I have a 2007 Road King that has a minor fluid leak. I bought the bike 3 years ago with 8700 miles, had 14,250 this spring, so I changed the oil, primary fluid and transmission fluid. The bike never dripped a single drop of oil until after the fluid change.

Fluid (2 or 3 drops) is dripping off the primary cover bolt just in front (toward the forks) of the primary fluid drain plug. When I first noticed it, I tightened the drain plug, and wiped off the drip. The drip came back, but the drain plug is dry.

I did some reading on the internet (with a grain of salt), and found quite a few posts about overfill transmission fluid coming out of the vent hose. I checked my tranny fluid level, and it was overfull.

I drained the fluid out so that with a cold engine, the level is just at the lower mark on the dipstick. I still have the drip, although it is sporadic. When it shows up, it is only after a ride. If I wipe it off, no more drip until the next ride, and on a few occassions, it hasn't dripped at all after a ride, only to show up again after the next ride. Sometimes it dosen't drip until overnight after the ride, sometimes it is within 15 minutes of shutting the engine off after a ride.

I can't seem to find where it is coming from, although the back side of the primary case has some fluid on it (but the front pully and the belt are bone dry). On a 2007, the vent hose is on the top of the transmission, correct ? If it is coming out of the vent, (the small candy cane shaped hose on top of the tranny), would the fluid only show up on the back and bottom of the primary case? Wouldn't it be all over the top of the transmission and primary under the candy cane hose ?

I will put it up on a lift first chance I have, but I am looking for thoughts. I read a lot about leaking transmission shaft seals, but if it was a seal, wouldn't it leak even when not ridden (in other words it would leak between rides) ? Mine only leaks after a ride.

Thanks

 

Could also be the seal where the shifter shaft comes out of the transmission which is very common. PITA to replace as it requires the removal of the primary.

I've have replaced a couple on my 08 RK over the years as well as a couple on my sons 06 RK

 

With the bike on the jiffy, oil can travel and the primary near the drain is a low point where it can gather...check the 2 bolts on the transmission cover that the exhaust hanger bracket attaches to. These come loose and leak trans fluid. Also the grommet where the stator wire comes out, left and front of the primary is a known weeping point.

 

Thanks, I will check those next, I'm done for tonight. I put the bike on the lift. the backside of the primary case, under the front pulley, is damp.

The pulley is dry, the belt is bone dry. There is a fin on the case, below the pulley that has fluid on the top surface, the fin is below the pulley.

It looks like the fluid is dripping onto the fun, and running down the back of the primary case, onto the lowest bolt in the primary cover.

The question is - dripping onto the fin from where. If it was seeping at the pulley shaft, the pulley would be wet with fluid, so would the belt, but they are both bone dry

 

Rebuilt my trans and the main seal leaked. It wasn't even dripping on the floor. But like yours it was traveling from the bolt Bose(you say fin) to the primary right behind plug. It was hard to see but behind the pulley was damp. It didn't get on the pulley just ran down the side of trans then across. Tour primary apart put Harley seal in instead of Baker & all is high & dry. You have to lay on your back and have a flash light to see it, better if on jack (that's how I seen it at first). Had a small rag setting on that boss for a couple hundred miles.

 

Check the wiring that comes from your stator and goes to the voltage regulator. The plug on the primary cover can leak primary oil and it will run down the front of the primary and drip from the bottom. Will only leak when riding.

 

I had a leak coming down the back side of the inner primary. I put red Belray oil in the transmission and dye in the primary to determine which was leaking. It was the inner primary seal which of course requires the removal of the inner primary. There is an excellent video on you tube about removal and replacement. While you have it off replace the shifter shaft seal and starter o-ring. Just requires minor wrenching skills with the right tools. Hope this helps.


Mike

 

I recently adjusted my clutch and afterward I had some drips on the floor. The oil had run down, collected around the primary drain plug bolt, and dripped onto the floor. I got a new derby cover gasket, changed it, no more drip. Did you reuse your gasket?

 

The stator wire grommet and exhaust support bolts are all dry. I used a new gasket on the derby cover.

The shifter shaft penetration through the backside of the inner primary is to the front side of the primary case "fin", and the damp spot on my primary case is directly under the front pulley, to the back side of the primary case "fin". I'm not sure a drip from the shifter shaft could get to the backside of the fin.

I believe it's either the transmission shaft seal where the main shaft exits the transmission - a leak here would have to travel the length of the shaft, hit the backside of the primary case, and drip down the primary case in order to replicate where I am seeing the damp spot on my primary. And how could this fluid travel the length of the shaft without spinning off the shaft and getting on the pulley and belt ?

Or it's the inner primary seal around the transmission shaft where it penetrates the primary case. I believe this is where my leak is.

 

If it's not behind the pulley on the wall of trans then it's the primary side. Sounds like it's one of those two, main or inner primary. So primary all has to come off either way. Then u can see if it's primary if not then pulley will have to come off too.