350 mag won't stay running

Willhound

I'm puzzled by this part. " I no longer have to press the button to shift out of neutral for forward or reverse."

You shouldn't have to. The button just releases the shift cable so you can give it some throttle without being in gear.
Is your cable out of adjustment? That could even possibly affect the engine running. On a lot of models with electronic ignition the ignition will momentarily cut while you shift to ease the clunk. So quick you won't even really notice.

halifax212

@Willhound , the thumb button on the grip, not the one at the lever base.  Going to have to dig in a bit further but for now it is operational and the weather is perfect here on the coast. Come visit to escape the coming "heat dome"

Dude_Himself

The broken shifter or linkage out of adjustment would prevent the engine from starting and also possibly not require the thumb button to shift.

Willhound

"the thumb button on the grip, not the one at the lever base."
Aah! Got it. My 2000 single 270 doesn't have that. Trim switch is there.

rasbury

me to, that was throwing me...I push in the round button to idle up without putting in gear...

halifax212

ok so I am back on the water after replacing the failed IAC valve. The local shop said to simply purchase the automotive one(he ordered it for me) for about $90. The only thing now is I find the idle high, around 800 rpm sometimes closer to 1000.  Pretty sure idle was 600 before the repair.  My question is since I fixed the problem and cheeped out with the auto part rather than Mercruiser at $240 plus tax , would this be affecting  my idle?  The OEM is a little different looking inside at the valve. I will spend the money for OEM if helps.  The higher idle makes shifting in and out of gear not as smooth.

randy56

Slow down the idle, to 800 rpm, easy to do. I't s not good on your outdrive at 1000 rpm. 

rasbury

Pretty bad I would think..

halifax212

Agreed guys. Will swapping out for the mercruiser IAC do the trick or can a service centre  simply adjust it down?

randy56

you can do it yourself, and second thought, 600 is about the lowest but works fine as long as it stay's running in gear, 800 is the highest you want. 

GMSLITHO

I think the throttle body is set as far as adjusting the idle I had the same issue I put one in from the auto parts store .I think it was the same as a Ford Taurus ...... any way the idle did seem high then I replaced it with the omc  one and it did make a difference 

halifax212

@GMSLITHO   , thanks. I think I will do that today.  I'll just have to reel in a couple extra print jobs this morning to cover it haha.

GMSLITHO

Slow summer down here 

halifax212

Problem solved. Purchased the Quicksilver IAC and my idle is back down to 650rpm from 800/900. Everything is back to normal.  Thanks @GMSLITHO for advising me to go for the OEM part. Totally worth it.

GMSLITHO

I only know because I tried the Ford IAC and had the same problem ,but other people have used it and no issues