Bad Breather

PTmowerMech

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I rebuilt the carb and there was no jet. I properly installed a new one with new o-ring. It runs great for about 15 mins. I'm gonna pull the carb off and check it again.

Is the fuel solenoid ok?
 

Freddie21

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Yes, but I don't know how that would cause it to run rich.
 

StarTech

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With it being a Nikki the bowl gasket might have a bad place in it. They have to be nearly prefect, Otherwords, no nicks.. Also verify you installed the correct jet size.
 

Freddie21

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Will have to check the jet. I don't know which one I put in. But, again, if the jet is wrong, I would think it would run crappy all the time not just when it gets hot. I wondering how the carb would fail with temperature. Unless, the mixture is good only when cool.
 

Freddie21

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I disassembled the carb and everything is correct, but it surging even at low speeds now. I rebuilt another Nikki using used parts and it runs well. Let it run at high speed for 15 mins and still good. I agree, I hate these carbs. I tried to convert a Walbro, but the throttle brackets are different. I couldn't swap as throats are different sizes. I've seen this done on UselessTube.
 

Freddie21

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I was wondering if the breather needed vacuum to operate and if the engine would not run correctly if the tube was not connected, but I have been running this engine with a rebuilt carb and no breather tube connected and it runs fine. The tube is cracked at the air cleaner elbow. Should I fix?
 

Tiger Small Engine

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I was wondering if the breather needed vacuum to operate and if the engine would not run correctly if the tube was not connected, but I have been running this engine with a rebuilt carb and no breather tube connected and it runs fine. The tube is cracked at the air cleaner elbow. Should I fix?
Buy a cheap Chinese carburetor and throw it on there. Use a spark checker to check coil(s). After 15 minutes when it starts running crappy, besides the smoke, does it hunt and surge? Spit and backfire, etc?
 

bertsmobile1

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The main jet sits in the bottom of the white tube and is held there by the o-ring
Without it the engine will run fine until the governor allows the throttle butterfly to open fully when it will run very rich
There are 2 different types of gaskets for them
The Chinese repair kits do not fit , they are made for the Chinese clones that are smaller overall
I fail to understand why people have so much difficulty with them
The only problem for me is those bowl bolts that I am now replaceing with Allan headed cap screws so I can remove the bowl without having to remove the carb
 
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