Recently I noticed a oil leak coming from the primary outside cover so I decided to investigate.

Took my trusty Torque wrench and proceeded to torque the bolts to specifications.

Lo and behold one of them would not torque no matter how much I tried. (The one just forward of the drain hole).

Removed the outer primary cover and discovered the hole in question had a Heli-coil imbedded in it. The Heli-coil was protruding from the hole and I pulled it out with my fingers indicating it was not properly installed. Further inspection shows the hole in the case was slightly oversized for the Heli-Coil. It was the correct Heli-Coil (1/4 by 20) but the case hole was a little to large.

Looks like the case hole was drilled a little to large or was reamed out incorrectly.

I was able to get a new Heli-Coil installed and it seems to be holding, at least it torqued down to the proper torque(84-105 psi).



BUT it is still dripping just ever so slightly. A couple hour ride will show a light coating of oil on the finger if run along the bottom of the primary cover near the oil drain plug.



SO is there a way to repair that hole in the case so it is not so large? I suspect the oil is dripping past the screw.

I thought about putting a second Heli-Coil in it but there is insufficient material around the rim of the hole to screw it into. Somehow I need to build up the hole so it is not so large but I have no idea on how to do this.



I thought about filling the case hole with J-B Weld then re-tapping the hole to fit but am uncertain if this will work or not.



I have the necessary supplies and tools to perform the surgery except the tools and expertise necessary to remove the case so it will have to be done while still installed on the bike.



Any comments would be appreciated.



Regards,



John

 

Try a timesert? I believe they are a bit larger OD than helicoils.

Or clean, jb weld, use the cover as a guide to drill, tap to proper size.

 

Maybe a new gasket with some sealer around the area.

 

The right way would be to get a new inner primary or take it off,have it welded then drilled and tapped. I understand it's riding season and you don't want any down time. The jb-weld fix might work...i know I'd be thinking about it every time I rode though. Sounds like a new gasket and some sealer along the bottom mating surface will do the trick until you can fix it right.

 

that hole may go all the way through, some of the primary holes do. if so ,you could put longer bolt in and a nut on the back side. don't drill it, to make it go through.
check clearance of bolt and nut.

 

New inner primary would be the way to go, the problem with trying to weld & drill the inner primary is the metallurgy - its porous and a dirty type of metal to weld (like pot metal) - the oil has been penetrating that metal for years & attempting to weld it......well good luck. Just put a good sealer on it & ride until the weather is crap & replace it.

 

Thanks guys. Bolt does not go through. Gasket is new. I guess I will try a Time-Sert to see if it holds better.

The gasket is brand new but has been sitting around the garage for a year or so. It may have been compromised so just for the hell of it I may try a new gasket

 

u could tap it one size up if the time sert doesn't work.