Oil Drain Plug size

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craig60pan
Posts: 180
Joined: Fri Dec 31, 2004 2:37 pm
Bikes: 1960 FL
1951 FL
Location: Atlanta

Oil Drain Plug size

#1

Post by craig60pan » Wed Nov 25, 2009 7:58 pm

Went to drain the tranny oil on the 51 and found yet another creative solution? Or maybe not.
The plug on the left is the drain plug that came out of the 51 and on the right out of the 60 FL
One parts book I have (61 parts catalog shows 701A for all years from 48-61. In the 57 parts book it shows 37-57 part 700.
My questions are; do these look like the 700/701 plugs?
Did the 701 supersede the 700, which required a bigger hole to be drilled to accommodate the larger plug?
If so does anyone know what size whole? What size tap?. While the aluminum is pretty soft as metals go I assume the drain plug is not a self tapping one but I could be wrong.
Any help would be appreciated. The treads in the tranny are almost gone so it's either go bigger or helicoil
CJ
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panz4ever
Posts: 513
Joined: Fri Aug 12, 2005 5:45 pm

Re: Oil Drain Plug size

#2

Post by panz4ever » Thu Nov 26, 2009 5:36 pm

My 41-54 parts book shows lists the part number as #700. Looking at the V-twin book and it list the #700 as being 3/8 x 24 thread (BT case plug). Above it list #707 as being 1/2 x 13 thread (74 Trans). Probably does not help much. But hopefully someone can clear it up. At least you have a starting point.

My drain hole is the size of a mack truck. So the answer to your question will also allow me to put a correct fix to mine. Tranny is coming completely apart so filling hole and drilling/tapping correct size hole will be no problem.

craig60pan
Posts: 180
Joined: Fri Dec 31, 2004 2:37 pm
Bikes: 1960 FL
1951 FL
Location: Atlanta

Re: Oil Drain Plug size

#3

Post by craig60pan » Thu Nov 26, 2009 7:53 pm

Panz
The little one is 3/8x24 and the big one is 1/2x13 so what I have in the 51 appears to be the stock plug.
The case does have enough meat on the threads to hold the plug but I think that the later plug, which also has a washer that the early plug does not, is a better long term solution.
If it needs to be original then at least through 57 the 700 without a washer seems to be the correct one.
If it needs to be leak free the 701 should be a better choice. When I drained the case, it had about an oz of oil in it but the bolt was tight.
Now it also sat for 30 years so ......
For now the 700 plus some Teflon pipe dope should keep it dry but when I rebuild it my initial inclination is to go with the 701.
CJ

craig60pan
Posts: 180
Joined: Fri Dec 31, 2004 2:37 pm
Bikes: 1960 FL
1951 FL
Location: Atlanta

Re: Oil Drain Plug size

#4

Post by craig60pan » Thu Nov 26, 2009 8:24 pm

From in the 2009 Colony Catalog

B. Quality reproduction of drain plug and brass gasket used on
Sportster transmission, motor case, oil tank and Big Twin 1937-1986
transmission. 1/2-13 Thread. OEM 707.
Stock No. 8494-1 Chrome Plated
Stock No. 8495-1 Cad Plated

C. Quality reproduction of original Harley motor case drain plug,
OEM 453-11/700, fits Big Twins 1911-1970. 3/8-24 thread.
Stock No. 8116-1 Chrome Plated
Stock No. 8117-1 Cad Plated
Stock No. 9675-1 Parkerized
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