2005 Maxum 2000 SR3 Stalling on idle

[Turbo12279]

Greetings Owners.

New to this boat. Bought April this year. 05 Maxum with 5L EFI Mercruiser engine.
First few times out it worked great.
Took out on a Saturday and enjoyed the day no problems.

Took it out Sunday and starts, runs, accelerates great....back down to idle or take out of gear and it stalls.
Re start, in neutral engine runs and sounds great. Put in gear wants to stall so I have to push throttle hard to get going...goes...once I slow and try to idle stalls again.
On docking, try to reverse, stalled.

Did some research, possibly idle interrupt switch
MArina says I need a tune up, want to put new plugs, dist etc.....say that it is corroded.

Any assistance is appreciated

Wayne from Cambridge Ontario

[Phillbo]

If the boat is new to you a tune up may be a good idea. I'd start with having the IAC tested to see if it is functioning as expected.

[Turbo12279]

Thank you...what is an IAC

[mmwjr]

Originally Posted by Turbo12279

Thank you...what is an IAC

Welcome aboard

IAC idle air control valve. It adjusts the amount of air at idle, less air when engine is cold to riches the mixture, acts like a choke. If faulty the engine will have trouble running at idle.

Shift interrupt switch shorts out ignition when coming out of gear only. This is to remove load from dog clutch to lessen wear coming out of gear.

Tune up seldom hurt unless you know it was done recently, yes a bad dust cap will cause a bad idle and even across the power band.

[shrew]

Moved thread from "Forum Support | Suggestion Box | News" to "Engines"

Welcome aboard 'Turbo12279'!!!

[Turbo12279]

Thank you all for your responses.
I had a tune up done, they changed the plugs, distributor cap and rotor. They fired it up and it worked fine while cold but once the engine warmed up it continued to stall.
So now (even though when I initially called them I told them it was the IAC) they are going to change the IAC (175$ + 30 mins labour).
I contacted the former owner who had the boat since new...he never had a tune up. He brought it to the same shop every winter and told them to do what it needed, they never did anything but oil changes and winterize.

[Phillbo]

You may want to buy the part yourself and take it to the mechanic to have it replaced (or do it yourself. it's not hard).

They are bending you over on the price of the IAC. If I remember right it can be had for right around 80.00

[mmwjr]

The IAC is about $100 US dollars. I doubt they would install one you supplied.

[Phillbo]

I'd find a different mechanic that won't rape you on parts and time. The IAC is a 10 minute job but I assume 30 minutes is his minimum bill.