2 beep alarm boat will not start

• Aug 15, 2022

• #1

B

Bretko23

New Member

May 9, 2018

24

Bridgeport, NY

Boat Info

225 weekender 2002

Engines

5.0 MPI Mercruiser

Hello folks. 5.0 mercruiser MPI here. Cruised fine until we got 2 warning beeps with an interval of a few minutes then 2 more beeps (warning) arrived at destination now boat will not start. I can get her to run if i "rev" throttle arm but as soon as I return arm to neutral position she dies.fluids are all up to snuff and brand new gas.....Help if ya can!!!!!

 

• Aug 15, 2022

• #2

techmitch

Well-Known Member

May 1, 2008

8,395

Chesapeake Bay, Middle River/Frog Mortar Creek MD.

Boat Info

1999 270 DA

Engines

Twin 4.3s W/Alpa I Gen II's

Sounds like the classic bad IAC valve.

 

• Aug 19, 2022

• #3

Bama Boat

New Member

Jul 26, 2022

18

Boat Info

1992 300 weekender

Engines

Twin 5.7 mercruisers

What is the IAC value and what does it control or do?

 

• Aug 19, 2022

• #4

S

scoflaw

Well-Known Member

Aug 10, 2011

6,395

cape cod mass, cape coral fl

Boat Info

1999 Powerquest legend 260 sx 502 mag
2005 Baja 242 islander 496

Engines

502 mpi Bravo 1
496 mag B1

Lets air into the engine when the throttle blades are closed.

 

• Aug 19, 2022

• #5

ColoSR

Active Member

Apr 25, 2018

425

Boat Info

2003 Sea Ray Sundeck 220

Engines

MX 6.2L MPI Mercruiser with 2.2 Bravo III drive

If you can’t get a hold of a Merc IAC valve, the Standard Auto AC423 model fits. You can pick those up from the auto parts store. Lots of YouTube videos of Merc 5.0l IAC replacement. Is a pretty simple job.

The ac423 comes with the wrong gasket, so you need to get some silicone rtv when you are at the store