Engine idle surge

[CODI]

Well...here I am again. This time not for the distributor! The one I got
seems to be working fine. Now I am having an issue with the engine
surging. It only does it however, after the engine has been revved up
and I am backing the throttle back down to idle. One I get it down on
idle, it starts to sure but usually will go away after a few minutes. It
runs great under a load and once I get the RPMs up to about 800.
Grant it, it does sputter a little, but it has done that somce I have had
it. Any ideas what is going one?

 

[David G]

Richen the idle mixture up 1/2 turn and see what happens.

 

[CODI]

I was kinda thinking that could be the issue. Out richens, right?

 

[Royse]

When it does that, pull the choke out a bit.
That will enrich the mixture so you can see if it helps or hurts.

 

[R Geiger]

The idle jet adjust is an air adjustment. out would lean the mixture.

 

[JMOR]

I don't intend to sound like I'm jumping on anyone, but it really doesn't matter which way the screw turns for rich or lean, we are just looking for the position that it runs best aren't we?

 

[JMOR]

(quoted from post at 23:17:54 10/18/15) I don't intend to sound like I'm jumping on anyone, but it really doesn't matter which way the screw turns for rich or lean, we are just looking for the position that it runs best aren't we?

.e., don't get trampled by the elephants while looking for ants to stomp!

 

[GB in MT.]

[b:dc6782122a][i:dc6782122a]

Try this......:



Gary[/i:dc6782122a][/b:dc6782122a]

 

[R Geiger]

But sometimes it helps to understand what is going on.

 

[JMOR]

(quoted from post at 23:31:38 10/18/15) But sometimes it helps to understand what is going on.

t is always best to understand how things work, for sure! But some/many get lost in the details instead of finding a means to the end result sought. Another good example of what I'm speaking of is beating them selves up trying to get timing down to the degree or two, when close is plenty good for an N engine, which will never know the difference +/- 5 or even more degrees.

 

[Dell (WA)]

Codi........NO, the side-pointing idlemix is OUT fer LEAN, IN fer ENRICH. Simple, eh? .......HTH, Dell

 

[R Geiger]

I totally agree that some do get way too deep about some things. They get so involved in the details that they lose sight of the problem.

 

[CODI]

Nothing seems to help it. Out, in... Doesn't seem to matter. I am getting good flow through the carb and all filters look clean. There seems to be no problem above 900 rpm, however the main adjustment is adjusted extremely rich. Im thinking there is a vacuum leak somewhere....???