Small block won't stay running


#1

I just bought a 1982 Chevy c10 305 small block.
It had an oil leak so i began putting new valve cover gaskets, and then New Valve Covers(Edelbrock).
Because the covers were taller, I had to remove the EGR valve and bend a new fuel line.
There was a plate i instelled inside the valve cover where the PVC goes into? is this a problem?
I noticed the hose from the distributor rotor button(vacumm?) was not connected to anything.
I plan on putting a EGR blocker plate, but was told it wasn’t needed to run.

So now it starts up but will not stay running idle.

Do i need an EGR blocker to run?
IS that plate needed inside the Valve Cover?
Does the hose from the Distributor rotor need to be connected?

Help…first time post.


#2

Yes, yes and yes.


#3

First off, when it idles, do you hear a sucking sound? That would be air going in around the carburetor, not through it. This will cause the truck to fail to idle. The EGR passage lets exhaust gasses back into the intake manifold so if you don’t have the ERG valve installed, or a blocker plate, it will suck air and cause this problem. The hose to the distributor should be another vacuum line that should be from the carb to the canister on the side of the distributor. Find out where it was supposed to be connected (another sucking sound) and connect it. Start it up and see if it will idle. If you still hear a sucking sound, find the spot and plug it.


#4

+1 for @keith. Be careful which vacuum hose you connect to the distributor. It must be a “ported” hose. That means it must be “0” at idle and progress upwards as the throttle is opened. A lot of “mechanics” will just connect a vacuum hose to the vacuum advance which, in effect, takes away your vacuum advance function entirely.


#5

I think the problem is the removal of the EGR. It’s a valve which – when open – connects the exhaust manifold to the intake manifold. No fresh air can get in with the valve installed. And no exhaust gas will flow into the intake manifold with the EGR installed as long as the vacuum control isn’t on (usually only during accelerations). But if the valve is completely removed, unmetered fresh air could be getting into the intake manifold which would foul up the fuel/air mixture, and exhaust gas could be getting into the intake manifold too, either of which will make the car run poorly, if at all. If the EGR is removed, that surface has to be blocked off for the engine to idle and run correctly. Be aware that removing the EGR could eventually burn the valves and result in an expensive valve job, and is also probably illegal.

The vacuum hose to the distributor could probably just be clamped off and the car would still run ok, but not as well as if it is connected correctly. But if left open it will allow unmetered air in, which spoils the fuel/air mixture.


#6

Got an older Chevy that had vac operated choke pull off. Seems previous owner had jammed a BB in vac tube to plug like since pul off diaphragm was split. Motor always would stumble/die at cold idle start. Dummy figured spending $12 on vac pull off was too pricey? So, every day, cold start was crappy?