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1995 Mariah Barchetta 182 with 4.3LX and Weber marine carb start issues advice needed

1

1995mariahbarchettaaz

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I have a 1995 Mariah Barchetta 182 with Mercruiser 4.3 LX with a Weber marine 4 barrel carburetor. On a cold start my choke plate does not close completely. Ideally, on the first pump of the throttle shifter the choke plate needs to drop and be closed completely. For me no matter how many times you pump it stays slightly open (this is my first boat and a first one with a carb, so I am learning a lot). Because it does not close completely and create a "rich" environment in the chamber, I have to do several prolonged cranks before it starts. There are a ton of videos on YouTube on adjusting a choke plate on a Weber with an electric choke, but mine is a manual. I do not know where and what to adjust to make sure my choke plate drops after the first pump of the throttle shifter. No issues after that initial start. Any help and assistance/guidance would be appreciated. I am including a few pictures of my carb. Thanks in advance for your advice and guidance.
 

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Last edited:
In image 5703,
There is a plastic vacuum diapram with a hose attached and a link rod going to a small plate with two holes and a second link rod which is closer to diaphram.

The vacuum diaphram is a choke pull off.
The other link rod is the choke link rod to asjust. It goes further down to a bimetal spring that that rod also connects to.
You bend the rod so the choke butter fly closes more.

As the bimetal spring heats up it rotates and forces rod upwards to open choke butterfly.

So there already is a bend in the link rod just carefully bend it more to close choke more
 
kghost said:
In image 5703,
There is a plastic vacuum diapram with a hose attached and a link rod going to a small plate with two holes and a second link rod which is closer to diaphram.

The vacuum diaphram is a choke pull off.
The other link rod is the choke link rod to asjust. It goes further down to a bimetal spring that that rod also connects to.
You bend the rod so the choke butter fly closes more.

As the bimetal spring heats up it rotates and forces rod upwards to open choke butterfly.

So there already is a bend in the link rod just carefully bend it more to close choke more
Click to expand...
Thank you so much for your reply. Are you referring to the rod with I marked with the red arrow?
 

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kghost said:
In image 5703,
There is a plastic vacuum diapram with a hose attached and a link rod going to a small plate with two holes and a second link rod which is closer to diaphram.

The vacuum diaphram is a choke pull off.
The other link rod is the choke link rod to asjust. It goes further down to a bimetal spring that that rod also connects to.
You bend the rod so the choke butter fly closes more.

As the bimetal spring heats up it rotates and forces rod upwards to open choke butterfly.

So there already is a bend in the link rod just carefully bend it more to close choke more
Click to expand...
Or are you referring to this rod? Thanks
 

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There may not be anything wrong about the choke setting on your carb. Based on your description, you may just be experiencing evaporation from the float bowl...

FWIW, choke plates typically don't close 'fully' when properly adjusted.
 
makomark said:
There may not be anything wrong about the choke setting on your carb. Based on your description, you may just be experiencing evaporation from the float bowl...

FWIW, choke plates typically don't close 'fully' when properly adjusted.
Click to expand...
Ayuh,..... Exactly,.... The float bowls are empty, the long cranking is necessary to power the fuel pump, to refill the float bowls,....
'n the choke plate never completely closes,.... usually it's set to 'bout 1/8" open,.....
 
Are you following the "normal" cold start procedure?

1. Neutral
2. Crank for 5-6 seconds to prime
3. Two full pumps of the throttle
4. Throttle in slight forward position
5. Crank again to start
 
1995mariahbarchettaaz said:
I do something very similar, but instead of 2 pumps, I do 4-5
Click to expand...
You can separate if it is fuel or spark causing the hard starts by dribbling some fuel down carb before trying to start. If it starts easier, then carb prob needs rebuild or choke needs adjusting. If it doesn’t make a difference look at ignition components .in my experince if you have a real good spark the faintest amounts of gas and it will fire off.

Also as mentioned if it sits webber/ edlebrock carbs tend to dry out the carb bowls which take a while to refill.
 
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