Carb issue????????

sikz3

Petty Officer 1st Class
Joined
Mar 25, 2006
Messages
244
Okay I rebuilt carb last spring '06 boat (would not idle) now it idles but did not cure the fact that EVERYTIME I start it I have to pump and rev engine in nuetral then jam into gear and give full throttle to take off and keep from stalling. Once the boat is moving it has no problem running okay minus the fact I have to get everyone in the boat to move to front of bow to get it to plane. Does this sound like carb issue. It also run fine on muffs in nuetral. But even on muffs when in gear I have to do the above tactics.
1980 OMC 140hp stringer 400
 

Don S

Honorary Moderator Emeritus
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Aug 31, 2004
Messages
62,321
Re: Carb issue????????

You shouldn't have to do all that, you may have to pump the trottle a time or two to set the choke and prime the engine when cold, but it should idle when you put it in gear.
Did you adjust the idle mixture correctly? Is the idle rpm too low? Has the engine been tuned up lately?
 

sikz3

Petty Officer 1st Class
Joined
Mar 25, 2006
Messages
244
Re: Carb issue????????

I have put new plugs in. What else should I try before buying ne carb? Also the only mixture screws are the two at the base of carb. How do I go about adjusting those?
 

sikz3

Petty Officer 1st Class
Joined
Mar 25, 2006
Messages
244
Re: Carb issue????????

Wewll I went out and put it on the muffs and adjusted carb to where it doesn't stall when put into gear. Now I will have to wait till I put in the water to see if it helps. Muffs are one thing, the lake is another. :p
 

Don S

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Messages
62,321
Re: Carb issue????????

I just posted this on another thread, but it was on a carb with a single mixture screw. You need to follow the basices of this, but with each screw, and both screws should be about the same, as far as turns out.

With the cable for the throttle disconnected, and water to the drive, warm the engine to operating temp, choke fully open. Hook up a shop tach so you can see the rpms while adjusting the mixtuer.
Turn idle mixture screw in till rpms drop, then back the mixture screw out till the idle is at it's highest rpm. (may have to goose the throttle a few times to keep the engine cleared out). Adjust idle speed to 650 to 700, and recheck. Once you JUST reach highest rpm and are sure that is where it's at, open the mixture screw an additional 1/8 turn.
 
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