So I’m try to figure out this fuel problem. The pump isn’t putting out what it should be. I’ve tried pulling from a cup with no filter and maybe get 3 ounces. So I thought I’d clear the lines drain the tank and have a look. The last ride out it was fine till about half tank. What is the mesh thing all about and which line is what inside. Reserve and main.

You can fix it. Its like building a ship in a bottle.

I'm thinking the line with the mess has to be main and the other is the the reserve.

I wonder if the mess has to do with splashing ????

Wish I knew more.

Hey fully -- If you got a flow problem try doing what I have to do on my machines once a year. Because my pickup lines were badly corroded, I now pull fuel from the drain plug. This means that sometimes that little hole in the plug gets slightly plugged with poo. So once a year I hook an air hose to the fuel line and blow back into the tank at full pressure. I have had no issues with fuel flow. Leave the cap on tank open but laying on the hole or fuel will spray out. Ask me how I know.
Also noticed in that pic that the strainer has come off the tube. It might have poo in it now.
CO

The strainer as you call it is the mesh yellow thing. It’s all torn up at the bottom as well no idea what it’s for.

So the shop in town did have the big mikuni pump DF62-702 supposed to put out 65L/hr. With filter on pulling out of a pail I’m only 3.5ish. Without filter I’m just at 4.5. ((Bad Word)) it. I’ll run it the way it is and watch egt.

Well that tells me that maybe the filter is plugged a bit or it's to far from the pump.
Pumps don't pull fuel very well. Pumps pump. It's possible your vacuum line may not be tight ??. Not sure. If it puts out 4.5 with no restrictions then the pump is good the way I see it.
CO

Edit: Are you using both outlets ?? I "T" both the outlets on my brothers machine and then to carb.
CO

Edit again: The strainer keeps poo out of the fuel lines. Without a strainer you just pull what ever out of the tank.
CO

Yes I bought a Y fitting. Pump is in stock location fuel filter is also in stock location so I don’t know

I would like to know how those lines work inside of the tank which one does what what is the purpose of the mesh it connects at the top and at the bottom so what’s the purpose of it

The mesh keeps big poo out of the lines.
The two lines in the tank each have a strainer.
The short strainer is the reserve line.
The tall strainer is the main.
CO

But looking at this pic. The tubes are connected by the mesh

I was just looking at my computer for pictures of my old fuel tank pick up tubes.
Sorry I can't find them. Maybe deleted. But based on what your pictures show there, you have two tubes correct ?? Each one should have their own screen.
I can't remember now it's been so long.
CO

Edit: YES they may use the same screen.
Bottom tube is reserve.
Top tube is main.
They are connected as you say.
CO

Edit again: Take a close look at your last picture. You can visualize it.
CO

Here is a pic to help.
As you can see in the pic -- at this point you are running the reserve. The main is above the fuel level.
If you were on the main you would be sucking air.
CO

Ok so hard to tell. But I’m guessing around the 5” mark is when you need to switch to reserve. Does reserve flow the same rate as main

YES.
CO

Weather or not you run the screen doesn't really matter.
The screen just prevents a big piece of rust from going into the tube and plugging it up.
CO

That’s kinda what I thought. My tank is pretty clean so I’m not going to swear over it now.

Yeah I think you are stressing over nothing. It's a non issue right now.
CO

Are you using a stock filter?
If not what is the micron on the filter?
Is the filter before the pump?
You have to be careful not to restrictive before the pump. A high number before and low number after.
If stock filter not a factor.
I always run my tank valve in the reserve position. fuel light come on head back and fuel up.

CO, av gas on drawing. Priceless

I did read you tested with no filter.

YES -- good one adnoh. I didn't think about that.
CO

Adnoh it’s the last stock filter I had. It’s two years old now. So I flushed it about 20 times today till the fuel was clear coming out. I can’t find them anymore

The petcock is before both the filter and the pump. I bet its cruded up.

The best I ever got was 5oz/10s of a fresh clean setup pulling from tank drain with polaris pump.

Ooooooooohh another piece of great advice if a guy has fuel issues.
I didn't even give that piece of the system any thought. Good one.
I wonder if there is any strainer material stuck in there ??
CO

I can just get get 4.5 pulling it from a cup full with no filter. There’s nothing in the petcock

Most of us have been doing this fuel flow test using the starter.
The standard has always been 4.5 oz in 10 sec.
The Honda Pilot manual says 4.7 oz in 10 sec at idle.
I don't know if anyone does it that way. It's a big fire hazard in my opinion but that's what the Pilot manual says. There is no mention of this test in the FL350 manual, or at least I have not read it in there.
These are pulse pumps. Obviously the more pulses the more fuel --- No ??
Also pumps are weak when trying to "pull" fuel. Most industrial pumps I have worked on are flooded suction. These little pulse pumps have to pull a bit of head but not much so I don't think that is an issue here. The biggest issues would be corroded pick up tubes, loose vaccum line, plugged filter or to restrictive filter, air leak in the crank case, shtyee pump.
None of these issues seem to be the problem here. Everything passes.
I know the starter spins a FL350 Engine about 450 rpm. The idle is a lot higher than that.
One of these days I have to do a flow test using the starter and then the idle method and video tape it. Looks like I got another project for the winter.
CO

Yeah there’s a few factors that can affect the outcome. I know I’m getting more fuel now. Had to take the jet out of the return line as it was pushing past needle and come out the over flows