gearbox oil leak : V-Twin Forum: Harley Davidson Forums

wanna ride · 05-10-2009, 05:02 PM

02 WG
I noticed even last year a drip everyonce in a while off my primary inner cover right below the clutch and today after an 80 mile outing decided to put the bike on the jack stand, I was able to lay down under the bike and with a brite flashlite I think I found the leak, it seems to be coming from the shifter arm which is of course part of gear box. I checked the oil in the gear box while bike was on the jack and the way I checked it which was to not thread it in but just seat it on the lip showed on the add mark.
So two part question do you's check gear oil by screwing in dip stick until it bottoms out or the way I described by just letting dip stick sit on the top of the threads?
Next question is it common for shifter link shaft to leak where it comes out of gearbox and is this a major job to replace seal?
I didn't see where any oil was getting on front sprocket or belt.
Another thought, if it is the shifter shaft seal wouldn't it be above the oil level, except possibly when on the side stand ?

TXCHOP · 05-10-2009, 07:55 PM

It sounds like you checked the oil level correctly, just sitting on the threads.
Shifter shaft seal leaks are probably the most common oil leaks on twin cams.
Its kind of a big job to replace as the enitre inner/outer primary has to come off. If you have it off, replace all the seals while your in there.
I would also suggest a cometic seal for the shifter shaft. It seems to work a little better than the hd.

They leak from just being a bad design. Their is a tube at the other end of that seal that just collects oil and it doesn't have anywhere to go.

wanna ride · 05-10-2009, 08:46 PM

Thanks for response, I filled gearbox up again as per manual instuctions and your reassurance. I'm thinking the only time the seal is leaking is probably when its on the side stand, especially with the lean it has. I took a closer look and now see where oil has gotten on the top of the belt in places, although only on outter side.
Are there any special tools I will need to get as far in as the shifter shaft or alternatives to getting past needing tools?