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Help me adjust my carb float :)

T

tauket2

New member
Hi all,

i have a mercruiser 3.0 and am having issues with hot start. the probable culprit in my opinion is the float level.

I've never taken my carb apart so i'm turning to you guys to make sure i don't miss a step. i tried to find videos so i could visualize the procedure but i didnt find much.

i used to think i had a Mercarb, but the presence of two idle adjustment screws leads me to beleive it is a rochester 2 jet.

from what i understand, all i need to do to access the float bowl is remove the air horn.

once i've gained access to the float bowl, how exactly do i go about adjusting the float height? where do i measure?

do i need to take the carb off the engine completely to accomplish this or can the carb stay on the engine?

i'm hoping i can do this this afternoon

cheers and thanks alot in advance

chris
 
Untitledccjpg.jpg

Untitledcc1.jpg
 
Thanks for the diagrams! very helpful!!!

here are some pics of the carb.

i also noticed the whole inside of the top of the carb is wet with either oil or fuel.

the flame arrestor also has some although it isn't dripping wet, enough to get some on my fingers.

what does this mean?

cheers

carb1.jpg
carb2.jpg
carb3.jpg
 
I had the same problem with my 3.0 most likely flooding over due to float needle not seating.I would buy a new float and needle and seat. Mine has been perfect after I replaced that stuff on mine.

i have a mercruiser 3.0 and am having issues with hot start. the probable culprit in my opinion is the float level.

I've never taken my carb apart so i'm turning to you guys to make sure i don't miss a step. i tried to find videos so i could visualize the procedure but i didnt find much.

i used to think i had a Mercarb, but the presence of two idle adjustment screws leads me to beleive it is a rochester 2 jet.

from what i understand, all i need to do to access the float bowl is remove the air horn.

once i've gained access to the float bowl, how exactly do i go about adjusting the float height? where do i measure?

do i need to take the carb off the engine completely to accomplish this or can the carb stay on the engine?

i'm hoping i can do this this afternoon

cheers and thanks alot in advance

chris[/QUOTE]
 
..."I have a Mercruiser 3.0 and am having issues with hot start. "

Of course you are, for the carb is siting on top of the exhaust manifold with this setup! That causes percolation of the fuel after shut down. On my old 19 footer, I used to pull the doghouse forward, and let the motor idle for 5 minutes, after a hard run. That lets the carb and etc. cool down, which reduces percolation.

Jeff

PS: Electronic fuel injection on these otherwise excellent power plants would cure that problem completely, but the four cylinder setups tend to be used in 'entry level' boats, which means EFI would be too expensive (apparently).
 
2X on the installation and operation.....

In addition to Jeff's open the hatch suggestion, you can go to a fast idle for a few minutes before you shut off the engine to help get rid on some of the heat.....and doing the restart with the throttle half way open can help in some cases, too...
 
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