Fuel blockage or bad pump or other?

mikeinri · Aug 8, 2018

What's the best way to diagnose the source of this problem?

I have a 2003 Husqvarna GTH2548 (repowered with a much newer Briggs, see my signature), which stalled on me the other day. It's acting like it's starving for gas (ran better with choke for a short while). I could get it running roughly, and it would stall if I tried to engage the mower deck.

I noticed that the fuel filter (clear) had very little fuel in it, and when I restarted it, it seemed to disappear. I had been cutting grass for about 30 minutes prior to this, with no warning symptoms. I was able to drive it back to the shed, but running roughly the whole way.

I had just refilled the tank earlier in the day, not sure if I may have dislodged something in the tank, or if that was just a coincidence???

This tractor is new to me earlier this year.

Mike

dave_r · Aug 8, 2018

I would suggest disconnecting the fuel hose leading into the fuel filter from the tank and seeing how gas runs from it. Given that the filter housing gets pretty empty, I think you'll find it doesn't flow very well.

If so, it could be the hose itself or the tank outlet that is plugged.

Whirly · Aug 8, 2018

mikeinri said:
What's the best way to diagnose the source of this problem?

I have a 2003 Husqvarna GTH2548 (repowered with a much newer Briggs, see my signature), which stalled on me the other day. It's acting like it's starving for gas (ran better with choke for a short while). I could get it running roughly, and it would stall if I tried to engage the mower deck.

I noticed that the fuel filter (clear) had very little fuel in it, and when I restarted it, it seemed to disappear. I had been cutting grass for about 30 minutes prior to this, with no warning symptoms. I was able to drive it back to the shed, but running roughly the whole way.

I had just refilled the tank earlier in the day, not sure if I may have dislodged something in the tank, or if that was just a coincidence???

This tractor is new to me earlier this year.

Mike

first off.. is the filter located on the tank side of the pump.. if not a lil part of trash could take out the pump.. the other thing is to clean the carb..

iRodent · Aug 8, 2018

I just got done dealing with something similar with my GTH2548, except mine was repowered with a Kohler Courage 25 (SV730). It'd run great all winter, but now that it's hotter, it'd run until the engine was good and warm and act like it was starving for fuel. I replaced the pulse fuel pump with another, same thing. Then one day the dipstick blew out and I realized my case pressure was wonky. There was a breather hose on the top of the engine that ran from the case to the intake that would pinch off when it was hot. Replaced that, and now my engine has normal case vacuum (actually pulls the dipstick down now) and the pulse style fuel pump keeps the fuel filter full now.

Just another avenue to check. I spent months trying to diagnose it, throwing parts at it, replacing fuel lines, fuel pump, filters, everything, then found it was a soft vent hose causing the issue. Another thing I read during that time is the hose from the fuel pump into the carb can get weak and kink off when they get hot, causing the same issues.

[edit]
One of the symptoms for my particular issue was oil seeping out of the pulse fuel pumps metal mesh. A quick way to check your crank case pressure (at least with my style of engine), is to pull out the oil dipstick and hold it just slightly out of the holder to feel for the crank pulses. If it pulls the dipstick back down into the holder your good. If it blows oil everywhere and makes a huge mess, you got a crank pressure issue and the pulse style fuel pump won't work properly.

mikeinri · Aug 9, 2018

Thanks guys. Yes, the filter is between the tank and pump. The engine is new old stock (supposedly installed within the past year). Not sure if the pump was replaced, but I suspect the fuel line (at least from the tank to the filter) wasn't.

I bought a new piece of fuel line, I'll probably just swap out proactively and test for flow.

Mike

cms1528 · Aug 9, 2018

First remove the fuel line leading into the filter. I bet no gas will come out of the fuel line or it will stop flowing within a few seconds. With the fuel cap on the tank firmly blow into the fuel line like your blowing up a balloon for about 5 to 8 seconds. You might even hear it make a bubbling sound inside the tank. Then stop and if fuel starts flowing connect the fuel line back onto filter. Fire up the mower and operate it for awhile and see how it runs.

If it works you likely just have dirt or settlement of some sort at the bottom of your fuel tank. Blowing into the fuel causes the settlement to circuit around in the fuel thus allowing the fuel to pass freely through the tank and fuel line. Another possibility is a blocked fuel tank breather hose if you have one or maybe a fuel tank breather outlet of some other sort if one is present. If not simply run the gas out and flush the tank with some kerosene or specific tank cleaner to remove the dirt or settlement. Your tractor is a number of years hold and over time dirt can make it's way into a fuel tank when you open it to put gas in.

I've experienced this problem my self and I actually have an old mower have to do this to to start it up. I've been too lazy to really fix that problem since I don't use it often. You might want to fond something to use to blow into fuel line between it and your mouth, like a plastic tube or something similar just for health reason.

mikeinri · Aug 9, 2018

Thanks. Forgot to mention, it's not the gas cap. I loosened that, heard no vacuum, and the results didn't change. Then I took it off completely, same result.

Mike

cms1528 · Aug 9, 2018

Keep the cap on and blow into that fuel line.

