I was wondering how to remove the air cleaner sensor? I was unsure how to, I sand blasted around it the best I could. After blasting there is no damage and I cleared it out with parts cleaner. Is the senor OK? What does this sensor do? Does it display anything on my gauge cluster? My car runs fine without it.
Also where can I find a new crankcase filter? Can I make one?

 

The sensor is part of your thermostatic air cleaner system which operates the heat riser on the right side of your exhaust called and air temperature sensor. It does not have anything to do with your gauges but it does recirculate exhaust gases into your carb to quicken the warm-up process and reduce emissions, as always.

I don't think sand blasting would hurt that sensor. You should be fine, and if you don't notice a change in your idle, I wouldn't even worry about reattaching it, because it wont make you fail smog either.

Cheers, Tony.

Oh, and yes, you can just make a new pcv filter or you can buy the one on this page:
http://corvetteamerica.com/cf/displa...rd%3A%20filter

 

how do you remove the sensor? I don't want to break the bugger?

 

should unscrew out

 

The A/C switch you’re referring to opens the two air doors on the fresh air intake of the air cleaner. When the air temp inside the air cleaner reaches its set point it allows vacuum to flow to the air door actuators. Removing the switch will not allow the air door actuators to function. There is a metal spring clip on the bottom where the vacuum lines plug into that needs to be removed to remove the switch.
You can remove the switch but you will have to plumb the actuators to full vacuum so the will remain open when the car is running.

 

Brian is Dead On and you can purchase a new breather filter from any Auto Parts Store.

 

I'm afraid I must disagree, unless of course I am mistaken. The temperature of the air has nothing to do with the opening and closing of those valves, they are solely controlled by water temperature and a thermostatic vacuum valve operates them. But I could be very wrong.

 

Actually, as Brian mentioned, the flaps in the snorkel air cleaner are controlled by vacuum. During initial cold startup, the flaps close allowing heat from the exhaust manifold to assist with warming up the motor as opposed to just cold air. Eventually, as the motor warms up the flaps open up to bring in cold air and close a door to the exhaust heat. I don't see how water temperature controls this process...

 

On a 1978 corvette there is a thermostatic SWITCH that is implanted onto the water neck with 2 or 3 vac. lines attached to it, when the engine is cold the switch is closed impeding vacuum from opening the flaps and forcing the engine to breathe from the heat stove, when the engine reaches operating temp. the switch opens allowing vacuum to open the flaps and allow cool air to flow into the carb.

Like many things on a corvette, it is OPERATED by vacuum, not CONTROLLED. Vacuum is the method used to open and close the valve, but it is controlled entirely by the temperature of the engine, or "water temperature". This is the basic principle of the warm-up system, an engine performs most efficiently at operating temperature which is measured by water temperature, the temperature of the air does not change drastically from the moment you start the car to the moment you turn it off, especially if you have cowl induction.

 

...the air cleaner mounted temperature sensor/vacuum controller that koni9 originally asked about is the only controller for the Thermostatic Air Cleaner (TAC) damper flaps in the air cleaner inlets. When air at the sensor is cold, it allows vacuum to close the damper flaps. Intake air is then drawn through the heat stove on the driver's side exhaust manifold and warmed, and then drawn into the air cleaner.

As the exhaust manifold warms, the temperature sensor/vacuum controller reduces vacuum to the damper flaps to reduce the amount of manifold heated air entering the air cleaner and thus maintain a more or less constant air temperature entering the carb.

If the outside air (not flowing across the exhaust manifold) entering the air cleaner inlet is warm enough, the temperature sensor/vacuum controller in question cuts off vacuum to the spring loaded damper flaps and they close fully so no manifold heated air enters the air cleaner inlet.

The thermostatic switch on the water neck (coolant thermostat housing) controls the Early Fuel Evaporation (EFE) system only. When everything's cold, the switch allows vacuum to close the heat riser valve below the passenger side exhaust manifold and pass exhaust under the intake manifold. When engine coolant at the water neck warms sufficiently, the thermostatic switch closes, vacuum to the heat riser controller valve is cut off, the heat riser valve opens, and exhaust gas is no longer diverted under the intake manifold.

Since my Vette is strictly a fair weather machine, I've disconnected both of these systems and removed the heat stove and heat riser valve actuator. The motor seems more responsive and does idle better when it's fully warmed up.

Later...
Jerry
78IndyPace

 

And now, for one more person's $.02 worth. On my '81, the vacuum switch for the cold air doors is controlled by water temp as described above, however, the doors are CLOSED by vacuum (not opened), so you can disconnect everything and all will be fine. God bless, Sensei

 

Thats the way my old system worked.

 

On my 80, vacuum from the intake is allowed to pass through the cold switch which closes the flapper. When it warms up the switch closes and cuts off the vacuum to the flapper allowing it to open.