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Primary oil leak

Got an 05 WG that I can't seem to get a leak from the inner primary case to seal. The leak is from the lower rear bolt that passes thru the inner primary to the trans case. There are no seals or gaskets for this bolt (even though its the only bolt in the primary that is submerged in the oil). The sevice manual only says to silicone all mating surfaces. I have replaced every bolt, locking tab, seal (trans, jackshaft,main) but it still leaked. I then replaced the inner primary, thinkig maybe the old one might be warped, and still leaked. I tried putting a nylon washer to seal the bolt from the inside, no joy. I then tried putting a gasket where the primary mates to the trans, again no joy. I have loaded the freakin hole the bolt passes through with silicone, and used teflon tape on the threads, and it still leaks. Oh yeah I'm 100% sure about where the oil is coming from...It's the only wet spot I can find when I tear it down (today I had the thing apart 3 times). Anyone got a suggestion or two? I'm gettin sick of cleaning the oil off the rear of the bike everytime I ride it
 
Try some Copper Coat gasket sealant if you can find it, a "old school" mechanics fix....may be hard to find, but it works.
 
Easy,

These kind of problems suck to the point where you want to pull your hair out and do damage to the bike.

The book says to use RTV or similar around the bolt holes on the trans where the inner primary mates. It also says to apply RTV to the threads of those same bolts when you install. I am sure you have done that, right? Still leaking?

You said you replaced the inner primary, so that eliminates that as a potential to leak from a hairline crack at the bottom.

You are using a new large o-ring seal each time? Now a-days they seem to be blue with a tab on them to hold on to.

I would go back to square one and make sure that everything is spankin clean. Use new o-ring and gasket. Then reinstall everything by the book in sequence using that black high temp RTV from the auto shop. Make sure that the bolt threads are clean and dry (no oil) and apply RTV liberally as indicated in the book making sure that the bolt threads get a big wad all the way around the threads for the entire length of thread. Use plenty. Snug everything up using a torque wrench staging up to the max. listed in the book for each bolt. Let the bike sit for a bit after you are done. Then put the fluids back in and see how it is going. Hard to wait, but if it stops leaking it is worth it.

Good luck.

TQ
 
Silent, I remeber Copper Coat...Haven't seen that stuff in years,but would be worth a shot if I can find some. Thx. TQ, I pretty much have done everything have suggested. I put the [EDIT] thing back together last night (used all new gaskets again...) per specs. I let it sit overnight and am getting ready to go put the oil in it now. If it still leaks I'm gunna dump it in my local Harley dealers lap and tell em not to call me till the leak is fixed. Pretty much at my wits end. Thx.

http://www.hdtimeline.com/announcements_news_and_motions/9510-a_friendly_reminder.html
 
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Just a thought, is there a chance that the cover is "warped" somehow and not letting the surfaces mate up flush? Use a good straight edge on the surfaces and slide a feeler gauge (one of the thinest blades) under it and see if there are "lose" areas under the straght edge.....
 
Checked both surfaces ie...trans case and inner primary for flatness with a machinist ruler edge and a feeler gauge. Both are flat as can be. Yep, checked the shifter for leaks too, but no leak there. Besides the oil thats leaking is pristine clean. I'm due for a fluid change,motor and trans oil are a might bit dirty right now. Each time I have torn it down I have cleaned it up with spray brake cleaner to remove any and all oil residue. Everytime the only spot with oil is the lower casting on the trans case.
 
You might try to coat one surfaces with some machinest blue and mate them while still fresh and look for "gaps" in the "print" it leaves......
 
One other thing see if you can get the Dye they use to check for oil leaks at a autostore.. Dye + ultra violet light will take ya right back to the leak
 
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