Ok I am getting ready to install the oil temp gauge to replace the stock ambient air temp gauge on my new Street Glide. I am not going with the HD method of install, and instead going to do it like most here, by using the secondary oil drain plug for a access point for the sending unit. I need to know what size adapter to use. Can someone please tell me the size so I will know what to look for at the local Home Depot.....the home depot has a very well stocked NPT fitting selection, and I am 995 sure they will have it.
I had a few NPT adapters laying around in my shop from previous gauge installation jobs, and I have one with the same thread size and pitch as the stock drain plug. Does anyone here know if both the drain plugs on the oil pan of the newer touring models both have the same size/pitch thread? If that is the case then I dont need to go out and look for a adapter, I can use the one I have. I would like to be sure though.
My other question is if I should use any thread sealer on the fitting or sending unit like Teflon tape, or they have a Teflon tape now that is specifically made for environments where oil will be present....its sort of a yellowish color. So did anyone have to use anything like this to get a good seal?
Last question is has anyone who did the install the HD way, and then changed to the secondary drain plug method for one reason or another, notice any real difference in how the gauge read.....was it more accurate one way or another, or did you notice any real difference to speak of one way or the other???

I like to do jobs right the first time, and I like to have everything needed to complete the job on hand when I start........so I want to thank everyone here who helps out not just me with these jobs, but anyone who helps out another forum member with whatever job they are taking on!!!

 

I don't recall having to use an adapter to install my sensor. It screwed right in. Yes, it's the same as the drain bolt.

Yes, teflon tape.

No, never installed the HD way, can't comment on that.

 

do not use teflon tape. you need a ground at the sensor. tape interfers with the grounding. If installed properly, there will not be any leaks.

 

The bushing I used to install the sending unit in the oil pan was 3/8" male NPT X 1/4" female NPT on my '04 EG 88" motor. I know that the oil drain plug was smaller diameter than the casting plug/allen head flush mount plug that I removed to install the bushing. Every other installation like this has used the bushing I used. Soos has posted previously providing a NAPA part number, but it is the same bushing.

I also used an O ring, similar to that used on the oil drain plug. I didn't use teflon tape.

Don't know about temp differences between this sender location and any other.

 

I know for sure that on the SG's the allen head plug in the oil pan does not use the same thread size as the sending unit/sensor, so a adapter must be used. The sensor then threads into the adapter and then the adapter, with the sensor in it is installed in the drain pan.

 

Thanks I will be going to the Home depot in a hour or so to look for it.....
So you used a 0-ring on the adapter....like the o-ring on the HD drain plug, and had no problems with any oil seeping out?

 

I took my sending unit to the NAPA dealer to make sure I got the right part. I'm pretty sure I told him I needed the 3/8" plug. I assembled the sending unit to the plug then pulled the plug outa my oil pan and inserted the new plug. To small, it wouldn't thread. I lost all my oil because I had to take the original plug back to the NAPA dealer to get the right size.
Another tip: don't tell the NAPA dealer it's for your scooter. He will loose all enthusiasim for helping ya and tell ya you have to go to a Harley Dealer for the part.

 

If this is in an 08:
a. Most guys were successfule at NAPA. I have been to the Home Depot adapter area also. No joy.
Bring the Plug with you and the Sender with you. NAPA is the place.
b. No teflon tape. I used Loctite white.
c. Sender in the pan is more accurate of the overall oil temp.
I have pics in image-shack but it's not playing well right now. When it does I will post them (im gonna move em all to phot-bucket I think)
Someone else has some really good pics however that I saved. Maybe they will come along.

That aint no joke.





Dont forget to change the color of the light bulb to match:




Take your tank off, easy. The fuel connection is a quick release and there is no cross-over on the 08 model tank.

 

Biz: I used the O ring between the oil pan and the bushing; didn't use O ring for the sending unit. I've had it installed for about 8K miles with no seepage at all.

Funny timing on your post because last Friday the Service Manager at my HD store wanted to see my installation. Seems they hated the HD instructions and had been drilling and tapping the oil pan to mount the sending unit and he'd had heard from one of the service writers of the alternative installation location. He looked at my installation (which is the same one used by many HDFers before me) and wrote down the bushing information I provided above--that's how they will do it from now on.

Regarding the O ring, it is not mentioned in the posts by others using this installation location; I did it because that's how the other drain holes are done on the bike and figured it wouldn't hurt--so far it hasn't.

 

Try this thread with pics

https://www.hdforums.com/fb.asp?m=2403796