outboard cutting out? - The Hull Truth

tterrien · 07-19-2008, 07:07 PM

02 Mercury 200 Carbed runs great but it seems after running a while it does funky things. Runs great at 4000 rpms then if it drops down to say 3000 rpms it starts cutting out and bogging like it isn't getting gas but if I throttle back up to 4000 it takes off and is fine. If I don't throttle it back up it will bog right down and stall as if the gas supply was cut off. Starts right back up and runs fine as long as it is up at 4000. Seems like it is only after running a while say maybe running for 15-20 minutes. I am stumped on what it could be. Please help.

Thanks

welder · 07-19-2008, 07:13 PM

Dirty carbs, they need to be taken apart and cleaned

capt. thunder · 07-19-2008, 07:21 PM

It might be water in the gas.

Kamper · 07-19-2008, 07:41 PM

6 years? That's a reasonable time to clean and "rebuild" the carbs. Rebuild kits are usually less than $30.

If you want to cheat a little, you could drain the bowls, then blast the jets from the venturi. Refill the bowls and repeat a few times. I guess you've got a 50/fifty chance this will clear out any crap that might be causing trouble.

You can also remove the bowls and pull the jets for cleaning. Those gaskets will probably be okay for reinsertion but the bowl gaskets I wouldn't want to bet on.

You might also want to check the floats in the carburetor. Metal floats sometimes develop stress cracks and nylon floats absorb fuel. This leads to flooding so probably not your problem today but they sometimes need to come off to expose the jets. A slight shake is all you need to feel if there is fuel in them. There are small pins and other bits involved so be gentle and watch where they go.

I only dis-assemble one carb at a time. I have a manual but if I get confused I have a completely assembled example to refer to.

The suggestions about checking your filter for water and replacement are valid too.

Good luck!

tterrien · 07-19-2008, 08:59 PM

Thanks guys for the help. Any idea of the cost or resonable cost to rebuild the carbs? The water seperator didn't have any water in it but with the new gas I am wondering if it is partially from the gas because I sometimes don't use the boat for a couple of weeks so maybe the gas is going bad.

capt. thunder · 07-20-2008, 06:16 AM

Gas won't go bad in a couple of weeks. The best way to test for water contamination is pouring some of your boat gas into a clear glass jar. The water will separate from the gas. If water is present, try adding some e zorb or some other water absorber in your tank. If this isn't the problem. it's probably the carbs.