No start after boat has been running?

[smithrock]

I have a Mercruiser 4.3L I'm having an issue with my boat not wanting to start after its been running for a while. It starts fine at first, but then after I've been running for a while and I go to re-start it doesn't want to unless I use the throttle only, but then as I go back into nuetral to engage the prop it dies? I had to turn the idle on the carb up to about 1300 to keep it from dying just so I could engage the prop to make it back to the launch ramp! Any ideas? No water in oil, engine was just rebuilt.

 

[QC]

Re: No start after boat has been running?

Engine/drive model? Age? History of this issue? All of that will help.

 

[smithrock]

Re: No start after boat has been running?

1985 Mercruiser (I believe the engine is a bit newer than an '85 though) Alpha 1 drive. Engine was just rebuilt a couple weeks ago- Runs fine except for this issue, with it not wanting to start and hold idle after an hour or more of use. after I turned up the idle to about 1300 I could get it into gear and get back. Actually had to get a jump start as I killed the battery trying to start it so much! (thanks to guy that helped me out on the water yesterday)!

I am having an issue with the remote control but thats for another thread!

 

[smithrock]

Re: No start after boat has been running?

Any ideas on what could be the problem?

 

[wellcraft-classic210]

Re: No start after boat has been running?

Could be caused by low vacuum from a vacuum leak induced during the rebuild -- This can be monitiored with a vac gauge.

another possiblity-- Dirt in float bowl clogging idle passage inlets // once you hit 1300 rpms the fuel is delivered through the venturis in the carb which iis a different circuit. The dirt may move around when flow drops off to the idle circuit causing intermittent issues.

 

[smithrock]

Re: No start after boat has been running?

OK, I'll check the carb first. Thanks!