Full strip down

[NitroNewb]

It seems the more I do, the more I have/want to do. I removed the motor and replaced it with an O.S.While it was off I cleaned the whole thing. When I put it back together, the throtle linkage doesn't seem right. I can't get the carb to stay open the 1mm OS says. I have the idle screw all the way in.
Does the linkage have to be hooked up to get this setting or should I be able to get this with just the engine in my hand??
After looking closer,I thought the linkage was bent, so is the bottom plate and a few other things. I ordered new but I'm still unsure of how to adjust the carb to that minimum opening?? I'm waiting for parts to come in now.

Any help??

 

[Rolex]

Having it out of the car with the linkage removed is the easiest way to adjust it.
Keep gentle pressure on the barrel while setting the idle screw and looking in the carb neck for the proper distance.
If you press too hard, the screw will bind, so you might have to push/pull the barrel slightly while setting the screw.

 

[NitroNewb]

With the engine/linkage off, should the arm that the linkage will attach to still be able to go past the mimimum setting? Is the stop point set by the linkage or idle screw?
Because,as I said, with the idle screw bottomed out the barrel is still not opened enough.
Am I not understanding what your explaining to me?

 

[Rolex]

It's the idle screw that determines how far in the barrel will go. That's why I suggested wiggling the barrel in and out while turning in the screw, so you know that the barrel can't stop it from going in further.
If you're having problems with it, hold the barrel open and close the idle all the way. Then with the barrel closed, open the idle to the approximate setting. Once the engine is running, you'll most likely need to tweak that setting.

(By the way, LOOSENING the idle set screw will close the carb, and tightening it clockwise will open the idle.)

 

[Cupooterluvr]

Rolex I think he's saying that the screw is screwed all the way in yet the idle gap still doesn't change. If that's the case you most likely have a defective carb. OS should replace it free if you call them up and ask about it.

 

[3.3maxx]

it sounds to me like he is using the idle screw improperly. he is expecting the idle screw to open when the screw goes in. It just so happens to be the opposite.

 

[CharliesTheMan]

yeah I'm thinking the same thing as 3.3maxx, because the same thing happened to me when I was first starting out. It's the opposite of what we've learned all our lives about righty titey lefty loosey

 

[nitrogator]

i did the same thing if it wasn't for the pros on this site and the help they gave me i would still be adjusting stuff wrong

 

[NitroNewb]

Ok. I'm having wood floors done and the fumes have me brain dead.
I have my manual and I know that counterclk reduces opening and lowers idle.
Let's start from scratch. The idle screw is backed out all the way,the barrel is loose,it rolls round and round,engine is out of car.
Talk to me like a 5 year old.
How do I set it from here?
Rolex, I'm sure once my feeble mind does this task,I'll look back on your advice and go...Oh yea!! But for now,I don't have a clue.
I swear it's the fumes.

 

[Rolex]

I think I've figured out why you're having the problem.
On the carb barrel is a groove that the idle screw should be in. If you backed it out far enough and turned the barrel at all, it would lose it's alignment in the groove.

That groove also insures that the barrel doesn't rotate, but only moves straight in and straight out, and acts as a limiter in both directions.

gently close the idle screw and rotate the barrel around slowly while moving the screw in and out just a little. When you find that groove, the screw will settle in deeper and you will now be able to set your idle properly.

Since nothing changes when you do it now, it means that the tip of the idle screw is hitting the barrel.

Go outside and do it, where the air is fresh and crisp.

 

[NitroNewb]

That did it. Fresh air. Plus pulling the barrel out of the old carb to get a visual. I see that groove running diaganol that the idle screw runs in. I was out of it.(in more ways than one.)
Looks good now.
Thanks.

 

[jack_mcgill]

do you have a slide carb or rotary carb?? slide carb gap is 1/2 mm and rotary is 1 mm..


acutally my cvrx is a little weird too..my idle screw is all the way in and my opening is just barely the required gap...the carb is installed like it should ,the idle adjustment works but just seems to be off, like ..when the screw is bottomed,the gap should be opened well enough past the 1mm, right now its bottomed and i have 1 mm but no more..
i was thinking about shortening the spring cuz that is because of it the my screw bottoms out .it looks like that with a shorter spring my adjustment would be way more flexible..anyway ill way to get it running to see how it does before starting butchering my spring

 

[NitroNewb]

What if the idle screw is bottomed out and the opening is not enough to idle properly?
Is there any way to change this?
I'm not saying this is the case since I haven't run it yet and it looks good. I was just wondering.

 

[Rolex]

You won't know till it's running.

 

[jack_mcgill]

well the screw is bottoming on the spring so if your idle is still to slow i would probably cut the spring down a little at the time till it idles properly,but if you do this make sure that the screw aint goin to far in the carb and binds on the barrel when full open or something like that, but i doubt it does that ,O.S. engines are good quality, its probably just made like that, and remember -o.s. slidecarb pening 0.3/0.5 mm APROX
-o.s. rotarycarb : opening 1mm APROX