[Shotimes] Throttle body gasket

[George Fourchy]

On Sun, 9 Apr 2006 12:14:52 -0400, Mark Mucher wrote:

>Where does it go?  What are the possible areas of restriction?  I tried to
>RTFM, but I can't find anything - perhaps it's in the emissions FM?

I have a short block in the storage shed, across town, with the heads and fuel rails
off.  I seem to remember that the hose just goes to a 90 degree el that goes into
the block and vents the upper crankcase.  Using a flashlight on BD, I can see the el
just a bit farther to the center of the block than directly underneath the schrader
valve on the fuel rail.  The other small hose that goes to the front head is
probably the inlet, and the big hose is the outlet.  Somewhere, though, there needs
to be a valve to control airflow. otherwise the whole thing would look like a huge
vacuum leak to the intake.  Back in the old days, the PCV valve pushed into a valve
cover, and the hose from the other end of that went to a fitting on the carburetor
throttle body or intake base just below the carb.

>Maybe I should just vent the hose from the front cam cover to the open
>(ducking flak from tree huggers) for a while to see if that helps.  But it
>just goes into the intake behind the throttle body and ports into the TB
>where, again, I could find little or no restriction.  I CAN blow from the
>cam cover end of that hose thru the TB, but not without a little
>restriction.

You can take that hose off the head or throttle body, either one, then start the
engine.  Theoretically there should be a bit of airflow into the head which you can
detect with your finger by blocking the hose.  If there is no flow, then the EGR
valve, if there is one, is plugged, and there is your pressure problem. 

>Finally, there is a small hose near the IAB the goes to a solenoid and then
>to the canister (I think).  That is blocked (with the motor and ignition
>off), but that's probably normal.

This is the gas tank vent, that sends fumes from the tank to the carbon canister
under the right fender, and then when the computer senses the need, it opens that
solenoid and lets the fumes go to the intake.

Hope this helps a bit.

George