macinrock

For a 1992 Firebird formula 305: Which sensor allows the fan to come on at the proper time? It works with the air conditioning controls but doesn't come on by itself. I've already replaced the coolant switch between 6 & 8 cylinders on the head. Is it the switch beside the water neck? Trying to stay cool.

j dezzy

iTrader: (12)

do you have dual fans or single?

macinrock

It is just a single fan system. It is possible I didn't let the engine get hot enough. I have seen several different temps for the switch to activate...228degree, 232 degrees. Do you know how hot it needs to be? thanks

j dezzy

iTrader: (12)

you might have a bad relay. But I'm not sure since it wtill works with your AC. My car doesn't even break 200*. How hot does your car normally get?

macinrock

I have been running with the fan on from the a/c control so its hard to say what temperature the car normally runs at. i actually just put a 160 DEGRREE thermostat in. I have been running without one for almost a year. These past 2 days it seems to stay around 160 but my daily commute is only about 8 miles so i don't have much of a chance for it to get hot.

j dezzy

iTrader: (12)

8 miles is more than enough for the car to get to a good temp. try leaving the fan off and see if the car over heats and the fan kicks on on its own. I've got a 180 thrmostat and she doesn't break 200* and I usually don't have to use the fan unless it's a pretty hot day or I'm doing a lot of stop and go driving. I don't have a temp sensor for my fan, it's controled by a switch, for now.

VenomX-87

i want to ask you j dezzy Do you have the funcional grills on the front of youre 84 T.A or are they the solid inserts like my car has?
Because the temp you say you get is like my car is with the inserts out, When they are in it gets like 40/50'F hotter. (with old fans, Have not tested new ones yet)
EDIT: i think the old fans were actualy restricting the airflow through my rad, They only flowed around 1,700CFM shrouded so it may have just been that.

j dezzy

iTrader: (12)

Yeah, I've got the open grills on my car. and my hood is functional too. I think that helps a little too since It's open and not enclosed over the carb. I've also got a 4 core radiator.

VenomX-87

What kind of hood have you got?

To Macinrock the normal "FAN ON" temp is around 238'F, That is way to high for me tho.
to test the system pull the wire off the head and ground it with ignition on, If the fan comes on the system is ok.
To fix this you can put a lower temp switch in the head or hook the wire going to that Temp switch to a manual switch that grounds the connection for manual activation of the fan.

j dezzy

iTrader: (12)

The original functional turbo buldge hood. When I got the car it didn't have the flapper in it that opened and closed the vent with the vaccuum of the car. it just had a block plate. I've since took the block plate out and modified a flapper with a door lock actuator so that I can open the vent when I want and it will fit on my car with my holley carb and x-stream air filter. I'd have pictures up of the thing...but a friend borrowed my camera and lost the USB cable...My vbgarage has some pictures of the car if you want to see the hood.

macinrock

I will give that a try. I have a regular style hood. I am going to try to post some pix soon

l_dis_travlr

For single fan systems, (at least my 90 305 TBI Formula), the
temp control switch is located by the starter, and the knock
sensor, in the block. PITA to get to...

macinrock

Well none of it really matters now my tranny just bit the dust. No more 3 and 4 gear. looks like i am in the market for a 700r4. thinkin i would like to buy a new one...anyone got suggestions of someone i can get a tranny shipped to hawaii??

j dezzy

iTrader: (12)

wow...Your best bet is to buy one brand new from a place like summit...that'd be the cheapest way to go on shipping...if you bought a used one off the board or such the shipping will kill you, and most people won't go for it.

summit part # TCI-371000