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I have a FX1000v that is not drawing fuel to or through the fuel pump. The vacuum line does not appear to have any suction. What or how does this work?

This engine has two fuel pumps. A diaphragm pump, which creates the fuel lift and flow. This acts as a helper to the electric fuel pump. The electric pump does not have enough suction power to pull from the tank itself. But, it does provided the necessary fuel pressure to the throttle body.
So, first you want to establish if you are getting flow from the diaphragm pump.

txmowman said:

This engine has two fuel pumps. A diaphragm pump, which creates the fuel lift and flow. This acts as a helper to the electric fuel pump. The electric pump does not have enough suction power to pull from the tank itself. But, it does provided the necessary fuel pressure to the throttle body.
So, first you want to establish if you are getting flow from the diaphragm pump.

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???

The FXT00V-BS21 (FX1000V-BS21) that I just recently repaired only had the vacuum operated fuel pump. It was on a Hustler Super Z ZTR.

Need the equipment info on both the mower and the engine spec number As we need to know if this engine is the carbureted or fuel injection setup. Just can't assume it is one or the other.

The BS21 is carbureted. I guess I jumped the gun assuming that this question was DFI related as a carbueted pulse pump would be rather easy to diagnose. My apologies, Tim.
If this is a carbureted engine, the diaphragm works from positive and negative crankcase pressure created by piston movement. If the pistons are moving, it is either, and most commonly a failed pump. Or, if there is an issue with the pulse line from the cylinder head to the fuel pump. Or a possible issue with the breather reed valve.

txmowman said:

This engine has two fuel pumps. A diaphragm pump, which creates the fuel lift and flow. This acts as a helper to the electric fuel pump. The electric pump does not have enough suction power to pull from the tank itself. But, it does provided the necessary fuel pressure to the throttle body.
So, first you want to establish if you are getting flow from the diaphragm pump.

Click to expand...

Hello,

This is a carbureted engine. It is on a Dixie Chopper Xcalibur 3572. This is a new fuel pump, new fuel shut off solenoid at the carb, and some new lines. I have not replaced the vacuum line from the motor to the pump and I can not tell you if the engine runs, as it has not since the customer ran it out of fuel and brought it to us. We obviously thought this was an easy fix and it has turned in to all of this that we are new to understand.

This is a carbureted engine. It is on a Dixie Chopper Xcalibur 3572. This is a new fuel pump, new fuel shut off solenoid at the carb, and some new lines. I have not replaced the vacuum line from the motor to the pump and I can not tell you if the engine runs, as it has not since the customer ran it out of fuel and brought it to us. We obviously thought this was an easy fix and it has turned in to all of this that we are new to understand.

Double check the fuel line connections. It is easy to connect them up wrong if you are new to these vacuum pumps.

Their does not appear to be any vacuum coming off the motor when we crank it.

It doesn't take a lot to work the pump. Probably only around 1 psi.

Hold a piece of tissue paper over the end of the vacuum line from the engine
If the pistons are moving then the vacuum line will be blowing and sucking unless there is a big hole in the line or a bigger one in the crank case
If it has been off overnight check for creepy crawlies which for some reason seem to like to crawl in and die .