I was wanting to rebuild the carbs on my boat because I have been told theolder gaskets can cause motor to run lean. I have heard that the plastic bowls can warp and cause problems as well. Where would they warp? What do you look for? How can I fix without replacing bowls? Thanks a lot

You are listening too much. Never seen warped bowls but can be done by over tightning the bowl screws. Gasket problem, I have seen is on the intake of 200-225 HP Evinrudes. If your motors running allright now, I would`nt mess with it.

Agreed with gary. I wouldn't mess with it!

Never seen a problem with the bowl itself outside of over tightening and messing up the gasket. The float can sometimes go bad (gum up or suck up gas and stop floating), but this doesn't occur too often. The float valve could be problematic, but this will usually mean that you leak fuel. The o-rings could also go bad if the motor had been sitting for a long time, but again you would likely be leaking fuel. Outside of that, the bowl area is usually fairly worry-free. Carb problems usually go the other way (running too rich) as a motor too lean with not run very well (or for very long).

Why do you think you are running lean? Is the motor running excessively hot? Is the motor running at all? Are you back-firing? Is the throttle hesitating or slowing down the more throttle you give it? An outboard running lean can easily spell disaster in short order (pistons can melt and seize the motor in no time). If you're worried about it, then pull your plugs and take a look at them. If they look bubbled or like they have metal deposits, then you might be running lean (the pistons are breaking down and leaving deposits on the plugs).