2014 4.3 liter TKS bogs after running 35 knots for 45 minutes.

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Bondo

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Diagnosis is done in steps,..... step #1 has been stated,.....

As for the anti-siphon valve,.... they can usually be cleaned out, 'n reused,....
 

coolbucket

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I think I'll pump out the tank, run an auxiliary tank test and take it from there.
 

Scott Danforth

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If that happened, what to do about it? I find it awful puzzling that I ran strong as a rabbit for over an hour and then stopped and idled around and then took off again and it ran like crazy that there would be stuff in the carburetor again.
You clean the carb again

Idle circuit is first to get plugged along with accelerator pump circuit as they are the lowest in the bowl

High speed circuits s are higher in the bowl
 

coolbucket

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Clean it with what? I'm going to drain the tank and put a new Fuel,water filter on it too.
 

nola mike

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What's everybody thinks of this?
As simple as this sounds you always start by running it off of a different fuel tank, like a small plastic portable tank. Half the time there isn't anything wrong the motor itself, but rather something wrong with the boats fuel system. This can be a pinched or collapsing fuel line, bad or old gas, or a bad anti siphon valve. Marine engines are very sensitive as to the quality of the fuel, and if any part of it is over 90 days, the fuel itself is always going to be suspect. This is a pass or fail test, and the engine is either going to run better or it is not. If it does run better, on this portable tank, first change the anti siphon valve and retest with the engine hooked back up to the boats fuel tank. If it goes back to running poor on the boats fuel tank, that tank will need to be pumped out. Bad anti siphon valves are a common problem, when they go back they create a blockage and restrict the amount of fuel that flows to the engine
Running it off of a separate tank can help diagnose, but there are many things that can cause it to run better off of a remote can
 

coolbucket

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As in, disassemble, clean, and rebuild carb. Not spray stuff into throat of carb.
I just had it rebuilt last week. I'm going to drain the tank, new Filter, then try again. If it still faulters at idle I'll rebuild again.
 

coolbucket

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I just had it rebuilt last week. I'm going to drain the tank, new Filter, then try again. If it still faulters at idle I'll rebuild again.
I'm also going to change out the Anti- syphon valve, maybe the coil. Eventually I'll find the problem.
 

Scott06

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I'm also going to change out the Anti- syphon valve, maybe the coil. Eventually I'll find the problem.
Take a few minutes and read what diagnosing direction Bondo is sending you in before you get out the parts cannon....

Since coils rarely fail - you can easily check with an ohm meter.
 

Scott Danforth

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I wish I had $1 for every coil replaced that was not bad. I would be a billionaire and living on my own island.
 

coolbucket

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I ran hard for 30 minutes straight on intercoastal, stopped for about two hours. Ran back about 35 mph for 30 minutes. Sometimes throttling down for wakes. Idled through channel for 10 minutes. Went to accelerate she bogged and popped. Got her to run at 25 mph, tried to gun it, she popped and bogged. Just rebuilt carb and new fuel/ water separator. WTFrick?????
 

Scott06

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Go back through carb. would be looking at accelerator pump discharge and float level sounds like when u nail it it is not getting fuel
 

coolbucket

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Happened again yesterday. Ran it hard for 30 minutes, ran great. Stopped for a few hours ,ran it hard for another 30 minutes. Idled, 5 mph for about 10 minutes, gunned it, it bogged and popped. Got it to go 25 mph. Tried gunning it and it popped and bogged.
 

Scott Danforth

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popping is running lean.

its called a lean sneeze.

did you remove the carburetor and go thru it? sounds like the accelerator pump circuit is clogged.
 

coolbucket

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popping is running lean.

its called a lean sneeze.

did you remove the carburetor and go thru it? sounds like the accelerator pump circuit is clogged.
I through the TKS carb in the garbage. Put an electric carb on there and she runs great.
 
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