Mercruiser bogs only once or twice and then runs fine

[vermolen]

Thanks in advance. Mercruiser Chevy 305. New oil filter, spark plugs and new fuel water separator. Starts first try, heats up fine. Idles good and accelerates ok. When accelerating fast it will bog down and stall if I don't react. This happens once or twice only every time. Once we run it for 15 min it no longer has this issue. Carb issue?

 

[alldodge]

GM made the 305 for many years, your saying its a carb and the narrows it some but still leaves many years

Depending on the serial number its probably the choke that needs to be adjusted

 

[vermolen]

GM made the 305 for many years, your saying its a carb and the narrows it some but still leaves many years

Depending on the serial number its probably the choke that needs to be adjusted

Thank you I will come back with the year and serial number. It is an automatic choke. Will start looking online as to how to adjust. Appreciate it.

 

[rad1026]

If it starts fine at both cold and hot its probably not the choke itself but may be the choke pull off diaphragm is allowing the secondary air valve to open too quickly. Assuming its a 4 bbl carb. More information is helpful.

 

[Rick Stephens]

Adjust choke and check that accelerator pump is functioning properly. I’d consider kitting the carb if it continues.

 

[vermolen]

Adjust choke and check that accelerator pump is functioning properly. I’d consider kitting the carb if it continues.

Thank you very much!

 

[vermolen]

If it starts fine at both cold and hot its probably not the choke itself but may be the choke pull off diaphragm is allowing the secondary air valve to open too quickly. Assuming its a 4 bbl carb. More information is helpful.

Thank you very much, it is a 2002 4 bbl carb. Is there a way to adjust the secondary valve?

 

[vermolen]

Adjust choke and check that accelerator pump is functioning properly. I’d consider kitting the carb if it continues.

Would you mind letting me know how I can kit the carb?

 

[Rick Stephens]

Would you mind letting me know how I can kit the carb?

First gotta know what carburetor you have. That can be based on how many barrels, and what motor serial number is, or sometimes the tag on the carburetor. Then you get a kit for it. Kits include gaskets, needle valve that the float runs to fill the bowl with fuel, replacement check balls and assorted other little parts and pieces. Once in hand you disassemble and make perfectly clean all the inside of the carburetor. Pay particular attention to all the passageways blowing carb cleaner and air through them to be certain they are open. Depending on condition may have to chip and brush away deposits. Reassemble and reinstall. A clean carburetor is the difference between running smoothly and not.

 

[vermolen]

First gotta know what carburetor you have. That can be based on how many barrels, and what motor serial number is, or sometimes the tag on the carburetor. Then you get a kit for it. Kits include gaskets, needle valve that the float runs to fill the bowl with fuel, replacement check balls and assorted other little parts and pieces. Once in hand you disassemble and make perfectly clean all the inside of the carburetor. Pay particular attention to all the passageways blowing carb cleaner and air through them to be certain they are open. Depending on condition may have to chip and brush away deposits. Reassemble and reinstall. A clean carburetor is the difference between running smoothly and not.

ok many thanks!

 

[vermolen]

ok many thanks!

I tried to adjust the choke, but it never closed.... It stayed open from before starting, to warming up and throughout riding the boat for 15 min. It stayed open after stopping and cooling down..... I must be doing something wrong?
Engine serial 0m361340. Carb: SAEJ1223 Marine.
I attached a picture of the position it stayed in, it is not stuck....

 

[vermolen]

Would you mind letting me know how I can kit the carb?

Hi thanks a lot. Tried this but the choke never closed? Cold, hot, while running? Will order the kit but may be there is more to it? Thanks!

 

[vermolen]

Thank you very much, it is a 2002 4 bbl carb. Is there a way to adjust the secondary valve?

I am sorry, it is a 2 barrel SAE J1223 carb.

 

[alldodge]

On the side of the carb you should find numbers 861448A1 , this is your carb number.

It fires right up when cold and the choke doesn't move and stays open. This would mean its either hot all the time where your at, or the carb is running real rich.

As Rick said, need to take the carb apart and rebuild (kit it). Search using number above and you will find kits such as this one

https://www.carburetor-parts.com/Mercarb-Carburetor-Kit--PK112_p_3483.html

 

[vermolen]

On the side of the carb you should find numbers 861448A1 , this is your carb number.

It fires right up when cold and the choke doesn't move and stays open. This would mean its either hot all the time where your at, or the carb is running real rich.

As Rick said, need to take the carb apart and rebuild (kit it). Search using number above and you will find kits such as this one

https://www.carburetor-parts.com/Mercarb-Carburetor-Kit--PK112_p_3483.html

ok yes it's warm here...... will rebuild. thanks a lot