temperature SENSOR wiring question

[bob johnson]

I was trying to check my temp sensors to see if they are working according to the factory manual.

one sensor has two wires and the other has only one wire.

the dual wire unit has a tan with blue wire, and a white with black wire...the other (starboard) has just the Tan with blue

in the book they also list a yellow with( cant remember the stripe color now) my motor didnt have that color.

each color has its own test specs!!!!!

the tan with blue is supposed to close at 240 + or- 6 degrees.. and then close on the down fall at 215 degrees..

the whire with black is supposed to close circuit at 105 degrees and open back up when the temps falls to 90 degrees!!!!!!!

my question is what is the white wires purpose??? that is really low temperature....what is being signaled when those temps are reached???

is the timing changed because they say the motor has 'warmed up"???



by the way, its a tricky setup testing those units in heated oil. trying to make contacts with the right pin... using a cheapo kitchem thermometer( I used an infared thermometer as back up)

dont heat the oil too fast...because the temps are changing faster than you can keep track!!


bob

 

[Chris1956]

Re: temperature SENSOR wiring question

Bob, You might tell us the year and HP. The tan/blue wires are overheat sensors. They should short at 200*F or so, open at low temps. The other wire is for Quickstart, I would think. It will short when cold and open when the motor is hot. The tan/blue wires should also be hooked to the SLOW system (if your motor has it), via a blocking diode.

 

[bob johnson]

Re: temperature SENSOR wiring question

here and i thought I was giving too much info!! ha ha

for sure the year would help

1995 115 ocean runner

probably has the quick start, and SLOW system...

one of my heads was running up 200 degrees once in a while... and i was going through a long drawn out trouble shooting process...

I eventually bought two useds heads made sure they were clean and clear and installed a new seal for the t-stat and installed them... i was left with two of each sensors( since the used head came with the sensors)

I figured i check them all..

I ran my motor on muffs yesterday with NO sensors....

no alarms!!!

motor ran ok....seemed a little harder to start than normal...

and it died after 2 minutes or so...but once I got it running again...ran for 15 minutes before i shut it off..


temps were higher than i had hoped for ....seemed to get to 160 faster than normal...and just sat there..

I wont change anything unitl I run it WOT...

bob