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My 3184 has always been hard to start after sitting for awhile (week). Problem was not pumping gas to the carb. So I would prime it and mow until the next time, maybe it would start maybe not.

Then it started burning oil (250 hrs.). While putting on new head gaskets I noticed the little tab on the fuel pump in the valve cover was broken off, I thought there's my problem I have been dealing with all these years.

Ordered a new valve cover/fuel pump (after market) assembled everything started right up not burning oil anymore, thought I was golden.

Went to mow next time same problem. To get the fuel to pump I have to mist gas into the carb. while turning to key until the filter fulls up and starts to pump gas. Then while mowing it will shut off for no reason and I will have to do it again.

When it's running it runs good so the fuel pump is working at that point, it's like I just loose prime.
I have changed fuel filters a number of times, checked the lines but haven't changed all of them, blew air through the lines into the tank, had the new pump off a couple times, everything looks fine. I was thinking has to be the new pump but it done almost the same thing with to old broken tab pump. Any ideas?
 

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I'd change the fuel lines tank to carb and look for kinks in it. Make sure they are routed away from anything hot as the dying after running could be a vapor lock issue.

Make sure you dont have packed grass around the hydro as the fuel line is next to it.

I changed mine easily on my 3240 by pulling the seat track bolts and lifting the seat /toolbox assy off. Go from there.
 

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"Then while mowing it will shut off for no reason and I will have to do it again. "

This might indicate a problem with the solenoid on the bottom of the carb,or the wiring to it, not sure about the starting affect being related to this but I would check it.

Walt Conner
 

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if your pump doesnt pump efficiently enough to start... and then the mower cuts out while mowing - sounds like you still have a fuel flow problem.
did you change the fuel filter recently?... did you try removing fuel line between carb and pump to see how rapidly the pump is pumping?.. both with fuel and when cold/dry..... the pump should pump fuel very efficiently - even when not primed - because i'm quite sure it's a diaphragm type - which means it can pump air or liquid with the exact same efficiency.... thus self priming easily.
It is possible you have blockage inside the fuel tank - there normally is a pre-screen there. It is also possible you have a pinhole air leak somewhere in your fuel line inside the tank, such that once it's wet with fuel it improves the seal, but when dry - air sneaks in (had this exact thing happen on a boat fuel tank once).
lastly, take your fuel pump apart - maybe there is a piece of dirt stuck in the diaphragm or check-valve (little rubber flap), preventing a good seal against air.

if all that fails, get an electric fuel pump for carb's which makes 4-6psi (unlike many fuel injection pumps that can make up to 60psi), hook it up and never look back.
 

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Discussion Starter #7
if your pump doesnt pump efficiently enough to start... and then the mower cuts out while mowing - sounds like you still have a fuel flow problem.
did you change the fuel filter recently?... did you try removing fuel line between carb and pump to see how rapidly the pump is pumping?.. both with fuel and when cold/dry..... the pump should pump fuel very efficiently - even when not primed - because i'm quite sure it's a diaphragm type - which means it can pump air or liquid with the exact same efficiency.... thus self priming easily.
It is possible you have blockage inside the fuel tank - there normally is a pre-screen there. It is also possible you have a pinhole air leak somewhere in your fuel line inside the tank, such that once it's wet with fuel it improves the seal, but when dry - air sneaks in (had this exact thing happen on a boat fuel tank once).
lastly, take your fuel pump apart - maybe there is a piece of dirt stuck in the diaphragm or check-valve (little rubber flap), preventing a good seal against air.

if all that fails, get an electric fuel pump for carb's which makes 4-6psi (unlike many fuel injection pumps that can make up to 60psi), hook it up and never look back.
Thanks for the advice, I have yet to pull fuel line out of tank.
 

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Discussion Starter #8
Haven't had time to look into my problem but got it started today to mow and it lasts about 45 minutes before it stops pumping gas into the carb.
 

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It seems when it starts, it runs well with no problems.

I'd start with the fuel tank. It may be dirty and needs dropped to wash out. If it has a screen at bottom of tank before going into fuel line, it may be caked over enough to dribble enough fuel to fill the line to pump, but not enough to sustain for long periods of needing that fuel.

Now look to see if gas cap vent hole(if has one) is clear. You may need to use compressed air to blast out any dirt/grim that's blocking underside of hole that can't be seen. If plugged, it's causing a vacuum on fuel tank to not allow gas to flow correctly into fuel line.

If you're in a real hot area of country, you could also be getting a vapor lock in fuel line, but you normally only see this if engine is off after a long running and it sits for a bit, but you never know with today's fuel. With this cheap ethanol gas, and maybe using a too low of octane, it could be burning off before it's getting to carb, so you wind up with not enough fuel getting into carb. You may need to wrap something around the fuel line to help draw off the heat the engine might be generating. A split rubber fuel line that's one size larger than the line it's going over, that's zip tied around it to hold in place can help. It can be anything to help insulate and draw off heat to keep the gas cooler if line is running along side the engine..

Something, I noticed this year when I changed out my fuel filter over the winter to prepare for spring on my commercial mower that uses an ONAN P220, was when I installed the filter it was a different type than I normally used, and it was cheap and more compact. I went with styling and price over usage. I had also run new fuel line from tank to carb, after also removing and washing out gas tank of any crud from 29yrs.
This new filter was rated to filter out debris at 20-25 microns if I remember. My machine ran like crap. Kept surging and seemed down on power. Removed the carb's top to look at interior and jets to see if something blocking any ports. Nothing. After doing this 2-times with carb thinking something was blocking a jet somewhere in carb and finding nothing, even after blowing out all ports, I decided to switch out fuel filter, back to the original type I had on. IT WORKED. Come to find out the older filter is a 70 micron filter and allowed the proper flow of fuel to carb.

The cheap/compact inline fuel filter I replaced in winter was a small screen type. The original(larger) fuel filter I went back to is more of an automotive opaque(semi-clear) using a paper element inline filter.

Look at your fuel filter to be sure it's correct style/type that your engine won't be choked down with fuel flow. Most filters I found will say on the back what microns it will filter out.

Del
 

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Discussion Starter #10
Turns out that cheap fuel pump/ valve cover was not working right. I hooked up a B&S vacuum fuel pump I found at work and it is working fine (for now) thanks all for the advice. This was after I have checked all my fuel lines and line into the tank.
 

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Something else to always consider when working with fuel systems is the vent in the fuel tank cover. I had a couple of plugged ones and if your not thinking about it, it's easy to miss. A plugged vent also makes the fuel pump work harder and may cause early failure.

Bill
 
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