CA77 wont return to Idle

[slopokecr]

Aloha, all those wiser and more knowledgeable than I.

1967 CA77

Problem has gotten progressively worse--when I roll on the throttle, then back off to shift, RPMs will not come down. I have tried:

1)Lubing cable/throttle/checking for kinks

2)Checked for air leaks at intake/new gaskets

3)Cleaned fuel system/Tank/carb/jets/new fuel lines (I was thinking the E10 fuel they sell here was gunking up my slide)

4)Checked to see that needle is secure in slide

Twisting the throttle with carb off but cable still in place, slide appears to return all the way down. Could my slide return spring be worn out?

Any ideas?

Mahalo, Slo

[davomoto]

Slo, try twisting the throttle with the carb bolted to the engine, and see if the slide bottoms out. How do the plugs look? Possibly advance weights sticking, but doubtful.

[Hotshoe]

How about your carb air jet, it can affect idle.
Recommended setting is 1 1/4 - 1 1/2 turns out from bottom.

[bonjour]

I would say it's an air leak.

Almost without a doubt.

Do you have much power when the RPM 'hangs' ? Is not, air leak.

You can probably also see it by taking a look at the plugs, both, or 1 , is probably white.
Wich indicates that you run lean, by probably an air leak.

Just check the plugs.

Also because you state 'the problem has gone progressively worse'

I always listen of the slides of the carb go back all the way, engine off, twist the trottle, and release, if you can hear a loud 'click' or 'clunk' then you slides are all the way back and rest on the idle screw. ( they 'clicked or clunked' against that)

You might test or ckeck your head gasket for air leaks.

Use a little water and soap, if you see bubble's forming with the engine on, between the cilinders and cilinder head, then ya got a leak there.

[FluteTears]

I would say it's an air leak.

Almost without a doubt.

Do you have much power when the RPM 'hangs' ? Is not, air leak.

You can probably also see it by taking a look at the plugs, both, or 1 , is probably white.
Wich indicates that you run lean, by probably an air leak.

Just check the plugs.

Also because you state 'the problem has gone progressively worse'

I always listen of the slides of the carb go back all the way, engine off, twist the trottle, and release, if you can hear a loud 'click' or 'clunk' then you slides are all the way back and rest on the idle screw. ( they 'clicked or clunked' against that)

You might test or ckeck your head gasket for air leaks.

Use a little water and soap, if you see bubble's forming with the engine on, between the cilinders and cilinder head, then ya got a leak there.

One of the things that I used to use for checking vacuum leaks was to spray something at the intake that would not burn and see how the engine would run and then use the same on all the air intake to find a leak. I cant see bubble's forming from an Intake air is being suck in at that point.
Dont use gas LOL
Hair spray used to work but then you have to clean that up.

[cyclon36]

I had a similar problem and it turned out to be something I would have never thought of. If you take the tank off, look at the Y-connection for the throttle cable. One of my sides after the split had popped out of its socket and was causing the cable to pull that side open just a tad.

[slopokecr]

Thankyou Gentlemen for the tips. The people on this forum are a dying breed,,,, the kind that are giving of their time and knowledge. I appreciate it.
Aloha, Slo