Alpha One starts but won't idle

[bluebit88]

My '92 Mercruiser Alpha One 4.3L would start for a few seconds then stop unless I keep pumping the remote control throttle.
I rebuilt the carburator but the problem did not go away. When I manually pump the throttle I can see two fuel jet streams to the venturi.
Could someone help. Thanks.

 

[Bondo]

Re: Alpha One starts but won't idle

I rebuilt the carburator but the problem did not go away.

Ayuh,.... So What did things Look Like when you had it apart,..??

It sounds like it might Still be the Problem.....

 

[CharlieB]

Re: Alpha One starts but won't idle

Sorry, but the idle passages and/or the air bleeds are still dirty, the idle speed is set too low and/or the idle mixture is wrong.

All need attention to make things right.

 

[Don S]

Re: Alpha One starts but won't idle

I rebuilt the carburator but the problem did not go away.

How did you rebuild it? Did you completely dissassemble the carb (Including the accelerator pump check ball spring and T retainer), soak it in carb cleaner, and blow out the passages with compressed air?

 

[bluebit88]

Re: Alpha One starts but won't idle

I completely disassembled the carb, yes including the accelerator pump check ball spring and T retainer and soaked in carb cleaner but did not blow out with compressed air. How long do I have to soak it?
Thanks for your reply.

 

[Don S]

Re: Alpha One starts but won't idle

How long do I have to soak it?

No way of knowing the answer to that question. Depends on the quality and type of the cleaner. But if you didn't blow them out with air, then you wasted your time. It's all still in there and rehardened.

 

[Coors]

Re: Alpha One starts but won't idle

Gunk costs big $$, but it works. Overnight. Compressor needed.

 

[Coors]

Re: Alpha One starts but won't idle

And sometimes a small strand of copper wire is needed. not steel wire, soft copper.

 

[Maclin]

Re: Alpha One starts but won't idle

A spray can of carb cleaner with one of those red small tubes can be used to blow out passages, but be careful as that little tube really ups the pressure and the stuff will come out holes you may not be expecting and can get in your eyes and other inconvenient places. You need to be careful with compressed air as well.

 

[bluebit88]

Re: Alpha One starts but won't idle

Finally got time to work on my boat again. I reopened the carb and soaked everything overnight, and this time I also used compressed air to blow out the passages as suggested, reassembled everything back and started the engine...it's working!! Thanks for all your help.