Stripped threads on outer primary.
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Road Master
Joined: May 2012
Posts: 910
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From: Elk Mound, WI
Stripped threads on outer primary.
Ran across a small leak on my 2012 Ultra yesterday. Looked like the outer primary gasket was the culprit. Stopped and grabbed a new one and set out to install. Not a big deal type of job. Anyway, I put the outer primary back on and threaded all the bolts in finger tight. Then grabbed my socket and just snugged them up. This part is important.... When I say I snugged them up all I did was complete threading them in until things touched. I did not used any force. Grabbed my inch pound torque wrench and set it to 150 in lbs as per the manual. Using the order identified in the manual began torquing them appropriately. I got to number 6 (see pic) and with hardly any pressure she just spun. Damn it!! All the rest of the bolts responded as expected but number 6 is definitely stripped. Not the bolt threads, the hole. If you look at this one on your bike, the threads are in the lower engine case, not the inner primary.
How can I fix this? Considering how the primary works and since the fluid stays low to lube the chain, I don't really think I'm in danger of it leaking, especially with the surrounding bolts tightened to spec. That said, I still want to fix it. Believe it or not, this is the first stripped bolt hole I've had to deal with. Advice is appreciated.
How can I fix this? Considering how the primary works and since the fluid stays low to lube the chain, I don't really think I'm in danger of it leaking, especially with the surrounding bolts tightened to spec. That said, I still want to fix it. Believe it or not, this is the first stripped bolt hole I've had to deal with. Advice is appreciated.
Road Master
Joined: Mar 2012
Posts: 986
Likes: 948
From: Ohio
The #6 bolt is a long one of four that screw into the motor case. So you will need to remove the inner and outer primary to look at the damages and decide on the course of action. Most likely a heli-coil will fix it.
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Road Master
Joined: May 2012
Posts: 910
Likes: 115
From: Elk Mound, WI
Thanks guys. I figured something like that would be the overall fix but I was hoping for an option to maybe get me by until I NEED to pull the inner primary off. It's not that I haven't done it before, it's just a job and something id rather mess with in the HOT Phoenix summer.
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Joined: Feb 2007
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From:
Thanks guys. I figured something like that would be the overall fix but I was hoping for an option to maybe get me by until I NEED to pull the inner primary off. It's not that I haven't done it before, it's just a job and something id rather mess with in the HOT Phoenix summer.
Many times the factory will thread holes deeper than bolt.
For example if hole continues for 0.5 inches more then just find or cut a bolt to just 1/4 inch longer than current bolt.
Last edited by im; Nov 16, 2025 at 07:44 AM.
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,310
Likes: 6,328
From: Honah Lee
Ran across a small leak on my 2012 Ultra yesterday. Looked like the outer primary gasket was the culprit. Stopped and grabbed a new one and set out to install. Not a big deal type of job. Anyway, I put the outer primary back on and threaded all the bolts in finger tight. Then grabbed my socket and just snugged them up. This part is important.... When I say I snugged them up all I did was complete threading them in until things touched. I did not used any force. Grabbed my inch pound torque wrench and set it to 150 in lbs as per the manual. Using the order identified in the manual began torquing them appropriately. I got to number 6 (see pic) and with hardly any pressure she just spun. Damn it!! All the rest of the bolts responded as expected but number 6 is definitely stripped. Not the bolt threads, the hole. If you look at this one on your bike, the threads are in the lower engine case, not the inner primary.
How can I fix this? Considering how the primary works and since the fluid stays low to lube the chain, I don't really think I'm in danger of it leaking, especially with the surrounding bolts tightened to spec. That said, I still want to fix it. Believe it or not, this is the first stripped bolt hole I've had to deal with. Advice is appreciated.
How can I fix this? Considering how the primary works and since the fluid stays low to lube the chain, I don't really think I'm in danger of it leaking, especially with the surrounding bolts tightened to spec. That said, I still want to fix it. Believe it or not, this is the first stripped bolt hole I've had to deal with. Advice is appreciated.
Didn't work on an intake manifold on another tread recently.
Try running in a bottom tap to clear thread and get it threaded to bottom of hole. Be gentle.
Then run a long threaded bolt in it to the bottom. Mark the length so a cap nut will tighten but not bottom .
Screw it out and use a hacksaw to make your all thread stud. I also saw a screw driver slot in it. Snug it in.
Now try it with the cap nut.
I personally don't use a torque wrench on small fastners in aluminum. When there wet with oil, spec is way too much.
I put a thin film of black RTV on gasket. Snung them all in. Then in proper order, snug them lightly with T handle socket between my fingers.
I let RTV that's about size of a small rubber band dry and it will just sheer off when you push it back toward engine.
First heat cycle, I recheck.
Worth a try.
PS.. Permatex Ultra Black RTV. Just a film put down on gasket on piece of clean cardboard. Not a layer. And use Harley's V shaped gasket. And let it dry before removing that band, that maybe comes out, or you will make a mess.
That little RTV fills any little scratches in cover and provides a long time no leak job. The 04 I gave to my son is still dry and been years since it was apart.
When everything is hot, there a lot of movement in those long aluminum parts.
Last edited by Jackie Paper; Nov 16, 2025 at 08:18 AM.
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Thread Starter
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Road Master
Joined: May 2012
Posts: 910
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From: Elk Mound, WI
Originally Posted by im
You can remove bolt and stick something in hole to measure thread depth.
Many times the factory will thread holes deeper than bolt.
For example if hole continues for 0.5 inches more then just find or cut a bolt to just 1/4 inch longer than current bolt.
Many times the factory will thread holes deeper than bolt.
For example if hole continues for 0.5 inches more then just find or cut a bolt to just 1/4 inch longer than current bolt.
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From: Near Yosemite
Be interesting to see one and how much they cost.
Seasoned HDF Member
Joined: Mar 2010
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From: Honah Lee
The tap is called a nut tap. You're probably not going to find that cheap. I see one for $15 but most are $70 ...
Just put a notch in a good bolt and clean thread.
I have a few fine thread nut taps.. One is 5.5 long but it's 5/16 -24 Fine thread.,
The 1/4-20 I have is 5". But it has a lot of chamfer designed to make long stand off nuts on a turret lathe and not break. Didn't work. One of the first jobs I worked with engineering to change a DWG. I ask why we couldn't just tap each end. They said sure..
?? 
. If that helps.Some of my tools go back 50+ years in my career.
Last edited by Jackie Paper; Nov 16, 2025 at 03:08 PM.