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I have a Wright Sentar with a Kawasaki 25HP FH921V-BS07 with a Nikki that is labeled 150037048 266401 - although the Kawasaki documentation states that I should have a Nikki P/N 621266. I have not been able to find any documentation on the Nikki carbs. I also suspect that the shut-off solenoid is not working. Can it be bench tested?

In any case, the engine has always been had to start - from day 1. It had gotten so bad that I had to pour gas into the carb to get it to start when cold.

Recently I had the cover off the engine exposing the fan to check the resistance of the coils while hot. One thing lead to another and the fan broke and I overheated the engine. This created a crack on the block behind the starter and a huge backfire was heard when it shut down. Backfiring is nothing new - it always backfired when I shut down.

With the crack in the block, oil smoke billowed from the engine and oil was spraying everywhere when I stopped. While on the way back to the garage after the fan broke, the throttle had little to no effect on the speed of the engine - seemed odd at the time, but I assumed the cable was slipping what with all the oil that was spraying around, or that something had come un done.

In the process of repairing the block (with JB Weld - it worked great, so far), I decided it was time to disassemble the carb for cleaning to correct the hard starting.

All is now well. It starts almost immediately, but I still don't have any throttle control. I have confirmed that the choke and throttle butterflies are operating as they should, but I still get no change in engine speed with throttle movement. I'm at my whit's end, PLEASE CAN ANYONE HELP.

Wow!

So while running, if you manually move the throttle lever on top of the carb open and closed, does it speed up and slow down?

I really can't access the carb itself due to the way the motor is mounted, but moving the throttle lever (and therefore moving the carb linkage), has no effect on engine speed.
Wow is right - I'm confused. I'm wondering if the violent backfire(s) have damaged something in the carb?

belair gregg said:

I really can't access the carb itself due to the way the motor is mounted, but moving the throttle lever (and therefore moving the carb linkage), has no effect on engine speed.
Wow is right - I'm confused. I'm wondering if the violent backfire(s) have damaged something in the carb?

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I don't want a new carb - isn't there someone out there that can help?? Why can't I find documentation for the Niiki Carbs on line - there is nothing available. Is it National Security info ??

belair gregg said:

I don't want a new carb - isn't there someone out there that can help?? Why can't I find documentation for the Niiki Carbs on line - there is nothing available. Is it National Security info ??

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https://www.nikkinet.co.jp/english/ How much more information do you need ? If you read my posts above, I believe all the information you need is included. By the way, how old is your piece of equipment & number of hours used?

Kawasaki Part Number: 15003-7048

belair gregg said:

but I still don't have any throttle control. I have confirmed that the choke and throttle butterflies are operating as they should, but I still get no change in engine speed with throttle movement. I'm at my whit's end, PLEASE CAN ANYONE HELP.

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Well how is this then? Which is it? How then could you "confirm" that the choke and throttle butterflies are operating as they should? We would like to help, but the questions should at least make a little sense.....

Fish said:

Well how is this then? Which is it? How then could you "confirm" that the choke and throttle butterflies are operating as they should? We would like to help, but the questions should at least make a little sense.....

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I can see the choke butterfly and confirmed that it moves with the panel mounted chock knob. If you are familiar with this carb, the throttle butterfly is not visible unless the air cleaner mount casting is removed. I loosened the carb to intake mounting bolts and nuts, but did not remove the carb or disconnect the linkage. By pulling the carb slightly off the intake, the throttle butterfly is exposed. I was then able to see the butterfly move when the throttle was moved.

I'm still amazed that I cannot find any Nikki carb documentation on line!!!!!!!!!!!!

mechanic mark said:

https://www.nikkinet.co.jp/english/ How much more information do you need ? If you read my posts above, I believe all the information you need is included. By the way, how old is your piece of equipment & number of hours used?

Kawasaki Part Number: 15003-7048

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The mower was purchased in the spring of 2004 and has 485 hrs.

mechanic mark said:

https://www.nikkinet.co.jp/english/ How much more information do you need ? If you read my posts above, I believe all the information you need is included. By the way, how old is your piece of equipment & number of hours used?

Kawasaki Part Number: 15003-7048

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I have the exploded view - I have the Kawasaki manual, in print and electronic form - what I don't have are instructions for initial settings for the pilot jets and how to disassemble the float. Any details would be nice - I took it apart, so I know how it goes back together - the exploded view is of little value.

Fish said:

Well how is this then? Which is it? How then could you "confirm" that the choke and throttle butterflies are operating as they should? We would like to help, but the questions should at least make a little sense.....

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I wonder if the throttle butterfly would be restricted if I had over torqued the carb mounting studs and nuts? I can only verify the butterfly action when the bolts and nuts are loose. I'm not feeling any resistance in the throttle cable however.

Hold up I think the bigger issue is the crack in the block... And Jb weld is not a permanent solution and could lead to bigger problems.

exotion said:

Hold up I think the bigger issue is the crack in the block... And Jb weld is not a permanent solution and could lead to bigger problems.

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Please elaborate. The epoxy is holding for now and I don't have the cash for a new motor. If I can't get the carb situation resolved it's a moot point anyway.

belair gregg said:

Please elaborate. The epoxy is holding for now and I don't have the cash for a new motor. If I can't get the carb situation resolved it's a moot point anyway.

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You don't need a new engine. It can be welded. Now as far as the carburetor go's I will stay out of that being I don't under stand why the engine speed can't be controlled if the throttle butterfly is working OK. Maybe a vacuum leak?? It has to be getting fuel and air from some place? It looks like repair shop time to me!!!

belair gregg said:

Please elaborate. The epoxy is holding for now and I don't have the cash for a new motor. If I can't get the carb situation resolved it's a moot point anyway.

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I think a proper weld needs to be in place the Jb weld will not hold for very long its a good temporary fix however. Guess it'll work until you get the other issues worked out. I would follow the fuel start at the tank make sure the tube isn't blocked next is fuel lines and filter then the fuel pump if equipped. Then check carb is getting fuel spin the engine a few times see if the carb is delivering fuel. If not delivering fuel problem is in carb if it is the problem lies elsewhere