are you venting this motor?
Are you running one way check valves on your venting?
Is oil tank vented?
Are heads vented? If so, where, how?
Have you dumped your crankcase to see how much oil is in there?
At 120" and up, and healthy comp, I would never just trust my stock internal breathing systems (especially those tiny drain holes) to solve my pressure/venting problems.

I run a quart low, but I spin mine up more than most.
The reason you don't see anything putting around town is that at moderate speed and gearing, the motor is not being tested under load.
Hard launches, hi rpm shifts, and hi speed freeway stuff exposes your weaknesses-and that bigger air/oil pressure must go somewhere, and must be addressed.
Breathe, breathe, breathe.....

Motor is a 120" with 4.375 stroke
Compression is close to 12:1 cranked 225 in Florida according to Wes B.
It is vented to a catch can located to the front of the bike attachched to the down tubes. About an inch or 2 above the breathers for the head. No check valves in the hoses. I have 2 separate hoses, one for each head. Hoses are hard line plastic 1/4 inch. I did drill the nipples on the HPinc breathers. Oil catch is vented at the top to atmosphere.

I'll drain the crank case.

One note/question:
If I was getting blow by wouldn't the oil be black?
It's still tan color with some hard miles, about 2000. Not a lot but maybe enough to turn it black if rings not seated.