HELP! Primary Cover Replacement issue
Seasoned HDF Member
Joined: Mar 2007
Posts: 66,948
Likes: 4,573
From: TOAK western branch
I don't remember exactly what the diameter of the hole plug is, but (from experience) I can tell you that you will need to seal the hole when the plug is installed. The primary belt's rotation will cause a positive pressure that will push fluid out around the plug unless it's sealed. And, replacing the primary cover is definitely a job that you can do yourself if you have the right size hex key (allen wrench) bits, and a diagram outlining the bolt tightening sequence and torque specs (which can be fudged a little on the loose side ... but over torquing in aluminum is bad news).
Cruiser
Joined: Nov 2013
Posts: 123
Likes: 1
From: Navarre Florida
If that's how it's supposed to work, it doesn't work well. I've had to seal primary hole plugs in 2008 and 2009 models (modified to have forward controls ... so I assume that the plugs were part of the forward control kits) that were weeping fluid around the plugs.
Cruiser
Joined: Nov 2013
Posts: 123
Likes: 1
From: Navarre Florida
I can vouch for one bike but not the other. I didn't do the forward control installs on either bike ... just trying to help friends out by fixing existing problems. But I did have the 2008 Dyna completely apart, so I'm fairly confident the vent line was good to go. Would the type of fluid used in the primary make a difference because of viscosity?
Seasoned HDF Member
Joined: Mar 2007
Posts: 66,948
Likes: 4,573
From: TOAK western branch
I'd say ATF would be the most likely to weep but my guess would be not using silicon sealent even though its not required. To many variables to speak to a specific situation without seeing first hand.
Cruiser
Joined: Nov 2013
Posts: 123
Likes: 1
From: Navarre Florida
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Tourer
Joined: Nov 2011
Posts: 377
Likes: 9
From: Mtl
Oh that damn primary mid controls hole. I swapped out my cover and had the same issue.
If you bought the cover from the dealer have them change it for the right one without the hole. There is a cap that comes with forward controls to cover it but it is only cosmetic.
I had a friend of mine who is a machinist plugged it up from the back. He tapped the whole and closed it permanently. Then I popped in the cap. My advise would be find a mechanic or machine shop and have them close it permanently.
My switchback is very modded so if out have any questions don"t be shy to ask. It is currently all torn down for my large winter project.
Here are some picks of the blacked out engine, you can see the plug in my primary cover.
If you bought the cover from the dealer have them change it for the right one without the hole. There is a cap that comes with forward controls to cover it but it is only cosmetic.
I had a friend of mine who is a machinist plugged it up from the back. He tapped the whole and closed it permanently. Then I popped in the cap. My advise would be find a mechanic or machine shop and have them close it permanently.
My switchback is very modded so if out have any questions don"t be shy to ask. It is currently all torn down for my large winter project.
Here are some picks of the blacked out engine, you can see the plug in my primary cover.
Last edited by Sticky4; Dec 31, 2013 at 06:35 AM.