2014 optimax stalled and compressor squeal

[StevenDavid]

I mistakenly posted this in general instead of this forum.
My 2014 250 opti with about 50 hours stalled at idle. When I restarted with throttle open some it re fired. However there is a mild squeal coming from the compressor. When I put my thumb over the brass nipple by the compressor, the squeal stops.
Any suggestions as to cause of stall and source of squeal?

Thank you

[XstreamVking]

Take that motor to a competent dealer and have it checked out. It's under warranty and needs a DDT scan and a good tech inspection to see if any faults exist, and the cause. Squeeling is never good with any moving part, especially a compressor on an opti.

[StevenDavid]

Thanks. Taking it to Dave at Markey's Marine in Key Largo, Fl. this week.

[Revolution141]

Is it belt squeal or something else?
If you mean the brass nipple on outlet side of compressor (hose from comp to fuel rail), I'd say you have a very small pinhole air leak in that nipple or the hose itself. I've had this happen several times and to the unknowing it's a little baffling and hard to diagnose at first. Basically ANY air leak in that line from compressor to fuel rail will throw out the air/fuel ratio in the rail and cause exactly what your describing to happen. Spray a little soapy water on suspect area to find source of leak.
At a pinch you can throw some fuel line on in place of existing tube to test at idle, however do not run the fuel line permanently as it can't handle the heat the compressed air produces and will fail quickly. I used to carry a pre cut length of fuel line in boat and 2 small hose clamps in case this ever happened to me off shore just to get me back.
if noise is coming anywhere from belt or pulley DO NOT START as it may be a compressor failure starting.

the opti's are a very funny beast, they will do nearly anything to maintain a smooth constant idle, even with a detonated piston or several coils disabled. However mess up that air/fuel ratio and it's a dead duck!

Good luck!

[StevenDavid]

Thank you Revolution 141,
Looking forward to the diagnosis from Markeys Marine, sometime late next week.
Steve

[StevenDavid]

Can't say enough good about Markey Marine in Key Largo. They diagnosed the issue immediately, had it repaired, plus some other warranty service issues and back in the water same day.
The problem was the factory had installed the washer on the idler arm spring assembly upside down which raised the pulley about 1/4 inch. This caused the belt to ride up and sometimes a bit over the pulley which caused the intermittent squeal. It also reduced the compressors output and that in turn is what stalled the engine.
Ran perfect afterwards. If you're ever in need of Mercury service in the Florida Keys, Dave, Andy and their folks at Markey's are an excellent choice.

[ctbassing]

Glad you got that fixed and fast