Carb Rebuild Mercuiser 4.3L

[Captain PartyMarty]

Hey Guy's

So I am getting my old boat ready to sell, so I though I would fire it up this afternoon. Fortunately it fired right up and was happy to run at 2000rpm but if I tried to pull it back to idle it would stall. After reading about the issue on the web it seems I have a classic carburetor problem "plugged idle passage". Has anybody every rebuild one? If you have where did you find the instructions? Have any of you hard carbs rebuild? How much did it cost to have done?

I guess the fuel stabilizer I put in did last year failed me...

Capt

 

[Degree of Freedom]

This is where I got my instructions...if you're carb is different they may have it...

http://www.boatfix.com/merc/Servmanl/18/18B5R2.PDF

 

[Captain PartyMarty]

Hey DOF thanks for the link, I have never worked on a carb before but the instructions seem pretty straight forward.

 

[wildthing]

hey Captain
check also the electric choke as mine on a 4BB has given up and runs to rich the mech tie wrapped it open
as i was running way to rich a mixture
say's the vent in the carb manifold gets plugged and blocked hence the chokes don't work that well .

 

[Degree of Freedom]

Hey DOF thanks for the link, I have never worked on a carb before but the instructions seem pretty straight forward.

It's pretty straight forward...take lots of pictures during tear-down. There's also an old guy who has YouTube videos you can follow...I'll try and dig those up.

 

[Captain PartyMarty]

I am starting to think I might have a choke issue with my motor. I have noticed that carburator valve is complety open all the time. If the choke is working correctly shouldn't this be closed when the engine is cold?

 

[Degree of Freedom]

with the engine off and cold the coke plate should be almost closed...there is a small gap as specified in the adjustment instructions. If it's open all the time, you've definitely got a problem with the choke.
As an FYI...carburators are very cheap...you could just drop an new one in there and be done with it.

 

[Captain PartyMarty]

Son of a.. I have messing with this thing for days

 

[MRWood]

Son of a.. I have messing with this thing for days

I feel for ya bud. Everyithing always turns into a long drawn out process unless you've dealt with it numerous times. I would consider a new one as they aren't too much dough. Keep the old one and rebuild it as a spare and learning project.

 

[Captain PartyMarty]

I figured out that as long as my choke is closed which it is now the engine runs great. As soon as the choke opens the engine stalls. I am pretty sure the carb is gummed up. It's going to be my project tommorow drain fuel tank, purge the mechanical fuel pump and rebuild the carb. If it doesn't work after than I am going to fill the boat cabin with gas and blow it sky high, then get on to working on my new boat. Always loved a good fireball in the evening

 

[Captain PartyMarty]

Just realized I am now a "Senior Member" of this site does that mean I will actually catch fish now?

 

[Gunsmith]

No but your fish will get bigger each time you talk about them.

Just realized I am now a "Senior Member" of this site does that mean I will actually catch fish now?

 

[Captain PartyMarty]

Carb rebuilt yesterday, purrs like kitten!, Boat sold today! Now I can focus on the new boat

 

[MRWood]

Carb rebuilt yesterday, purrs like kitten!, Boat sold today! Now I can focus on the new boat

That works

 

[Gunsmith]

Now in regards to the size of those fish!

That works