Primary leak
Primary leak
This is the first of what I'm sure will be many, many Evo questions :-)
My '96 FLHR has a leak coming from the drain plug on the primary.
I drained the primary, got a new plug, gooped the heck out of with teflon, then put everything back together. It helped quite a bit, but it's still marking its territory on the garage floor. About a teaspoon/week
I don't want to crank on the plug any more for fear of stripping the primary cover.
Should I just live with it as part of the "Evo Experience" or is there something else I should try?
Thanks guys...
My '96 FLHR has a leak coming from the drain plug on the primary.
I drained the primary, got a new plug, gooped the heck out of with teflon, then put everything back together. It helped quite a bit, but it's still marking its territory on the garage floor. About a teaspoon/week
I don't want to crank on the plug any more for fear of stripping the primary cover.
Should I just live with it as part of the "Evo Experience" or is there something else I should try?
Thanks guys...
Seasoned HDF Member
Joined: Aug 2007
Posts: 8,195
Likes: 3,085
From: NW AR
Are you sure it's from the drain plug and not from somewhere else dripping down to that point? Clean the entire area really well, then let it sit and watch. Common points for leaks are the gasket ring between the inner primary and the motor block, the seal around the transmission shaft, derby cover. Look for a very small crack at the plug area. With some teflon tape on the plug and snugged down reasonable, there should be no leak.
Thanks guys
Yea, I checked the primary cover bolts. The reason I am so set on it being the plug is the bulk of the moisture seems to be on the outside of the plug, along the lower part of the hole. That plus the fact that just cranking it down a bit slowed the leak quite a bit and replacing the plug and using the teflon seemed to slow it ever more. Still drippy though.
I cleaned it up real good, put about 60 miles on it and parked it in the garage with a can underneath the drain plug. I'm out of town for a week, so I'll take a closer look when I get home and see what I can see.
I'll let y'all know what I find out!
Yea, I checked the primary cover bolts. The reason I am so set on it being the plug is the bulk of the moisture seems to be on the outside of the plug, along the lower part of the hole. That plus the fact that just cranking it down a bit slowed the leak quite a bit and replacing the plug and using the teflon seemed to slow it ever more. Still drippy though.
I cleaned it up real good, put about 60 miles on it and parked it in the garage with a can underneath the drain plug. I'm out of town for a week, so I'll take a closer look when I get home and see what I can see.
I'll let y'all know what I find out!
Road Master
Joined: Apr 2009
Posts: 1,123
Likes: 43
From: NJ
Since you replaced the plug and gooped it up real good, could be that the outer primary is cracked. The thin metal between the plug hole and edge can crack if the plug gets over tightened and it's hard to see. You might also want to check the trans vent "J" tube, see if the end is a little on the wet side. It can mist the inner primary and it runs down and drips right off the primary plug.
Goog luck
D
Goog luck
D
Elite HDF Member
Joined: Sep 2007
Posts: 4,468
Likes: 12
From: Bluffton, South Carolina
Try some teflon tape instead of the paste. Put enough on so that when it's snug you have about 1/8" sticking out from the outer primary. Hope this helps, and look around the hole with a magnifying glass to see if it is cracked as mentioned previously.
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I'd always used the paste since that's what the Fix My Hog guy uses. I've never had a plug leak in any of my "96 motors. I'm game to try the tape.
I also have a gasket handy as the next level of fix if it comes to that.
Sure LOOKS like the plug, but I'll see what I can see when I get home next weekend.
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Seasoned HDF Member
Joined: Nov 2009
Posts: 15,705
Likes: 22,718
From: Farmington ,MS
Most any leak on the primary will drip off the plug...it is the low spot. Wash your primary very well and spray it with powder type deodorant...Arrid extra dry works well...crank it up and find out were the leak is coming from.
Intermediate
Joined: Apr 2010
Posts: 47
Likes: 0
From: Central Ohio
I may be wrong but i believe the drain plug for the primary is "pipe thread" to seal without anything. that being said over tightening can crack the primary case due to the tapered pipe thread.