carbs are driving my insaine

[dhethridge]

I have a 2000 Yamaha f40 tlry on a 2000 playbouy pontoon 16 ft. the previous owner let the boat sit in the water for 3 years with out doing a lick of maintenance on it. when I bought it. I replaced the water pump, new ngk plugs oil changer with new filter. the bottom carb is great. however the middle and upper carb the high side is still stopped up. it will idle and run great on a water hose and muffs. but when I have the boat under a load in the water I can not get more than 7mph out of it. I have found the blockages in both middle and top carb. it is in the bowls. then have been sitting in a gallon can of carb cleaner for a week and this blockage has not moved. please can anyone tell me how to get them clear. I can not afford right now to take it to the dealer so I am stuck my self and a buddy of mine. we are both ase certified auto mechanics. I thought this would be easy but I guess I am wrong. thanks yall. please any help will be great.


dax

[robert graham]

Some folks recommend ultrasonic carb cleaning....Harbor Freight sells a few units pretty cheap....something to consider here....

[boscoe99]

How do you know for sure that the problem is within the bowls?

Have you disassembled the bowls to the extent that you can do so?

Are you using a heated ultrasonic cleaner to clean them?

Have you tried using compressed air to blow out any debris within the bowl passages?

Have you tried to rod out the bowls using a soft copper wire?

If the bowls are corroded internally then there might not be a fix. Might be time for new $140 bowls. Ouch.

[dhethridge]

I am looking into the ultrasonic cleaning now. new carbs for the thing a 632 a piece that's the ouch.thanks for the idea about the ultrasonic machanie I am on harbor freight now looking for one. Robert.

[boscoe99]

The upper part of the carburetor more times than not can be successfully cleaned. There is a modification that can be done to facilitate the cleaning process. The accelerator pump nozzle can be drilled out with a #80 bit if it gets clogged.

The bowl is usually the bigger problem. Water can get to internal parts of it and cause corrosion that is all but impossible to remove.

[dhethridge]

I think that is the problem all the jets and passages on the upper carbs has been rebuilt. but I am still having the same problem. my buddy and I looked at it yesterday. it is definitely in the bowls. I think I am going to go ahead and order new bowls. like I said the motor and pontoon set in the water for 3 years with fuel in the carbs and no type of maintenance completed..

[TownsendsFJR1300]

The jets you have clogged are screwd into the carb body itself. There should be an idle jet and high speed jet.

You can usually just pull the bowl, pull both jets (each carb) and LOOK THRU THEM. If you cannot see light or blow thru them, their clogged.

They make small wire "jet cleaners" for about $10.00 but a sewing needle and soaking the jets in lacquer thinner will help release the varnish.

Soaking the bowl itself (I use a small steel tuna fish can). If the jet opening is REALLY SMALL, a piece of wire cut off a hand held wire brush, clamped in a small vise grip works well.

Once you get it running, put some Yamaha "Ringfree" in the fuel, it'll help clean out the rest of the system. A fuel stabilizer is a MUST UNLESS YOU DRAIN THE BOWLS AFTER EACH USE.. They will clog up again...

Your carbs:
http://www.boats.net/parts/search/Ya...TOR/parts.html