O ring that goes on drain bolt.
Cruiser
Joined: Mar 2010
Posts: 118
Likes: 0
From: NE Ohio
On the Heritage, the primary o-ring is smaller.
Outstanding HDF Member
Joined: Oct 2006
Posts: 2,179
Likes: 1
From: Southern California
[quote=Mr. Lucky;7499659]The correct O-ring size is #41 (9/16" OD x 7/16" ID), available at any hardware store. All the fluid plugs use the same size.[/quote]
My Primary drain plug O ring is smaller than my Trans and my Oil drain plug O-rings...
My Primary drain plug O ring is smaller than my Trans and my Oil drain plug O-rings...
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,420
Likes: 6,367
From: Honah Lee
Primary
[quote=Soft06;7505017]The primary on some 04's like mine are tapered pipe plug dry seal designed to not require Teflon tape or a sealer (nptf). The 9/16 x 7/16 standard o-ring at the dealer is black buna-n designed for oil for the transmission and oil. Any standard black o-ring from the auto-parts stores will be buna-n. The bolt it fits on and screws into is an ms fitting. The o-ring is actual going up into a angle seat. If this fitting has not been damaged you should use a new o-ring at least ever other time and not use sealer. The fitting is deigned for the washer face of the bolt to go metal to metal with the fitting so as to stay tight. Remember, a standard 9/16x7/16 o-ring is .07 diameter cross section. Also does no harm in using sealer on nptf. Unless you have measuring tools it would be best to get it from Harley dealer in my opinion. FP, do not use an o-ring that is tool large. It will not go down into taper and tend to act more like a flat seal and unless you use a sealer on threads the bolt just may leak or worst yet vibrate out.
Last edited by Jackie Paper; Sep 14, 2018 at 10:27 AM.
Banned
Joined: Sep 2009
Posts: 7,580
Likes: 7
From: The Internet (& Dyer, Indiana)
[quote=grf000;7506247]
The primary on some 04's like mine are tapered pipe plug dry seal designed to not require Teflon tape or a sealer (nptf). The 9/16 x 7/16 standard o-ring at the dealer is black buna-n designed for oil for the transmission and oil. Any standard black o-ring from the auto-parts stores will be buna-n. The bolt it fits on and screws into is an ms fitting. The o-ring is actual going up into a angle seat. If this fitting has not been damaged you should use a new o-ring at least ever other time and not use sealer. The fitting is deigned for the washer face of the bolt to go metal to metal with the fitting so as to stay tight.
"Don't require teflon" doesn't mean you can't benefit from it.
One benny is that you can go soft on the torque without worrying about it coming loose (teflon paste, not tape). Tapered threads when overtightened can ruin your day.
As I said earlier, my o-ring has to be worn to the point of falling off, before I even bother replacing it. The teflon is doing the work on my bike, and all my cars. Many years have gone by without issue.
The primary on some 04's like mine are tapered pipe plug dry seal designed to not require Teflon tape or a sealer (nptf). The 9/16 x 7/16 standard o-ring at the dealer is black buna-n designed for oil for the transmission and oil. Any standard black o-ring from the auto-parts stores will be buna-n. The bolt it fits on and screws into is an ms fitting. The o-ring is actual going up into a angle seat. If this fitting has not been damaged you should use a new o-ring at least ever other time and not use sealer. The fitting is deigned for the washer face of the bolt to go metal to metal with the fitting so as to stay tight.
One benny is that you can go soft on the torque without worrying about it coming loose (teflon paste, not tape). Tapered threads when overtightened can ruin your day.
As I said earlier, my o-ring has to be worn to the point of falling off, before I even bother replacing it. The teflon is doing the work on my bike, and all my cars. Many years have gone by without issue.
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From: TOAK western branch
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From: 40 miles Northeast of Indy..
last ones I got from the dealer was $.50cent per...
then I found these,, and they store is a 1/2 mile from the house..
about $4.00 per 100 with tax... I keep 50 and gave the Son the other 50...
https://www.fastenal.com/web/products/details/1166807
then I found these,, and they store is a 1/2 mile from the house..
about $4.00 per 100 with tax... I keep 50 and gave the Son the other 50...
https://www.fastenal.com/web/products/details/1166807