Bad Boy not getting gas

Bad Boy Fan

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My 2016 Bad Boy ZT has been so very good, but would not start. Turns over and will start with starting fluid, but not continue to run. I replaced the fuel filter and although the fuel filter is about 3/4 full of gas it still will not start. I replaced the "fuel pump" and still will not start. I cannot understand how the "fuel pump" actually pumps gas. The fuel is always non-ethanol. Suggestions please.
 

Richie F

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" I cannot understand how the "fuel pump" actually pumps gas."
The pump is activated by the engine crankcase pressure.
As the engine rotates there is a pulse made.
This pulse pumps the fuel pump, which intern moves the gas from inlet to outlet of the fuel pump.

Sometimes a new pump is dry.
Try putting some gas into the outlet side hose of the new pump to help wet the valves inside it and see what happens.
Leave the outlet hose off the carb to watch for a pumping action as you crank.

Also make sure the crankcase pulse line is in good shape, no cracks, ect.
 
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Scrubcadet10

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like richie said to check if the pump is working, pull the hose off the carburetor and try to start, if it spurts out gas, pump is working.
then i would suspect a carb cleaning is needed. it can be as simple as a small piece of fuel line that comes apart to clog things up.
 

bertsmobile1

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pull the fuel line off the carb & crank the engine
If fuel spurts out the end of the fuel line, pump is fine .
Remove the solenoid from the float bowl.
Check that the plunger snaps back very quickly when the power is turned on .
Check that the rubber cap ( if fitted ) is on the end of the plunger.
It is really hard to help you when we have no idea about which engine you have in there
If it is a fuel injected one I have just wasted my time
 

Richie F

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Remove the solenoid from the float bowl.
Check that the plunger snaps back very quickly when the power is turned on .
Check that the rubber cap ( if fitted ) is on the end of the plunger.
It is really hard to help you when we have no idea about which engine you have in there
If it is a fuel injected one I have just wasted my time

If the engine does have a solenoid, that's a good point.
Don't know what you mean by "rubber cap is on the end of the plunger" ?

"If it is a fuel injected one I have just wasted my time"
No you haven't. You did give valuable info into this problem.

If it is injected, the pulse pump is a transfer pump, feeding the electric pump that develops higher pressure to the injector(s).
 

Scrubcadet10

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If the engine does have a solenoid, that's a good point.
Don't know what you mean by "rubber cap is on the end of the plunger" ?
The plunger is made up of a small steel rod and what stops the fuel is the rubber plunger on the end of that rod.
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Bad Boy Fan

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OK, resolved! I had a friend come help me. It took us a couple hours for him to discover that it was my error! I had not noticed a cap on the end of the fuel pump that make the pump do it's job of pumping. The cap blocked the pull/push necessary to pump the gas. I could write a book about the inability to outgrow stupid. I just try to learn from each stupid thing I do and not repeat it. So far, pretty good.
 

Bad Boy Fan

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" I cannot understand how the "fuel pump" actually pumps gas."
The pump is activated by the engine crankcase pressure.
As the engine rotates there is a pulse made.
This pulse pumps the fuel pump, which intern moves the gas from inlet to outlet of the fuel pump.

Sometimes a new pump is dry.
Try putting some gas into the outlet side hose of the new pump to help wet the valves inside it and see what happens.
Leave the outlet hose off the carb to watch for a pumping action as you crank.

Also make sure the crankcase pulse line is in good shape, no cracks, ect.
Thanks, Richie! That is what I learned from my friend that showed up to help me. I had taken the old fuel pump apart and saw the springs and diaphragms but did not put the dots together that the crankcase pressure was the driving force for pumping until he told me. I learns something daily, but forget so much more at my age.
like richie said to check if the pump is working, pull the hose off the carburetor and try to start, if it spurts out gas, pump is working.
then i would suspect a carb cleaning is needed. it can be as simple as a small piece of fuel line that comes apart to clog things up.
pull the fuel line off the carb & crank the engine
If fuel spurts out the end of the fuel line, pump is fine .
Remove the solenoid from the float bowl.
Check that the plunger snaps back very quickly when the power is turned on .
Check that the rubber cap ( if fitted ) is on the end of the plunger.
It is really hard to help you when we have no idea about which engine you have in there
If it is a fuel injected one I have just wasted my time
Thank you for replying. Yeah, we pulled the hose off the pump destined to the carburetor and determined the pump was not pumping. That led to checking the crankcase and final resolution.
 

Richie F

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Thanks, Richie! That is what I learned from my friend that showed up to help me. I had taken the old fuel pump apart and saw the springs and diaphragms but did not put the dots together that the crankcase pressure was the driving force for pumping until he told me. I learns something daily, but forget so much more at my age.
Thank you for replying. Yeah, we pulled the hose off the pump destined to the carburetor and determined the pump was not pumping. That led to checking the crankcase and final resolution.

And so ?
With all your poetic talk did you replace the pump and solve the problem ?
" I learns something daily, but forget so much more at my age."
Sorry, sounds like you might be like 90.
 
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