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Okay I have an 87 FLH and I have a hypercharger on it that is bolted to the heads there's no vent off the head and there is a filter hanging down below which goes to a hose to the lower part of the case I also have a 99 Softail that has no lower vent coming off the case no hanging filter and has vents coming off the heads which feed the front to the back and then into the back of the car plate stage one my question is when the 87 sits in the sump comes out it comes out the floor vent that hangs below when the 99 sits and I take it out I get oil on rear pipe and front of the oil tank from the wind.
Is the 87 an earlier motor vented correctly and the 99 a later model with no vent below vented proper ?
Both do the same thing right just different ways ? 99 from back of carb 99 from front 87 from back of carb Rear of case on 87
Yep- both are vented properly. When the 87 sits- gravity pulls oil out of the tank- past the check ball in the oil pump- and into the crankcase. When you start it- it blows that oil in the crankcase out the breather vent. My 92 did that too in the spring every year. The head breathers in the 99 do the same thing.
They are 2 different head and rocker box designs.
Same difference!
When either a filter or a screen gets dirty it makes it harder for the motor to breath out through that line.
Unless you are seriously OCD and clean that filter or screen a lot then the best thing you can do is remove it and let the motor breath like it wants to.
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Case vent
