Bogging/stalling issues

kay

Cadet
Joined
Jul 31, 2007
Messages
10
I have a Merc 40 Thunderbolt that seems to have some issues...When i first took it out,it would start rite away but i could only go into trolling speed.If i gave it more throttle...it would die.But now...i`m having a hard time starting the motor.I`m thinking it needs to be tuned.Maybe running too rich?Also...when i opened her up, I found out some of the plastic from the choke had melted onto the carburator(see pic).Any reason what could of caused this? Looking at one of the pictures...theres a hose running on top of the carb( i think it`s coming from the float) that had a crack underneath.You guys think that had something to do with melting the plastic?Thanks!!!
 

Attachments

  • 73007 002 revised2.jpg
    73007 002 revised2.jpg
    87.5 KB · Views: 0

Laddies

Banned
Joined
Sep 10, 2004
Messages
12,218
Re: Bogging/stalling issues

It looks like the engine may have backfired and started a carb fire, the backfire was probably caused by the lean condition that wouldn't let the engine run at full speed, you need the carb cleaned and the choke parts replaced
 

kay

Cadet
Joined
Jul 31, 2007
Messages
10
Re: Bogging/stalling issues

Sorry for the late response or update. I took the carb apart and cleaned it. I found the problem of it bogging... I forgot to ground one of the wires for the ignition. I think thats why it was bogging. Started her up and did a little tuning with the muffs on and she works great now. I just need to get her into the water to tune her with load. I did check the compression and both cylinders are around 155psi each :D. I also replaced the hose that was on top of the carb as it was dry rotted. I think the melted plastic was a piece of the choke assembly. Not too bad as i think it was only $7 to replace it. Thanks for the suggestion...
 

geb

Seaman Apprentice
Joined
Jul 24, 2007
Messages
37
Re: Bogging/stalling issues

Sounds like you got it going fine. Not meaning to hijack thread, but the photo of the carb reminded me of a question. This is for the experts about the tubing that runs across the top, that's for some king of fuel conservation of some sort I think. I've read here about putting a bb to plug it. Is that a good recommendation to follow? And are there really any benefits to plugging it or not? Thanks

geb
 
Top