a resistor is placed in line for the coolant temp gauge
so it will read correctly w/ the gte sending unit - the
value that phil spec'd was 330 ohm - anyone else
using a different value? my gauge is below 'c' - no
resistor above 'h' so wiring is good & new sending
unit. i can play w/resistors to make the gauge in the
middle, but im sorting out other problems & need
the gauge to BE correct . not MADE TO BE correct.
thanx john

 

Use the 'Binary' experimental method as I did. If a 330 resistor goes off the scale one way, and no resistor off the scale the other, start with half that value, about 150 or so, then you'll know which direction to try. When I was experimenting, I just made up a rudimentary plugin mechanism, so I could just temporarily plug in the resistor to see what I got. Naturally, give the engine plenty of time to warm up to normal temps before making your judgement.

P

 

I ended up using the 330ohm resistor and the temp reading seems to be right on. I'm using a fluidyne so it runs pretty cool as it is.

 

Hiey Chris, How 'bout some pics of your installation? phil@fly-hawaii.com

Thanks!

 

hey phil - i was't sure if you were around (vacation) -
dropped you a e-mail a week or so ago.
if chris is using a 330 w/ "good" readings, then its
me - my scanner is reading 194 degrees but you
cant always trust their readings either. the t-stat's
probably hung open.
thank you both - now i know to move on w/in the
coolant system (gives me a reason to buy a new
i.r. gun for temp )
john

 

Glad I could be of assistance John

By the way Phil, I'll send you some pics this weekend.

Chris

 

I tend to use potentiometers a lot. Variable resistors.

If phil says 330, it sounds like he's da man. But if you doubt it in any way and want to play with it and tweak it, try a potentiometer. you can vary the resistance accurately in 1 ohm increments from 0 to 500 ohms and really get a feel for the perfect setting for your needs in any aplication.

 

i considered doing a little pot diddling on the gauge
but i'm going through the growing pain stage
& wasnt sure what my true water temp is. computer
scanners can lie about actual readings (been
there hundreds of times over the years)
& i really didnt want to adjust the gauge to read
normal when it was truely cold.
when i finish playing w/ my -12/-10 fuel lines &
get back to the temp issue i'll post what value i used.
(in case someone finds this in a search)
i'm sure it will be the 330.
thanx john

 

anyone have a pic of this done?

 

I believe this is what you seek - searched tach & temp mod:

https://www.clublexus.com/forums/per...-tach-fix.html

In essence you jump the 2 connectors that plug into the cluster for the tach
(1st pic)

Short or bridge the resistor on the back of the cluster for the temp gauge.

There is another thread on this also, just can't find it.

 

yeah i found that same thread. but the pictures are horrible. i have no idea what that is. its like the guy smudged peanut butter on his less than VGA resolution camera phone, then wiped it off with sandpaper to take a picture.

 

https://www.clublexus.com/forums/per...with-pics.html

 

did that. no workie. thats why i think i have to recheck my grounds. my check engine light used to come on. now it doesn't. i still need to recheck my harness extending. make sure soemthing didn't go wrong.