GeminiFire

Hey,
so among having a truck with a newly rebuilt motor that wont run(thats on my other thread also in this section), I thought instead of murk up that thread with off topics i would just have another thread dealing with what seems to be a small problem.

Anyway..

I dont know how a temperature sending unit/gauge works but i aim to find out and fix mine. my 1980 4x4 long bed recently got an upgrade from a stock 20r with a weber 32/36 and headers to a 22r with an rv cam, big pistons header and the same weber.. great for 2 months.. except even RIGHT before the swap the temp gauge worked great on the 20r. i sold that motor immediately before i could rob the temp sending unit because i come to find out that the 22r isnt sending a signal.. or my gauge randomly died(which i think is unlikely) so i just went out and bought a NEW sending unit and took the gauge cluster out to match up the correct wire from the back of the cluster to the sending unit.. still nothing!!

Im wondering what components make up this system and if there are any ways to checking/fixing this?

is it a 12v system or what? if its resisters and stuff i dont understand that, but i can follow instructions!

anyway thats why my motor just overheated and im trying to get it running again.. lol i figured i better get this fixed this time.

Is there something i could check with an ohm reader that would help out?

Thanks for any help!

oh and because i know you guys will ask, the guage reads like the truck is off.. all the way off the map to the left(towards the cooler side)

GeminiFire

BUMP! im about to get another motor and i really need an answer to this so i dont have to replace a motor in this damn thing for a LONG time lol.. thanks!

GeminiFire

damn ive searched for this answer and ive found other threads with the same or very similar questions with no answers. this is my second time posting this question with no answers. whats up guys? stumped? lol hit me up i really dont want to overheat again!

mightymouse

iTrader: (6)

went through similar problems here's my old thread. hope it helps but i learned to live with it to an extent. https://www.yotatech.com/forums/f120...issues-184271/
best bet is to get a infrared temp gun or borrow one. look into an after market temp gauge as well.

creswellhick

my didnt work either def just go with a aftermarket there more accurate any way

GeminiFire

i guess im looking for a more specifics about the stock gauge. its frusterating to me that first of all i dont understand how it works, and second, why its worked perfectly for years and now all the sudden after the 20r to 22r swap it wont work at all. i know its just something simple but i was hoping to pick the brains of someone who knows specifically what could be going on. thanks for the thread link i had actually found that before.

scottd

Sounds to me like your problem is most likely wiring related (are you sure you have the wires hooked up correctly?). Agree that it is unlikely that the gauge quit while you had the motor out and two non-functioning sending units is also unlikely. I think you should at least get some kind of a reading on the gauge even with a malfunctioning sending unit.

Some excerpts from the '80 FSM that may be helpful:





x3 on the aftermarket gauge. Easy to install and gives a clearer picture of what is happening temp wise. Also helpful as a check to see if the stock gauge is reading correctly. I have an aftermarket temp gauge in the lower gauge pod where the ammeter used to be in addition to the stock temp gauge.

GeminiFire

thanks for the info. i think because my amp meter has never worked in the lower gauge pod of the truck, ill just spend the 25 bucks to get an aftermarket gauge and put it there. although i like the idea of it being stock, i have to face the fact that it cant always be that way with these trucks. sometimes i feel like these trucks were totally well designed and sometimes i remember that im wrong, and that no matter what i do, this truck will ALWAYS have an attitude. oh well i love him anyway.

scheefdog

Mine wasn't working when I first bought my truck(79) and it ended up being a loose wire on the back of the gauge cluster. Check where all the wires go into the round plugs on the back of the gauge cluster. One of mine had come part way out and ended up fixing the temp gauge.

GeminiFire

hmm.. it seems i need to take my gauge out and see if thats the problem. thanks ill try that!