1977 Merc 140 stalling issues

[Newguy1330]

I have a 1977 Silverline with a merc 140 alpha 1 that is having issues. 1st it has a hard time starting. I have to pull all 4 spark plugs and clean them after every start. They get all fouled up and dark after running. 2nd once I get it started I have to give some power or it will stall. Even if I run it for 10 min with some power, as soon as I go in neutral, it starts to shake and the dies out. 3rd when I do try to put it in reverse to back out of the dock, the motor shakes and dies right away. I'm thinking I have a carb issue but I'm not sure.

 

[alldodge]

Sooted up plugs and have to keep the power up or it will die, yes I agree, it needs some carb work/replace. I would also check compression to make sure you don't have an issue there also

 

[Silvertip]

Choke is not working properly. Should be closed for cold starts and the butterfly standing fully vertically with the engine warm. A float that has sunk, needle and seat not working properly are also possibilities. Regardless, carb work is necessary.

 

[Bondo]

I'm thinking I have a carb issue but I'm not sure.

Ayuh,..... Welcome Aboard,...... I'm pretty Sure ya probably got a Carb problem,.....

Rebuild it or replace it,.....

 

[airshot]

Was having a similar issue at the end of last year, although not as severe as yours sounds. I did have plug fouling issues and idle issues and stalling issues so I did a compression check, had blown head gasket between 2-3. Had the entire head rebuilt and new gaskets...problem solved. I did know in advance my carb was good so I was comfortable with that.

 

[CaptainMak]

You didn't say when you did a tune up the last time ? Plugs, wires, cap, rotor, points, etc, fuel filter/s......
If all this was done within the year, I'd say it's time to rebuild the carby

 

[Newguy1330]

The whole motor was just tuned up last year including a carb rebuild. So I'm still at a lose. Im also being told I'm getting to much fuel and flooding it out. How can I fix that.

 

[alldodge]

Im also being told I'm getting to much fuel and flooding it out. How can I fix that.

You need the carb rebuilt again. It takes only one speck of dirt in the float needle seat to cause flooding. It could also be the last rebuild was not a quality one, don't know, just guessing here

 

[Bondo]

Ayuh,.... Rebuild the carb again, but also make sure the entire fuel system is Clean, 'n ya burn fresh clean gasoline,...

If there's crud in the tank or lines, a carb rebuild is only good til ya pump more crud into it,....

 

[Silvertip]

The engine is flooding because the carb needs work for all the reasons I mentioned. there are no shortcuts here. Is the accelerator pump working properly and did you get the check balls in the proper places. If they are wrong, fuel can flood the engine via the bowl vent tube. Is the choke working properly. If the butterfly is not opening you flood the engine.

 

[CaptainMak]

Is your choke opening up correctly? It will flood the carb out once the motor warms up due to lack of air. Also, a float incorrectly set will flood it