Correct Diagnosis - carb rebuild?

jim.bresee

Cadet
Joined
Sep 5, 2005
Messages
7
The patient is a 1993 Larson 201se with a Volvo 501b DP drive.<br /><br />History - motor over heated last year when the raw water hose elbow broke on the outdrive. Motor replaced with remanufactured engine from Vesuvio.<br /><br />These are the symptoms that existed on the old motor, and now the new motor:<br /><br />1. After warm up, 50% of the time the engine will not start shortly after shut down. Leaving the throttle wide open and waiting 20 minutes and it will restart 100% of the time. Suspect flooding, but don't see fuel flowing into the carb after shutdown.<br /><br />2. About 50% of the time, the boat will stumble and bog when pushed onto a plane (for example, pulling a water skier up). Once on a plane and RPM builds up, it runs smooth.<br /><br />I've swapped the raw water fuel filter.<br /><br />I do not believe the carb has ever been rebuilt.<br /><br />Questions:<br /><br />1. Am I on the right track with the diagnosis?<br />2. I am a reasonable mechanic (work on old Audi's and my Miata - I've done jobs like timing belt replacements, etc). I have not ever rebuilt a carb - how bad is it to rebuild a holley 4 barrel marine carb? Is it something a shade tree mechanic can do, or should I send it out?<br /><br />Thanks!<br /><br />Jim
 

Scaaty

Vice Admiral
Joined
May 31, 2004
Messages
5,180
Re: Correct Diagnosis - carb rebuild?

Sounds like you are right on track, Get a kit and rebuild, or send it out. Not difficult. Just make sure you do a good cleaning of ALL the tiny little passages in the carb.
 

f_inscreenname

Commander
Joined
Aug 23, 2001
Messages
2,591
Re: Correct Diagnosis - carb rebuild?

Sounds like a fuel problem to me. I am thinking for the stumbling the accelerator pump is bad or your floats are wrong. Either way its the carburetor. Especially if you transfered the carburetor from the old motor to the new one and it is doing the same thing.
 

jim.bresee

Cadet
Joined
Sep 5, 2005
Messages
7
Re: Correct Diagnosis - carb rebuild?

Is it really picky to re-set the carb after a rebuild?<br /><br />I've read about setting the carb via vacuum gauge.... I assume there is an automotive port that is plugged that you jack a vacuum gauge into, right?<br /><br />Thanks,<br />Jim
 
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