B18 motor

just replaced the thermostat....fuses are good....if I jump the cooling fan switch connector with a piece of wire the fan will kick on.

guessing its a bad cooling fan switch?


thanks

Mike

 

sounds like you have a good diagnosis there with the sensor!

 

Try bleeding your coolant from air that may in the coolant system.

 

replaced the cooling fan switch ...fan still not kicking on...what else should I check?????????????

 

coolant has been replaced, new water pump, new thermostat and new cooling fan switch only thing left that I know of is the coolant temperature switch....

 

is it reaching a temperature where the fan should even be kicking on? as in, its overheating? hows the car acting? is the headgasket blown? or is the radiator or cap leaking?

if you can jump the 2 pins of the fan switch together and the fan kicks on, then you can immediately be 100% sure that everything in the system is functioning properly besides the fan switch, as long as its being heated up to proper temp. you can always put the fan switch in a small metal cup of coolant (the bottom half of a soda can works well), heat that up with a small torch, monitor the temp with a probe that'll read up to 250 deg f., and monitor continuity on the pins. a good switch should close around 190-210ish. a bad switch won't close to beyond 230. it really doesn't take much to rig up a good fan switch tester.

your only other possible problem is that the coolant (or air) thats contacting the fan switch isn't reaching fan switch operating temperature.

 

 

temp gauge goes about half way so I think the fan should be kicking on. The car was only overheating before if I sat in traffic at a dead stop. Cap or radiator arent leaking. can it be a relay or the coolant temperature switch?

 

There is a 1 wire sensor underneith your distributor, make sure that wire didnt break, if it didnt replace that sensor its the temp sensor

 

im guessing that works the cooling fan switch right?

 

check the single wire, and check the radiator fan relay that it eventually leads to. it's probably the relay. the relay is the only thing you haven't changed in the circuit i believe. and if you're jumping the switch and it's kicking on the fan, then that is the only thing that is going on. the switch is working, but it isn't receiving any juice from the relay.

 

everything works guys...just took it on a longer ride and the fan turned on. I'm happy now haha


I think it was the cooling fan switch that was causing the issue before....its not the one you have pictured above the one I replaced was on the thermostat housing

 

hey so wat was the problem? why did it over heat?

 

sorry i dont mean to be a dick, but are you serious.......? did you not read anything?

 

Well iam only in da 3rd grade i dont realy understand it

 

yeah, i figured the old fan switch was bad, you replaced it, and it just hadn't heated up hot enough for your fan to need to kick on yet. by the way, that little 1-wire sensor on the head under the dizzy works the coolant temp gauge

 

Not to hi-jack the thread but I have the same problem. Checked the fan and it works. I guess I have a 50-50 chance from here.

Would you change the fan switch first or the engine temp switch.

Sorry if I offended anyone.

 

i actualy replace the coolant temp switch or was it the fan switch not sure....its on the same housing where the thermostat is....on my b18

 

I had a similar problem and it turned out to be a bad wire, had to replace it and no more overheating from the fan turning on when it wanted to.

 

Thanx for the replies. I replaced everything, rad, switches, thermostat, cap. It works fine now.

That was easier than trying to figure it all out.

Thanx Again