I am working on putting some custom gauges on my bike, but need to get adapters for the oil pressure sending unit and the water temperature sending unit that come with the gauges to work for the Magna (Dakota Digital, the company that makes the gauges, says they have adapters for metric bikes).
Here's the problem. I have no idea what size the Magna's water temp sending unit (I assume this means the one on the thermostat and not the one in the radiator, but I might be wrong) and oil pressure sending unit are.
Does anyone have this information? After talking with the guy at Dakota Digital, it sounds like I need the thread size and the diameter of each unit's "threaded" section. I have looked in the PDF service manual and cannot find this information.
My engine and its parts are off in another city right now and it will be a couple of weeks before I will be able to go there, so there is no way for me to check this myself. Also, I'm not sure I have the right equipment to do this. In addition, I am in South Korea and the Honda Service Center here is useless.
If no one actually knows this information, I would really appreciate anyone with a good Honda service guy, who can call him and find out this information for me. I'm really frustrated that I can't find this myself, but I'm hoping that one of you out there can help me out. To be safe, I think I should get the measurements for the oil pressure sending unit, the thermostat switch, and maybe the switch on the radiator, though I think that switch is only for the fan, if I'm not mistaken.
Any help is greatly appreciated.
Hi, Chokse,
I feel your pain there. I will look into the thread sizes later today. I have my latest '96 up on the lift changing the rubber, front brake line, etc., and can remove the oil and water sensors to have a look at the threads. I can measure the outside diameter, and the number of threads per cm. I don't really know how metric threads are specified, or what numbers you will need to order from the source you have located.
My manual for 3rd gens, on page 18-2, shows a "fan motor switch" going into the left rear of the radiator, so it appears your assumption in this regard is correct.
Hang in there, we will figure it out somehow.
I had a fan motor die on me a couple of years ago was pretty sure I remembered the wiring from the fan going into that switch on the radiator.
Hopefully we can get this all figured out. The info might also be helpful for any other members looking to get Dakota Digital gauges.
I did not get to the water temperature "sender" switch, but the one for the oil is 10.1 mm across the outside of the threads. There are 8 threads in 9.8 mm.
I just replaced the brake line with a SS one, so I measured the banjo bolts. They are the same diameter and thread.
The fan switch in the radiator left side looks exactly like the oil pressure switch on the outside. I did not remove it to measure it.
My suspicion is that they have one basic hollow bolt, since hollow bolts are expensive to manufacture. They drill a hole in the cap and mount various sensors, and drill holes through the shoulder to use as banjo bolts.
Hope this helps. Let me know.
Maybe we are looking at different oil pressure switches, but I finally got to mine and it is definitely NOT the same size as the brake banjo bolt. It has a much larger diameter (almost double) than the banjo bolt, and the threads are definitely wider on the oil switch than on the banjo bolt.
It looks like the oil pressure switch uses a 1/8" pipe thread on it.
Now I need to dig up the thermostat switch and find out what size it is.
May I suggest you take it off, go down to the hardware store , match it to one of their nuts and then check the package for the actual specs.
Had you read my original post, you would have seen that I am not in the United States and that the oil pressure switch and temp sending unit were in another city, and I would not be able to get to them for a few weeks.
Even if I had them in my possession when I posted, I am in South Korea where we do not have places like Lowes, Home Depot, and so on. If you want bolts here, you have to hunt down a small store, about the size of your average bathroom, that sells nothing but bolts. Were I even to find one of these stores (not easy in a city with 15 million people and no Yellow Pages or street addresses), they will only carry metric bolt sizes. From all I have read, the oil switch on the Magna is SAE size (perhaps 1/8"). Finally, even if all the stars and planets aligned and I found a local bolt store with both SAE and metric bolts, it is 100 percent certain that the guy working there will actually know nothing about bolts (he's just there to put the amount you want into a bag and to tell you how much it will cost). There is also no packaging, as all the bolts and nuts are in plastic bins with a simple size given (like M8, M12, etc.).
I came here because I do not have a way to verify the size of these items where I live. I tried to make that very clear in the original post.