I have taken this answer from my Haynes Repair Manual (so as not to screw it up with misinformation):

"The PCV system operates by drawing in air and mixing it with the vapors which have escaped past the piston rings (blow-by vapors). This mixture is then drawn into the combustion chamber through an oil separator and PCV valve."

Anyhow, it looked from your picture that you do not have a PCV valve in the hose going from your passenger side valve cover to the carb base plate. The PCV valve is a small silvercylinder, like a short stack or quarters andoperates asa one way valve.

Perhaps your lack of the PCV valve is causing a vacuum leak, and thus affecting your idle? I think Autozone has the PCV valves for about $7. You can always try plugging the valve cover side and seeing if that has any affect. (It might not.)

-EDIT- I just went back and looked at your photo again, and maybe you do have your PCV valve at the very end...is it painted blue?! Check it to see if the "ball valve" is stuck in it.

 

After reading this thread and your issues with the difference between idle sped in gear, and idle speed out of gear, I wonder if you might have a vacumne leak? Probably not a huge one, but big enough to throw off the fuel / air ratio.

The large disparity between in gear and out of gear idle speed makes me think that you might be running way lean. This could be caused by a vac leak, or as mentioned, possibly a defective PCV valve, which is also a de-facto vacumne leak.

<<also, this would explain the hesatation you are experiencing.>>

 

The difference between "in gear idle" and "out of gear idle" should only be about 200 RPM if everything is right and you are not running a wild cam.

The outlet in the spacer is for PCV, if you alraedy have PCV plumbed into the base of the carb, you will need to block the outlet in the spacer.

 

so say I get rid of the hose, i was looking at the new spacer I ordered and it does not have an inlet/outlet what do I do with the hose then?

the outlet for the spacer in connected via hose to the valve cover. i used the vaccume port on the carb to test for a leak and noticed nothing for the carb, so maybe it is in the line, I guess we'll see when I get my new spacer.

Like I asked above, what do I do with the hose after I put on the new spacer?

 

I have not used or even looked at a Holley carb in many, many, years. I like them ant they had been good to me in the past but I just hae not used one letely. That said,,, for my disclaimer, Many carbs already have a PCV port built onto the bottom of the carb. I dont know if your carb has one or not, if not you will probably need to get a spacer with an outlet for the PCV.

I am nearly certain that your condition is being caused by a lean condition, I cant say if it is a carb issue, or a vacumne leak. You might try the carb cleaner trick where you spray the carb cleanrer sparingly around the intake to head gaskets and the carb to manifold gaskets and see if the tone or speedof the engine changes.

Be aware of the remote possibility of a flash fire, and be ready to deal with it if needed.

 

If your carburetor does not have the capacity to hook up the PCV hose to it's base, then you are going to need to buy a spacer with that ability. You cannot get rid of the hose and the PCV system otherwise you will cause internal damage to your engine over time.

 

Yes, you need to run a pcv system. Also, are you sure all the vaccum ports on the carburetor that you aren't using are plugged? That'll give you a vaccum leak(which it sounds like you have after the way you described how it drives).

 

Good advice soaring, that's exactly how to adjust any carb that's working correctly.

 

HI grruminator78,
Back in the days whenI was tuning-up cars for a living,I ran accross your scenaio on occassion. There are a couple-o-three things going on with your carb:

1. You can't adjust the idle speed correcly.
2. The right idle circuit is ineffective.
3. The engine bogs when you step on the throttle.

All are related to the fuel system and most probably the carburator/intake system ( although a clogged fuel filter or bad fuel pump will cause a bog down on acceleration). If the right screw doesn't affect your idle quality, noticeably, you have one of the conditions noted by everyone else ( acumn leak, plugged idle jet circuit, transfer ports exposed).

The PCV system is there to recirculate the hydrocarbons from piston blow-by back into the intake for further burning. The hoseshould be hooked up to an adapter plate under the card or a port off of the manifold and the other end stuck in the engine valve cover thru a rubber grommet of some kind. To check if it's bad, put your finger (thumb) over it and see if the rpm really rises (like 500 rpm or so) with the engine running. If it really increases, then the valve is stuck open - Replace it. If not, then plug off the PCV valve and see if you can adjust the right idle screw. If not, then there's another vacumn leak or the carb is in need of an overhaul. The previous posts tell you how to check for vacumn leaks. I 've also seen bad power brake booster diaphrams causes a lean condition in half of the cylinders. If you have PB, take the hose off of the PB booster and plug it off. If things get better- that's your problem (change the booster/hose/ checkvalve).

It was normal in the 60-late 70's for the idle to drop from about 700-850 rpm to about 550 -650 rpm when theTrans was put into a drive gear ( R,D,2,1). Thats why you set the timing and the carb idle speed/mixture whilein drive and with the vacum advance hose plugged off of the dist.

Once you fix your carb problem, the idle bog may go away, if not go to the holley website and download their manual on your carb, it has some good info in it.
Good luck