Normal Blowby

[TFaoro]

This question gets asked a lot here, so I figured I'd take a video. Right now this engine has between 11,000 and 12,000 miles on it, and YES it has some blowby just like all engines do. My point being don't be freaked out by a little bit of blowby  

(Engine at 190* after a 40 mile drive)

 

[Mopar1973Man]

 

[dodgedieselnewbie]

Since I found and fixed a vacuum leak.. mine looks "normal" once again.

It was rising above my cab.. which didn't seem too normal.. to me ;-)

 

[Buzzinhalfdozen]

So if you were running a steady 2,500ish rpm and 10-15 psi for about 90 minutes, would you be alarmed about pushing some oil out around the oil cap? Enough to coat that half of the valve cover front to back. 

[TFaoro]

Thanks @Mopar1973Man! I just wanted to get a "low mile engine" video  

55 minutes ago, dodgedieselnewbie said:

Since I found and fixed a vacuum leak.. mine looks "normal" once again.

It was rising above my cab.. which didn't seem too normal.. to me ;-)

Hey I said SOME was normal. It's also hard to tell just how much is coming out when you're not looking directly at the breather. Good thing you got the vacuum leak fixed though.

28 minutes ago, Buzzinhalfdozen said:

So if you were running a steady 2,500ish rpm and 10-15 psi for about 90 minutes, would you be alarmed about pushing some oil out around the oil cap? Enough to coat that half of the valve cover front to back. 

It would be a little concerning but I'd start with checking for vacuum leaks and go from there. Testing things is cheap compared to a motor.

[Mopar1973Man]

43 minutes ago, TFaoro said:

So if you were running a steady 2,500ish rpm and 10-15 psi for about 90 minutes, would you be alarmed about pushing some oil out around the oil cap?

Being that like running 85 MPH on the interstate. I would be concerned. I would for sure be looking at the vacuum pump and vacuum lines as well as doing a compression test.

@TFaoro Even with low miles you still seem to straight stream of vapor with some force. Where mine is more of drifty vapor. This might have something to do with how your engine was rebuilt. (Cam, compression ratio, etc.)

 

[dodgedieselnewbie]

Since I fixed the vacuum leak.. there is a "tin like" sounding vibration coming from under the dash.. between the glovebox and cup holder. It's not constant but does make the noise under curtain light acceleration. Is the heater box under there?

[TFaoro]

8 hours ago, Mopar1973Man said:

Even with low miles you still seem to straight stream of vapor with some force. Where mine is more of drifty vapor. This might have something to do with how your engine was rebuilt. (Cam, compression ratio, etc.)

You're correct. Ring gaps, cylinder bores, etc. are all let's say "not stock" because it was built for higher performance. The point still stands though  

Can you get a video with the camera pointing straight at the tube? I think your tube ID is larger than mine as well.

4 hours ago, dodgedieselnewbie said:

Since I fixed the vacuum leak.. there is a "tin like" sounding vibration coming from under the dash.. between the glovebox and cup holder. It's not constant but does make the noise under curtain light acceleration. Is the heater box under there?

Could it be one of the actuators now that it's getting vacuum? Try all the different settings on the HVAC and see if it stays the same or not.

[Mopar1973Man]

They always said in the racing world that a slight crankcase vacuum is best it lets nature pull the piston back down. So if you capturing pressure in the crankcase in might be a good idea to increase the pipe size to vent more. There was an old article about using a one way check valve and inserting the crankcase vent into the exhaust stream creating that mild crankcase vacuum.

[TFaoro]

20 minutes ago, Mopar1973Man said:

They always said in the racing world that a slight crankcase vacuum is best it lets nature pull the piston back down. So if you capturing pressure in the crankcase in might be a good idea to increase the pipe size to vent more. There was an old article about using a one way check valve and inserting the crankcase vent into the exhaust stream creating that mild crankcase vacuum.

That's why she's got two vents! (Original and tappet cover)

[Mopar1973Man]

...and still blowing that much wow. Modified vs. stock...

[TFaoro]

10 minutes ago, Mopar1973Man said:

...and still blowing that much wow. Modified vs. stock...

You can see the two tubes next to each other in the video. Not much comes out the tappet cover breather though. Almost all from the front cover.

[Mopar1973Man]

Is the tappet cover plugged up?

[TFaoro]

Nope, it's wide open. I could see vapors coming out of it when the front breather was in a different location. I'm guessing that's just the path of least resistance.