350 Mercruiser Fuel Problems at idle but high spped works

I have 2005 350 with Bravo drive (OW619043). Several weeks ago, I started having fuel problems. The motor died on the lake and wouldn't stay started. A "MerCruiser Certified Technician" told me it was the Fuel Pumps (high flow pump most likely). Come to find out it may have only been one gas tank empty and the other was a stuck anti-syphon valve (after spending $600 on new fuel pumps and THEN checking other stuff...). So replaced fuel pumps, replaced anti-syphon valves and ran fine for 3 weeks now. This past weekend the the boat wouldn't run at idle (I could get it started by running the throttle up and then quickly and gracefully hitting neutral and gear to get going). but the 2 beeps per minute warning continuely goes off - even after shutting off and restarting same way. Looking for Any ideas on what to check next. I am somewhat handy but not sure what else to check and don't want to put the boat in the shop for an undetermined amount of summer! Thanks in advance!

Re: 350 Mercruiser Fuel Problems at idle but high spped works

If you can, get someone to hook up a code reader to see if there are any error codes registered. Better than just throwing parts at it.

Re: 350 Mercruiser Fuel Problems at idle but high spped works

r.j.dawg said:

If you can, get someone to hook up a code reader to see if there are any error codes registered. Better than just throwing parts at it.

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Sir, I have a 2005 Playcraft Powertoon. Any idea where the plug-in for the code reader would be (back on the engine or under the console)? Just wondering where to start looking.

Re: 350 Mercruiser Fuel Problems at idle but high spped works

Fuelish Pleasure said:

Sir, I have a 2005 Playcraft Powertoon. Any idea where the plug-in for the code reader would be (back on the engine or under the console)? Just wondering where to start looking.

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Ayuh,... Welcome Aboard,.... It's on the motor... near the 'puter...

Re: 350 Mercruiser Fuel Problems at idle but high spped works

You have an IAC Idle air control valve on the intake manifold, these are notorious for going bad and causing poor idle at low RPM. If you go to BAM marine ans search your engine by serial number you can locate where the sensor is. If you are savy enough you may take the mercruiser number and cross it or call mercruiser directly and ask what GM part number it is. Mercruiser does not make the sensors they purchase them either through GM or Bosch. Then you may locate the IAC at a local parts store and save yourself a lots of money. My IAC was made by ford motor company cost me 1/2 the price of the mercruiser part. Again BAM marine then search with pictures locate your engine by serial number and look through the parts list.

Re: 350 Mercruiser Fuel Problems at idle but high spped works

Here is the link http://www.mercruiserparts.com/Show...1681&bnbr=100&bdesc=Throttle+Body(Mechanical)

the part 862998 crosses to Standard AC423, however verify this.

Re: 350 Mercruiser Fuel Problems at idle but high spped works

Thanks for the info! Seen that same thought on another thread to a fuel problem and ordered the part (sadly...already ordered from Mercruiser...sigh!).
Also, just FYI... it is REALLY difficult to get boat repair shops to agree to just "stop by and read the codes for you".... they all want your boat for 2-3 weeks before "they can possibly get to it". WHAT a racket!

Re: 350 Mercruiser Fuel Problems at idle but high spped works

Many, many thanks to all for the help and advice! Boat will be on the water this weekend! IAC did the trick and she runs like a dream! Fuel Pumps, filter, anti-syphon valve, and IAC. Anything else I need to watch for? (not sure how much regular maintenance was done on the boat. 2005 Playcraft Powerton 2600 with Mercruiser 350 MAG MPI. Thanks again!