So i've been having a problem with my mercury 90 4 stroke. It starts but will die immediately under throttle. A few weeks ago i took all the carbs off, cleaned extensively (done by my friend who is a car mechanic). Put everything back together and it ran but only with the idle screw tightened too much and would stall under throttle. Frustrated, i brought it to a boat mechanic. After waiting two weeks for it to just be looked at i went by to check up on it today and they happened to have it out working on it. I asked what was wrong and they said the carbs were dirty...I told them that that can't be because i had just cleaned them and it sounded like a vacuum tube or something was off. They insisted that the carbs must be dirty and it was only running on 2 cylinders...I found that odd since when i took the intake off i saw gas being sent through the first 3 carbs but not the last one (which changed after i cleaned it). The boat mechanic said that the carbs have a bunch of intricate parts and they need to be taken apart (which we did).
Did i miss something? Long story short, when they said carbs i told them to stop what they were doing and i would pick it up tomorrow. They also quoted the carbs at being $1000 worth of work just to clean.
Any thoughts from more experienced boaters? Are boat carbs that much different than carbs on a motorcycle or a car? Is there any special thing to look while cleaning? I made sure to follow the cleaning process in the mercury 90 manual.
The mechanic did say something about balancing...which I do see as being a possibility as to why they aren't running correctly (but i do NOT think they are still dirty). Any thoughts? Can you balance carbs on the assembled engine or do i have to take it apart again?
Did i miss something? Long story short, when they said carbs i told them to stop what they were doing and i would pick it up tomorrow. They also quoted the carbs at being $1000 worth of work just to clean.
Any thoughts from more experienced boaters? Are boat carbs that much different than carbs on a motorcycle or a car? Is there any special thing to look while cleaning? I made sure to follow the cleaning process in the mercury 90 manual.
The mechanic did say something about balancing...which I do see as being a possibility as to why they aren't running correctly (but i do NOT think they are still dirty). Any thoughts? Can you balance carbs on the assembled engine or do i have to take it apart again?