Oil pan "Hex Plug"
Outstanding HDF Member
Joined: Dec 2012
Posts: 2,557
Likes: 235
From: Texas
That is where HD puts the sending unit for the oil temp indicator kit upgrade. One terminal oil temp senders typically used on automotive aftermarket gauges need to ground to the oil pan through the threads so using Teflon thread seal tape might not work. The HD sender has two terminals and is internally grounded. I "discovered" this when I installed a $30 automotive gauge and sender and It didn't work...Duh!. When I took off the tape, it worked but leaked without sealant. Since the gauge didn't match the HD gauges very well and was really messing with my OC, I replaced it with the $127 HD kit this time using pipe thread sealant. I am liking it so far...
That is where HD puts the sending unit for the oil temp indicator kit upgrade. One terminal oil temp senders typically used on automotive aftermarket gauges need to ground to the oil pan through the threads so using Teflon thread seal tape might not work. The HD sender has two terminals and is internally grounded. I "discovered" this when I installed a $30 automotive gauge and sender and It didn't work...Duh!. When I took off the tape, it worked but leaked without sealant. Since the gauge didn't match the HD gauges very well and was really messing with my OC, I replaced it with the $127 HD kit this time using pipe thread sealant. I am liking it so far...
Seasoned HDF Member
Joined: Apr 2008
Posts: 23,399
Likes: 8,509
From: Spartan Country, Michigan
Roguebear and Airborne... I was 13Bravo and I would have woke your *** up anytime during the night!!!
Gents.... thank you for your service. And welcome home!!!
Go Army!
Gents.... thank you for your service. And welcome home!!!
Go Army!
Outstanding HDF Member
Joined: Dec 2012
Posts: 2,557
Likes: 235
From: Texas
The MoCo kit comes with the adapter and does not sell it separate from the kit. It is a brass 3/8 NPT external-1/8 NPT internal thread adapter, easy to find at Lowe's or Home Depot. It is pipe threads so you will have to use thread seal or it will probably leak. MoCo calls for Loctite 565 Thread Sealant...I used a Permatex equivalent
Advanced
Joined: May 2010
Posts: 60
Likes: 3
From: Baltimore, MD
I know I'm resurrecting an old thread, but will I need to add any additional oil since I removed my "THOU SHALT NOT TOUCH THIS" plug by accident as well? Service manual calls for 4qts but do I do 4.5ish to refill the sump? 2010 RKC
Tourer
Joined: Sep 2009
Posts: 484
Likes: 38
From: DE
Check your dip stick oil level. Oil should of come out the hole since that is where the optional temp gage goes and needs to be in the oil. I used that hole to supply oil to my S&S motor per their instructions- so I know there is oil above that hole
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Joined: May 2010
Posts: 60
Likes: 3
From: Baltimore, MD
