Problem with Air Cleaner External Breathing
What comes out the crankcase vent is mostly exhaust that went past the rings instead of out the exhaust port. Along with oil and water it picks up in it's travels through the crankcase. All internal combustion motors have at least some blow-by, no matter how good the ring seal. Minimal outflow from the crankcase vent indicates good ring seal. In these motors, it also indicates the check valves are working correctly, because the crankcases are variable volume and without check valves, you get an inhalation/exhalation thing going on.
Last edited by Midpegs; Mar 11, 2020 at 03:52 PM.
As said they equalize the pressure in the crank case as the pistons go up and down. What little in there gets mixed with condensation in the crank case and is expelled out the breathers. If you get bad rings the oil vapor will build up as blow by and that can become a problem. You would almost have to over fill the oil tank to the very top to be a problem Disregarding what you hear over the internet.
Correct ! That's what this thread is about . It is not about the CRANKCASE VENT which is tucked away behind the starter motor .
No , that's where the Rocker Boxes are vented . The crankcase vent is on top of the crankcase ( unsurprisingly ) somewhere behind the starter motor .
Road Warrior
Joined: Sep 2017
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From: over the mountain
You are 100 % incorrect. I believe you are talking about the transmission vent. The crank case vents out the rocker boxes. Do you think aswracing who is Hammer Peformance wouldn't know that.
As the pistons go up and down they create pressure in the crank case. To relieve this pressure its vented to the rocker boxes where it is metered out through the umbrella valves in the rocker boxes. They are designed to let air out but not lest it suck air back in.
As the pistons go up and down they create pressure in the crank case. To relieve this pressure its vented to the rocker boxes where it is metered out through the umbrella valves in the rocker boxes. They are designed to let air out but not lest it suck air back in.
Last edited by apache snow; Mar 11, 2020 at 04:12 PM.
You are 100 % incorrect. I believe you are talking about the transmission vent. The crank case vents out the rocker boxes. Do you think aswracing who is Hammer Peformance wouldn't know that.
As the pistons go up and down they create pressure in the crank case. To relieve this pressure its vented to the rocker boxes where it is metered out through the umbrella valves in the rocker boxes. They are designed to let air out but not lest it suck air back in.
As the pistons go up and down they create pressure in the crank case. To relieve this pressure its vented to the rocker boxes where it is metered out through the umbrella valves in the rocker boxes. They are designed to let air out but not lest it suck air back in.
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Road Warrior
Joined: Sep 2017
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From: over the mountain
Its OK You know now. Kick back and have a beer.