Koso slim water temp gauge install (1 Viewer)

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Could those of you who have done this with a fuse splice give me some info on the brand of fuse splice you used and where you got it. I went to install my gauge tonight and used an add a fuse from O'Reillys. I plugged it into the 10 amp dash fuse and followed the instructions but I could not get the instrument cluster to work with the add a fuse. Does the gauge have to be plugged into the add a fuse and connected to ground to allow the add a fuse to work properly. I didn't hook the gauge up to it. I just plugged the 10 amp fuse I removed from the fuse block into the add a fuse and plugged it back into the fuse block in every direction possible and it would never allow the instrument cluster to work. I hooked the gauge up to a 9V battery and it worked awesome so I just got to figure out how to power the gauge permanently.
 
I never hooked the gauge up to the fuse tap thing. I put the 10 amp fuse for the instrument cluster I pulled from the fuse block into the add a fuse but no matter how I plugged the add a fuse in the instrument cluster slot the cluster would not work. Does the koso gauge have to be plugged into the fuse tap to allow the instrument cluster to work. The fuse tap will not allow the instrument cluster to work right now but I have not wired the koso into the tap
 
the Koso gauge needs to be grounded by the black wire
 
My problem is not with the koso gauge it works fine when I give it power and ground with a battery. When i put the fuse tap into the slot labeled dash the koso won't work and my instrument cluster/dash won't work. I think I got a faulty fuse tap
 
what's the rating on the add-a-fuse fuse ? - should be plugged into the same rating in the OEM fuse block

have you tried it in the radio fuse slot ?
 
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10 amp yes I tried it in the radio slot and same thing, it prevents the radio from working like I pulled the fuse out of the slot. I am 90 percent sure i got a faulty fuse tap. I am going to pick one up tomorrow from a different store
 
FYI. For anyone reading through this thread and looking to do this mod, Glowshift seems to no longer carry the 40mm kit. Either 38mm, 39mm, or 42mm. Im looking into updating and doing alot of cooling pm, so this is definitely going on the list. Thanks for all the info yall!
 
FYI. For anyone reading through this thread and looking to do this mod, Glowshift seems to no longer carry the 40mm kit. Either 38mm, 39mm, or 42mm. Im looking into updating and doing alot of cooling pm, so this is definitely going on the list. Thanks for all the info yall!

No need to get an adapter. Just go grab a tap and a t handle like the one I showed. It will give you a really clean install right into the water pipe.
 
Could someone post a picture of where they have the ground wire routed to? My gauge stopped working and I noticed the group wire just hanging there. I can't tell where the previous owner had it routed to and there is literally one strand of wire sticking out of it. Did you solder it on?

Thanks
 
The wires are tiny. I just took a 22g ring terminal and overlapped the wire a couple times to crimp it on. Grounded it to this bolt. Lots of other bolts to ground it to down there. image.jpg Works fine.
 
So you went with 38mm, I see from the link they don't sell the 40mm. Also is see the display does not come in green.
Does yours change from blue to red?
So, this are the only two parts I need?
THANKS!!!! For the links
The Koso gauge I have only has blue light output.
That should be all you need to complete the project.
 
It is like Toyota left a flat spot for the Koso Temp Sensor! Nice and flat and facing upright.

Took longer to remove the distributor than to tap and drill hole for sensor.
Drill and 1/8 NPT were correct size.
A little PTFE (Teflon Tape) and your good to go.
Do not tap that hole too deep, just break thru with threads.
NPT (National Pipe Thread) are fully tapered (Think Cone) unlike a regular tap which is tapered only on the tip (Think Pencil).

Those complaining that the LCD grabs your attention, must not know its purpose.
My only question is at what Temp is Maximum safe?
I want to print a "Max Temp ???" Label for other drivers, but I have to know what that temp is, I'm guessing it's over 212 since system is under pressure.
If your not interested in plopping down $100 for Scan Gauge, this is your insurance plan.
I'm lazy or I would add this to the "Under $100 Mod Thread".
 
I love the slim gauge so much in my 80 that I threw one in my cobra!
Next is my 4Runner.

image.jpeg
 
Since I just purchased my first 1FZ-FE and have been staying up at night obsessing about water temps (even though I haven't even picked up the 93 yet!). I just ordered the Koso temp gauge and the inline piece so I can install this in LA when I fly out to pick it up. It will give me something to look at on the 1800 mile trip home.

Thanks @half k cruiser
 
I have a question before installing my Koso thermometer kit: how much coolant will drain out when I cut into the upper radiator hose? Need to make sure my bucket is big enough.

Once installed, I'm looking forward to receiving real time, specific temp readings from the coolant as it does its job!

For those looking to add this mod, I found a Koso super slim thermometer (fahrenheit) and a separate 40mm adapter both on ebay. The thermometer came with the sensor, gauge, and cord with plenty of length, it's model # BAO24B11, made in Taiwan. The temp sensor threads fit just right with my adapter's 1/8 NPT threads.
 

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