2003 Mercury 90HP problem

Georgetech

Recruit
Joined
Jun 25, 2006
Messages
2
Hi, Everyone
This is my problem.
a) Engine starts inmediately.
b) Idles well.
c) Rpm's go up to 5000 in neutral without any problem.
d) Leave the dock in gear at low rpm's no problem.
e) Once passed the no wake zone and I want to go I can't. Only reaches the 2000 rpm's.
Checked the three coils for spark test and found no problems,cleaned carburators,new spark plugs, new fuel filter and still have the problem. Only 86 hours in this engine. Please help! thanks George
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: 2003 Mercury 90HP problem

don't rev it over 1500 in neutral. i'm not familiar with the newer engine, when you did the carbs did you do a complete bebuild or just take it apart and clean it. if thats what you it could be part of the problem.. could be linc n sinc. lets get the newer people on this.
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
Re: 2003 Mercury 90HP problem

No load on your engine in N at 5000 so you aren't sucking much fuel. And like tas says; not good to overrev in N.

When you try to plane out, you are at the max demand point; max load on the engine; requires max BTU's (fuel) to get going.

Shouldn't be having major ignition problems with an engine that young and even if you had old fuel I doubt that it would be varnished up. Course I (we) don't know the whole story.

Go out again and when you get ready to plane out, check the squeeze bulb. If it's firm (relatively speaking; not like when you finish priming) fuel delivery is ok. But if it's soft, or caved in, you have a fuel starvation problem. Soft is toward the engine; caved in is toward and including the fuel tank.

Mark
 

Georgetech

Recruit
Joined
Jun 25, 2006
Messages
2
Re: 2003 Mercury 90HP problem

Hi, Guys
Thank you for the answers.
a) I did not rebuilt the carburators I just cleaned them an empty the bowls out.
b) I drained the whole tank a filled it with fresh gas.
c) I did test the bulb and was not soft I even squeeze it under load to make sure the fuel was going through but nothing happened.
The stator have 9 coils 6 for the charging system and the other three for the CDM's. Could it be a bad stator?
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,758
Re: 2003 Mercury 90HP problem

Remove the airbox from the carbs and when the engine acts up, squirt some fuel/oil mix into the carb. If it picks up you have a fuel delivery problem. Use a glass cleaner or similar spray bottle.
 
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