Primary oil leak
- Thread starter SoCalEzWider
- Start date
As they say, "if at first you don't succeed, ..."
Congrats, and hope it holds for ya. Keep an eye on the bottom of the inner primary case for wet/oily looking lines usually running across the case on the clutch side or slightly forward. But with the TC, I do not expect there to be enough flexing for any cracks to develop.
TQ
Congrats, and hope it holds for ya. Keep an eye on the bottom of the inner primary case for wet/oily looking lines usually running across the case on the clutch side or slightly forward. But with the TC, I do not expect there to be enough flexing for any cracks to develop.
TQ
SoCalEzWider
Member
update: I got a couple of good rides on it,(total of about 400 miles). So far so good. No signs of any leaking, or cracks in the inner primary. It looks like its going to hold. Thanks again for all the helpful suggestions.
Ez
Ez
I have had many leaks from primary case. (1998 Dyna-80000 KM)
The first one was the result of a wear (probably)of the sealing ring. The oil level increased in the crank case !!! and dramatically decreased in the primary case. Since I have replaced the ring, the crank level became normal.
The second issue appeared after I have removed the inner pimary case (change the belt). I had noticed that the primary level decreased.The leaks came from the bolts of the inner part. I Filled ALL the bolts holes with SPECIAL silicone before screwing again according to the good torque and waiting one day before re-filling the primary. Now All is ok.
So pay attention to the inner orings , the gasket and the cork-bolt.
The first one was the result of a wear (probably)of the sealing ring. The oil level increased in the crank case !!! and dramatically decreased in the primary case. Since I have replaced the ring, the crank level became normal.
The second issue appeared after I have removed the inner pimary case (change the belt). I had noticed that the primary level decreased.The leaks came from the bolts of the inner part. I Filled ALL the bolts holes with SPECIAL silicone before screwing again according to the good torque and waiting one day before re-filling the primary. Now All is ok.
So pay attention to the inner orings , the gasket and the cork-bolt.
I just read the entire thread and didn't hear anyone tell you to look for a crack, I used to build HMMWV motors and we used spray on crack detector chemicals, pretty straight forward. Spray on a developer let it dry then a penetrant that would show us those hairline cracks that were naked to our tired eyes. I did like Bud's suggestion for the leak detector kit but I am confident the crack detector chemicals will cost less than the UV kit he suggests and it sounds like you know where the oil is coming from just not why it's coming from there. The spray on detector can get into some pretty tight areas if applied patiently.
mitchellsell
Member
I am having the same problem. Changed the primary chain case gaskets and used RTV silicone, and the RTV means Room Temperature Vulcanization so the last time I did it I did not ride the bike for the rest of the winter and in fact did not put back chaincase oil.
No leaks while the bike was sitting flat using tie-downs but in the spring as soon as I put the bike on the kick stand it started to leak again. The leak is a very clean looking oil and definitely not coming from the engine oil.
Somebody said it might need a new main seal on the transmission since the bike would not leak from there unless it was put on the kick stand which makes the bike lean over and would let transmission fluid leak.
Still not sure what it is because the dripping oil looks so clean like Harley Motor Oil and I am guessing Transmission fluid looks different but I am going to check that out using the dip stick.
Regarding my earlier reply, transmission fluid and primary chain case fluid are exactly the same AND when new and clean they are the same color as engine oil
No leaks while the bike was sitting flat using tie-downs but in the spring as soon as I put the bike on the kick stand it started to leak again. The leak is a very clean looking oil and definitely not coming from the engine oil.
Somebody said it might need a new main seal on the transmission since the bike would not leak from there unless it was put on the kick stand which makes the bike lean over and would let transmission fluid leak.
Still not sure what it is because the dripping oil looks so clean like Harley Motor Oil and I am guessing Transmission fluid looks different but I am going to check that out using the dip stick.
Regarding my earlier reply, transmission fluid and primary chain case fluid are exactly the same AND when new and clean they are the same color as engine oil
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Shouldn't be the same fluid in these two different applications. Primary should have Formula +, Spectro Primary, or equivalent. Tranny should have a full synthetic GL5 75W-90 (minimum) gear lube. If you have the 6-spd, I suggest the Spectro 6-spd transmission gear lube.
The primary fluid will dirty up fast. The tranny fluid will retain its original color.
Before tearing everything up, make sure that the leak you are seeing is not the tranny vent tube blowing tranny lube mist on the inside surface of the inner primary case. See here:
Primary Oil Leak - Harley Davidson Community
TQ