what's the third plug for?
Seasoned HDF Member
Joined: Jun 2006
Posts: 30,881
Likes: 32,991
From: King George, VA
If you can get ahold of a drawing of the oil pan, you will see a series of oil routing lines. The hole is used in the machining process for a horizontal oil line in the case. It can be used for an oil sending unit and may be a better place for it because it samples hotter oil than if you used the H-D recommended oil line tap.
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Road Master
Joined: Oct 2007
Posts: 1,028
Likes: 1
in the manual it says used in the machining process. it also shows the oil flowing right there so it makes it a good place for a sender
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Cruiser
Joined: Sep 2007
Posts: 157
Likes: 0
From: Port St. John, FL
OK looks like some confusion here. The one the poster os referring to is on the actual crankcase. the one where y'all are putting the sender is on the front of the Oil Pan (on Baggers). The crankcase plug is really not supposed to be removed and is there for machining purposes, also it would be sensless to put a sensor there as there really shouldn't be but a couple onces of oil in the actual case.
The only time you might want to remove that plug (and very carefully) would be to check for sumping in the motor due to a problem with the scavenging of the oil pump. Otherwise, leave it alone.
The only time you might want to remove that plug (and very carefully) would be to check for sumping in the motor due to a problem with the scavenging of the oil pump. Otherwise, leave it alone.