2004 FLSTF Oil Leak
Elite HDF Member
Joined: Aug 2008
Posts: 4,133
Likes: 125
From: Japan
Still not specific enough. That pic makes it look like its leaking from the swing arm. Where is the drip coming from on the bike and how much leaks after you ride?
My 2008 FB leaks from the same area. It usually drips from the primary drain plug and that's where I thought the leak was coming from originally, but it turns out that it is coming from above that area and trickling down to the lowest point, which happens to be the drain plug, and drips a lil puddle about the size of a quarter while it cools down. In my case, it's probably coming from the inner primary seal, tho i'm not 100% certain. I'll likely buy a primary gasket kit and replace 'em all this winter.
You'll probably need to wipe it down under there while it's cool, run it and get it up to temperature (ride it a bit if need be) and then get up in there with a flashlight to see whereabouts the leak is coming from...
My 2008 FB leaks from the same area. It usually drips from the primary drain plug and that's where I thought the leak was coming from originally, but it turns out that it is coming from above that area and trickling down to the lowest point, which happens to be the drain plug, and drips a lil puddle about the size of a quarter while it cools down. In my case, it's probably coming from the inner primary seal, tho i'm not 100% certain. I'll likely buy a primary gasket kit and replace 'em all this winter.
You'll probably need to wipe it down under there while it's cool, run it and get it up to temperature (ride it a bit if need be) and then get up in there with a flashlight to see whereabouts the leak is coming from...
Road Captain
Joined: May 2014
Posts: 648
Likes: 35
From: San Diego
Is that oil or gas? I know the gas vent hose on my 06 Deluxe starts from the front of the tank and ends back at the right side of the swing arm. Does it coincide with you just filling up the tank?
Oil as far as I know . I'm haven't smelled any gas yes . Wiped underneath it and took it for a long ride yesterday. Kept checking it and only noticed a drip , nothing like before . I did fill it with gas while I was out .
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Elite HDF Member
Joined: Aug 2008
Posts: 4,133
Likes: 125
From: Japan
The oil is getting blown up onto your belt from the wind while riding. Same thing happens to mine...
Still hard to tell from those pics without a complete wipe down (and perhaps without cleaning that muck off the bottom of your motor with some brake cleaner), but I'm going to take a stab and say that leak looks to be coming from the transmission, just going off the general area of the leak. Leaking oil looks fairly clean, which could also indicate tranny oil...
Still hard to tell from those pics without a complete wipe down (and perhaps without cleaning that muck off the bottom of your motor with some brake cleaner), but I'm going to take a stab and say that leak looks to be coming from the transmission, just going off the general area of the leak. Leaking oil looks fairly clean, which could also indicate tranny oil...
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Ultimate HDF Member
Joined: Jul 2007
Posts: 5,577
Likes: 138
From: South of Dallas Area, Texas
Pull the stick on the transmission and check the level. Easy enough to do. If its low, start looking at the trans.
Hosing down the gunk on the bottom as stated is a good place to start also.
Hosing down the gunk on the bottom as stated is a good place to start also.
Seasoned HDF Member
Joined: Nov 2004
Posts: 8,129
Likes: 1,981
From: Ottawa, CANADA
Reaper had a similar leak, and it turned out to be the transmission mainshaft seal. To replace it requires removing the entire primary.
When I replaced mine, I also replaced all the related seals: shifter shaft seal, inner primary bearing seal, mainshaft 5th gear seal, starter shaft seal. I also replaced the 2 piece inner primary bearing with an All ***** one piece unit. The reason for replacing the bearing is that the stock inner race, pressed onto the mainshaft had "walked" in toward the transmission case, and would have started leaking eventually, even with a new seal installed.
It's not a super difficult job, but it's time consuming and some special tools are needed, so I hope that's not your leak.
Cheers!
When I replaced mine, I also replaced all the related seals: shifter shaft seal, inner primary bearing seal, mainshaft 5th gear seal, starter shaft seal. I also replaced the 2 piece inner primary bearing with an All ***** one piece unit. The reason for replacing the bearing is that the stock inner race, pressed onto the mainshaft had "walked" in toward the transmission case, and would have started leaking eventually, even with a new seal installed.
It's not a super difficult job, but it's time consuming and some special tools are needed, so I hope that's not your leak.
Cheers!
Last edited by Clammy; Sep 16, 2016 at 08:46 AM.