Optimax problems

[stockcarm14]

Need help. 2006 mercury optimax 225. Suddenly started losing power . Slowed down and when trying to get back on plane it was acting as if it was running out of fuel not really a miss more like the engine was shutting off and on. So headed to the ramp but only made it about a mile before it got so bad I could only idol all the way back. Got to the ramp and it wouldn't stay running to load it. It starts fine just like it always has but immediately dies no alarms going off. Any ideas?

 

[stockcarm14]

It has a new compressor on it and my air pressure is 88 psi at the rail while cranking the engine over

 

[chillerman69]

to me, sounds like a fuel starvation problem. filter, fuel line or pump, the dreaded pressure regulator diaphram or sensor

have you replaced water separator filter on the engine? if it's not brand new as of today, pull it and inspect very good just to verify there's no restriction.

If it's sat over the winter, you may be able to shock clean the fuel and exhaust with Merc approved injector cleaner or use what everybody else does and few admit to, SeaFoam

Have heard that a failing oil line going to cylinder will cause an issue similar to yours but it's down the list of probab

 

[lafae7]

Your Low pressure fuel pump is my bet. The low pressure pump feeds the high pressure pump which it sounds like your high pressure pump is working.

 

[screwball]

I had same problem. Low pressure fuel pump cured it. they are bad to go out.

 

[jpbass]

Could be an injector on that model Optimax.

 

[BulletTJ]

If you don't run 100% gas, you need to check you complete fuel system. Ethanol is BAD for outboard engines. It will eat the inside of the fuel line up and starve your engine for fuel.

 

[benchwarmer]

A bad power pack will make them act that way as well

 

[churly]

Bad coils will do the same. Easy, cheap fix

 

[stockcarm14]

So if it was power pack or could I would have no spark correct? Also is there anywhere local that may have low pressure pump in stock? I called fish n fun they didn't.

 

[burnett1988]

I had this happen and it was a coil, and then it happened 3 other times so i changed them all and never had another problem.

 

[churly]

An '06 with a good bit of hours...change all the coils and run er

 

[stockcarm14]

So when you had a couple go bad it didn't run at all ?

 

[churly]

When you have one go bad, the boat does exactly what you describe, when you replace it, another one will go bad pretty soon in a lot of instances. Replace em all.

 

[stockcarm14]

So do you just do a spark test to find out if one is bad

 

[churly]

I guess you could, but most folks replace them all

 

[jbh3]

If your fuel line to the engine and bulb are the originals, I would consider changing them out for the newer E10 resistant material. Get a Merc bulb and line from a dealer - NOT Walmart. Change the fuel filter at the same time. How many hours on your plugs? Best way to get a proper diagnosis is to get it in to a qualified Merc tech with the proper diagnostic computer. Throwing unnecessary parts (coils, plugs, etc) at one will get expensive in a hurry and may not solve your problem.

 

[stockcarm14]

I unplugged the low pressure fuel pump and the engine does the same thing fires up and dies sounds exactly the same with it plugged or unplugged

 

[AreTheyBiting]

Lot of good suggestions here
but me personally, no one touches my Optimax except Bunch Marine
The Optimax is a killer engine but it does need proper maintenance that can sometimes be tricky
I just picked mine up from Bunch this morning
They did everything we discussed yet were honest enough to tell me when something didn't need to be done
They saved me a couple of hundred by just being honest

They aren't cheap but you absolutely get what you pay for and more

I know a lot of you prefer to do you own work, but for me, I have a place I have absolute trust in
and generally get it back fast and 100% correct

 

[TR20bh]

Island Cove keeps more parts in stock for Mercury's than anyone around. They probably have what you may need on the shelf