My idle screw is not long enough to set proper idle?

[bribraf]

The problem is that the idle screw is not long enough to open up the idle,it needs about another 1/8 of an inch.Is this a common problem?What should I do?I just had the carb rebuilt.It's a rochester 2 barrell 2 jet on a merc 165 straight 6 cylinder.Any help whould be appriciated.

 

[Bondo]

Re: My idle screw is not long enough to set proper idle?

I just had the carb rebuilt.

Ayuh,... Who just rebuilt it,..?? Call them,+ tell them it ain't Right...

 

[P 0 P E Y E]

Re: My idle screw is not long enough to set proper idle?

Is the screw Bass akwards?

take a real close look to see if that might be the case.

 

[dr_bowtie]

Re: My idle screw is not long enough to set proper idle?

the screw should be on the step-cam....with the choke all the way open the step-cam should be on the lowest position and the screw in half way should touch it with ease...

http://www.oldcarmanualproject.com/manuals/Carbs/Rochester/2-Jet/1964Manual/index.htm

3rd row down 1st picture has the correct location of the step-cam also called the fast idle cam...

EDIT: I would probably keep to one thread for the most help....

http://forums.iboats.com/showthread.php?t=344222

if the engine wont idle with the screw in you either have a vacuum leak or the idle mixture screws are either set right or the passages are clogged...

pull the idle mixture screws out and spray carb cleaner in them and see if it comes out the mixture ports just under the throttle blades..

if the carb is one then open the carb all the way and look down the trhoat as you spray the cleaner in the mixture screw holes...it should spray out the throat...


the mixture screws should be at a base starting point of 2.5 turns out from all the way in...then set with a vacuum gauge...

 

[ziggy]

Re: My idle screw is not long enough to set proper idle?

take a look at the cam. if i ain't mistakein. i've had the cam flip over to the wrong side. when this occurs, the idle speed screw looses contact with the cam. the idle speed screw appears to short. i don't know how it happens. to rectify it i just flip the cam back to the correct side.....

 

[jtybt]

Re: My idle screw is not long enough to set proper idle?

I don't know how relative this is but IMO you don't even need the step cam on a marine application the throttle can easily adjust the engine speed for warm up...but then, I live in Cal where we don't have a winter and I remove the choke plate on Q-jets.

 

[dr_bowtie]

Re: My idle screw is not long enough to set proper idle?

you need the step cam on 2 barrel carbs as it not only sets the fast idle but it also set the warm idle...without the step-cam there would be nothing for the screw to touch and no way to set the idle...

they arent set up like Q-jets....the fast idle cam and idle cam are one in the same thats why is it a stepped-cam...