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Primary Vent

03ultra45385

Active Member
After replacing some parts in my primary and now that it is closed up I don't remember seeing any form of venting. Engine and transmition are vented, but how is the primary case vented. It gets hot, the oil and air in there gets hot and the air expands when it does. I figure it should be vented like the transmission. Just wondering.
 
After replacing some parts in my primary and now that it is closed up I don't remember seeing any form of venting. Engine and transmition are vented, but how is the primary case vented. It gets hot, the oil and air in there gets hot and the air expands when it does. I figure it should be vented like the transmission. Just wondering.

The Primary is not a pressurized system but rather an oil splash system like the tranny where the lube is slung around by the gears, sprockets, chain, etc. The primary can vent through the pushrod to the tranny. But neither is under pressure.

TQ
 
No vents on closed primaries, no need for it, belt primaries need venting because of the heat and no oil:s
 
I just had the primary off my friends 07 super glide and found that the vent was part of the primary cover,There is a machinrd hole in the inner cover that just goes to atmospher,cadt into the outer cover was a hallow stand off that connects to the hole in inner cover,there is a gasket taht gose inbetween them, also cast into the outer cover was a small stand off with a cup shaped cap that would keep oil out but let air flow and there was a passage inside outer cover rhat connected the two stand offs. Did yours have thosein the cover,I just gused they would all be simmular.
 
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