Quick Question Oil Drain Plug...
Outstanding HDF Member
Joined: Oct 2009
Posts: 2,488
Likes: 30
From: Maryland near DC
my 08 streetbob (96 motor) came with pipe dope on the plug from the factory....as did my 11 flhrc...I wonder who knows better the folks here or the guys who built the bike/motor....
Outstanding HDF Member
Joined: Jan 2010
Posts: 2,916
Likes: 31
From: earth
A manufacturer would never use a shortcut trick on the assembly line to get a unit to pass QC inspection. Its not a matter of who knows better, yes they come from the factory with pipe dope on the threads of an O ring plug, but that doesn't make it right, and its funny the service manual says nothing in writing about using a secondary sealant, only to inspect the O ring and replace as necesssary. You could smear pipe dope on your oil filter sealing surface and that would still work too, but you would never do that because it adequately seals on the O ring and an additional sealant is not necessary.
Road Master
Joined: Mar 2010
Posts: 934
Likes: 54
From: SE Wisconsin
If I had to guess why the factory puts something on the threads of the o-ring plug, I would say its likely for lubricating and protecting the threads.
When two different metals are put together they could form a corrosion battery and could bond together.
Anti-seize, a little oil, or some grease would do here, so why not? There must be a reason why anti-seize is not used. Maybe due to the solid lubricating particles in anti-seize, and risk of getting some of it in the oil. Oil or grease, I would guess somewhere a plug has loosened up and fell out new motor warranty risk.
Then there is Teflon paste dummy proof, it lubricates and protects the threads, it helps hold like Loctite, and a little in the oil probably wont hurt either. Teflon paste is also used for sealing taper threads, so false assumptions are made and a dealer service monkey will glob it on and ignore the critical o-ring seal.
Most of us are quite satisfied with a little oil on the o-ring and threads when properly tightened.
When two different metals are put together they could form a corrosion battery and could bond together.
Anti-seize, a little oil, or some grease would do here, so why not? There must be a reason why anti-seize is not used. Maybe due to the solid lubricating particles in anti-seize, and risk of getting some of it in the oil. Oil or grease, I would guess somewhere a plug has loosened up and fell out new motor warranty risk.
Then there is Teflon paste dummy proof, it lubricates and protects the threads, it helps hold like Loctite, and a little in the oil probably wont hurt either. Teflon paste is also used for sealing taper threads, so false assumptions are made and a dealer service monkey will glob it on and ignore the critical o-ring seal.
Most of us are quite satisfied with a little oil on the o-ring and threads when properly tightened.
Outstanding HDF Member
Joined: Jan 2008
Posts: 3,328
Likes: 15
From: Pacific Northwest
This comes up constantly - just saw the same topic only last week.
The factory AND the dealers both use pipe dope/teflon tape. They are MORONS (and so is anyone else that does this).
If you have any HD dealer service your bike absolutely insist that there be no pipe dope (or tape) used on your drain plug.
If you find pipe dope on your plug clean it off with diesel fuel - it works the fastest. Get a new, properly sized o-ring that fits in the groove snugly. Lube it with some motor oil and tighten it up no more than 'snug'. No torque wrench necessary.
Pipe dope will push the o-ring out of it's groove and cause it to tear resulting in a leak. It also can and will lead to galling of those fine threads in your spendy aluminum cases.
The factory AND the dealers both use pipe dope/teflon tape. They are MORONS (and so is anyone else that does this).
If you have any HD dealer service your bike absolutely insist that there be no pipe dope (or tape) used on your drain plug.
If you find pipe dope on your plug clean it off with diesel fuel - it works the fastest. Get a new, properly sized o-ring that fits in the groove snugly. Lube it with some motor oil and tighten it up no more than 'snug'. No torque wrench necessary.
Pipe dope will push the o-ring out of it's groove and cause it to tear resulting in a leak. It also can and will lead to galling of those fine threads in your spendy aluminum cases.
Cruiser
Joined: Aug 2009
Posts: 142
Likes: 0
From: Colorado Springs
Update:
Exhaust mount bolts to Tranny where tight. there was a little excess oil in A/C so drained and refilled with only 3qts. wire's at front of crank case are sealed with hightemp silicone. Oil filter checked. No oil cooler on this bike...and it still leaks..So my only guess would be once again the inner primary seal
I'll let it go for the summer and keep an eye on the fluid level. its not low, neither was tranny. Next winter I'll plan a bigger project and do it then. Can't see spending $80. in parts and a whole day just for a small leak.
Exhaust mount bolts to Tranny where tight. there was a little excess oil in A/C so drained and refilled with only 3qts. wire's at front of crank case are sealed with hightemp silicone. Oil filter checked. No oil cooler on this bike...and it still leaks..So my only guess would be once again the inner primary seal
I'll let it go for the summer and keep an eye on the fluid level. its not low, neither was tranny. Next winter I'll plan a bigger project and do it then. Can't see spending $80. in parts and a whole day just for a small leak.
Extreme HDF Member
Joined: Dec 2010
Posts: 14,778
Likes: 69
From: Badlands of ND
The O ring will cost less than a dollar, and 3 quarts of oil are not that much either. Just change the oil and fix the plug.
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Road Warrior
Joined: Jun 2009
Posts: 1,943
Likes: 3
From: NYC
pump the oil out thru the filler. replace the oil ring, teflon, or what ever you think will work, refill the oil . Pep boys sells a basketball size pump that I use to pump out oil of bikes and cars I don't want to screw around with drain plugs on.
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