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01 Honda 90 runs good but dies when given gas on the water

wcc47

New member
I just cleaned the carbs and it now runs but when put on the water it bogs and dies when giving it throttle. I'm guessing there is a jet or passage way on the carbs that i missed. They were very dirty and clogged from sitting. Just wondering what to look for because I guess I'm going to pull the carbs again and try to clean them better. I did pull all the jets and spray the carbs plus blew with them out with air compressor. Is there something else I should do? I was also wondering if 2 1/2 turns on the idle valve is correct as this is what I have them set at. Thanks for any help or suggestions.
 
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The first thing to do is a cylinder drop test. You may have an issue with only one carb.

With the motor running at idle, use an insulated pliers to pull the spark plug wires off each spark plug one at a time. As you pull each off, the engine should reduce slightly in speed. Then put the wire back on. If you get to one and the engine speed does not change, you have found the carb with the issue.

This does not mean that they all still do not have issues.

The idle mixture screws should be set initially at 2 1/4...so you are close. That should not keep the engine from running.

If you did not flush the fuel system while the carbs were off, you may have picked up some debris or pieces of fuel line that is deteriorating. Today's fuel is starting to each up the fuel lines and the pieces go into the carbs.

I would say take off the carbs again and pay close attention to the slow jets (#40), the main jets (#39), and the idle jets (#18). Most likely, the idle jets are plugged. If they were as bad as you said, you should just replace them. They also develop very small cracks that allow them to suck air and work incorrectly. They are impossible to check to see if they are clean because of the ledges inside the two tubes that make up the jet.

http://www.boats.net/parts/search/Honda/Outboard%20Engine/2001/BF90A1%20LRTA%20MARINE%20ENGINE%2C%20JPN%2C%20VIN%23%20BBBL-4400001%20TO%20BBBL-4409999/CARBURETOR/parts.html

There are also transition ports (little pin size holes) inside the top of the carburator. Make sure all those are clear. These holes are for idling and slow and intermediate speeds. You may have to take very small wires to poke through the debris that may be in them.

Make sure you use new o rings and gaskets. Also, be sure that you cleaned the intake manifold and replace that gasket too so it does not suck air or let water into the cylinders.

Lastly, the carbs should all be vacuum balanced so that they all essentially suck the same and work efficiently together. If you put the carbs back onto their original positions and did not play with the adjusting screws, you may be pretty close. If you mixed them up, they are probably out of sync. If the balance is out, the idle will not be smooth and acceleration may be quirky.

Those were just some of the highlights. Float height, good fuel (no water), and good spark plugs (use NGK DR7EA not a substitute) all help the runability.

Mike
 
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