so my cousin helped me pull my heads to have them ported and polished. well he took the heads in for me and didnt remove the bracket on the back of one of them and also a sensor that was in the side of one of them. when i got the heads back the bracket came with them in a box but the sensor (thats the parts that i dont know what it is) was no where to be found. all i know is it was on the passanger side, was brass looking, and would have required a large wrench to remove. anyone know what it was? the car is an 85 IROC with a 305. also are there any other sensors that screw into the heads? thanks.

 

The sensor on the side might be the temperature sender. And you can get those at a parts store.

 

If your sure it was on the passenger side, than it's the coolant fan switch. With the cylinder head on the car, the fan switch would be towards the rear, in between the #6 and #8 spark plugs. You can get a new one at an auto parts store. It should look like this:


The only other sensor/switch in the cylinder heads is on the driver's side cylinder head. The coolant temp. sending unit (what the gauge in the dash uses to show coolant temp) is located towards the front of the driver's side cylinder head, right in between the #1 and #3 spark plugs.

 

it didnt look like what you posted a pic of. when i was at autozone earlier i looked at one of their posters on the wall and it looked like what the had labeled as the knock sensor.

im pretty sure it was on the passanger side. on the other head the same place just has a plug.

 

The knock sensor should be on the engine block itself, not the cylinder head. It is on the passenger side of the block, but it's right above where the oil pan bolts to the block.


EDIT: Wait, does your 85 have a mechanical or electric fan? From the info I have, an '85 305 has a mechanical fan, which means it wouldn't have a fan switch in the cylinder head like the electric fan cars do. So, whatever part it was, it's not a fan switch like I thought, if you have a mechanical fan.

 

i have an electrical fan. but i have it hooked up to so i can turn it on or off with a switch in the car. i think you are right about what it is because you descibed where it was located. would i just be able to use a plug there?

 

You sure can if you want to. I'm pretty sure those threads are NPT (national pipe thread), so a quick trip to the hardware store should yield what your looking for.

 

cool, i figured that and already picked up some from autozone. thanks