engine too lean?

bogeyrider63

Cadet
Joined
Jun 23, 2009
Messages
13
Hi, i have a 1989 celebrity 181 with a 4.3 litre. when going back to neutrel engine wants to stall out. i think it is running too lean but i can't find the adjustment on the carb. can someone tell me where the adjustment screw is on the carb? thank you. and which way to turn screw for leaner or richer?
 

Haut Medoc

Supreme Mariner
Joined
Jun 29, 2004
Messages
10,645
Re: engine too lean?

Stalls out or wants to stall out?..... :confused:
Either way, if it runs good while in gear, the problem is likely your lower shift cable, (which actuates the shift interrupt switch), rather than any fuel type problem....;)
 

Bt Doctur

Supreme Mariner
Joined
Aug 29, 2004
Messages
19,349
Re: engine too lean?

If the shift interupt is actvating, it`s a sign of a bad lower cable.
Haut, have you run into any carbs with a green copper colored moss like material in /on the venturi tubes clogging them shut.
Have had 2 so far.
 

ken_23434

Petty Officer 1st Class
Joined
Jul 28, 2008
Messages
313
Re: engine too lean?

Welcome to the forum.

The top thread on this forum titled "--Adults Only--" has a lot of links to various threads to solve common problems. There is also a link to the genuine Mercruiser Service Manuals there (free download). Download the one for your engine and the one for your outdrive. Apparently, there have been some issues with the downloads being available lately, though.

The manual for your engine should have all the info you need about your carb adjustments.

But, to answer your question about what direction to turn the screw, counter clockwise (out) will richen the mixture. I have a different motor, so I do not know where the mixture screws are for your application.

I hope this helps.

Ken
 

bogeyrider63

Cadet
Joined
Jun 23, 2009
Messages
13
Re: engine too lean?

throttle control cable was replaced last summer as engine would backfire when going full throttle to pull tubers. took care of the backfiring, but it wants to almost stall when going to neutrel.
 

Haut Medoc

Supreme Mariner
Joined
Jun 29, 2004
Messages
10,645
Re: engine too lean?

throttle control cable was replaced last summer as engine would backfire when going full throttle to pull tubers. took care of the backfiring, but it wants to almost stall when going to neutrel.
Throttle contol cable & the lower shift are two different things....
Or.... it might need adjustment if the switch is slow, or possibly need some lube at the shift plate....
BT.... No, we don't have moss out here......:D
Again, if it is only an issue when shifting out of gear, leave the carb alone or you will cause uneccessary problems......;)
 
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