Whirly · Aug 9, 2018

cms1528 said:
Keep the cap on and blow into that fuel line.

this will a cause all the fuel to go back in the tank.. it may clear the line of a blockage.. however when he goes for a restart the engine will have to fill the line again before it will start

Bill Kapaun · Aug 9, 2018

I'd spray some carb cleaner into the intake and see if the roughness "improves". That would indicate a fuel problem.

Are you sure both cylinders are firing? After a couple minutes of running, a bad cylinder may be cooler?
Maybe not a bad idea to pick up an inexpensive spark tester. It seems you work on enough of these to easily justify having one. maybe even 2 to compare both cylinders at the same time.
If it's a spark issue, disconnect the kill wires from the coils and see if it improves.

You might put the Briggs Model & Type in your sig. It would be much more informative than "2014 Intek".

slow wrench · Aug 9, 2018

We have simular tractors,my fuel filter always looks empty.I went through same thing last year,An easy MTF trick that I wish I would have done first,is remove bowel and spray carb cleaner with nozzle tube up main jet.Easy, and would have saved me a lot of time.

hotajax · Aug 9, 2018

Take the fuel line from the OUTPUT side of the fuel pump. Have someone crank a COLD engine, and see if gas shoots out of the fuel line coming from the pump. If you got gas shooting out, you got carb problems. Post 11 above looks right on the money. And see if there's crap blocking the needle valve seat. That's the first place the fuel goes from the fuel pump.

cms1528 · Aug 9, 2018

So, it's gravity fed and the engine or carb will still have fuel in it. First find out if you have fuel coming from the gas tank before you start testing down carburator or fuel pumps etc..

Nouveau Redneck · Aug 9, 2018

So, it's gravity fed and the engine or carb will still have fuel in it. First find out if you have fuel coming from the gas tank before you start testing down carburator or fuel pumps etc..

If it has a fuel pump it is not gravity fed. Performing the test of pulling the line off of the output of the fuel pump and cranking the starter will prove both whether there is fuel flowing from the tank to the pump and whether the pump is in fact pumping. If nothing comes out of the pump during that test then move back toward the tank in your diagnostics. If it is pumping fuel then you move toward the carb.

JP Savage · Aug 9, 2018

Sorry to hear you are having trouble Mike.

mikeinri said:
Thanks guys. Yes, the filter is between the tank and pump. Mike

Read cms1528 post from 5:30AM today. He explains it well.

Then he steps in again.

cms1528 said:
Keep the cap on and blow into that fuel line.

Personally I 'd take the cap off. But to each their own.

Whirly said:
this will a cause all the fuel to go back in the tank.. it may clear the line of a blockage.. however when he goes for a restart the engine will have to fill the line again before it will start

I have to give Whirly a hard time.:tango_face_devil:
Au contraire, mon frère.
If the filter is between the tank and pump and you disconnect the fuel line from the filter, fuel should run out if line is held down lower than the tank.
If no fuel flows, it is blocked. If you then push air towards the tank, and it clears a blockage, fuel will refill the hose, and run out the end before you can reattach it to the filter. Will mean the tank needs to be cleaned. And or that part of the fuel line has gone soft inside, is deteriorating, and needs to be replaced. I had to replace that hunk of line 2 years ago on my GT. Line was bad and fuel slowed, then just stopped flowing altogether when removed from filter.

Whirly · Aug 10, 2018

JP Savage said:
Sorry to hear you are having trouble Mike.

Read cms1528 post from 5:30AM today. He explains it well.

Then he steps in again. Personally I 'd take the cap off. But to each their own.

I have to give Whirly a hard time.:tango_face_devil:
Au contraire, mon frère.
If the filter is between the tank and pump and you disconnect the fuel line from the filter, fuel should run out if line is held down lower than the tank.
If no fuel flows, it is blocked. If you then push air towards the tank, and it clears a blockage, fuel will refill the hose, and run out the end before you can reattach it to the filter. Will mean the tank needs to be cleaned. And or that part of the fuel line has gone soft inside, is deteriorating, and needs to be replaced. I had to replace that hunk of line 2 years ago on my GT. Line was bad and fuel slowed, then just stopped flowing altogether when removed from filter.

the fuel flow may not happen if the outlet of the tank is on the top side & has a tube on the inside.. there r tanks with the flow from the bottom side too like a lil spout..

Whirly · Aug 10, 2018

fuel pumps r put on tractors that have the tanks under the seat.. u do not need a pump on a gravity system.. a tank with the outlet on the bottom can make a flow of gas if u hold it lower than the tank.. when the outlet of the tank is on top & u brake the connection of the fuel line to the pump.. the gas will go back into the tank.. u can put a wrag over the hole U fill from.. then blow with ur mouth.. u might get gas to flow..

ya gotta b big winded to do that... LOL

mikeinri · Aug 10, 2018

Thanks for all of the advice, guys. It will probably be next week (or maybe the week after) before I have time to look at this.

I thought about the running on one cylinder thing, but couldn't keep it running long enough to test it (the old-school way of removing one plug wire at a time).

I do believe that the hose connects to the bottom of the tank. I know that I've gravity-drained my tank on the Craftsman GT5000 (fraternal twin of this Husqy) by pulling the line off at the filter, and lowering it into a fuel can.

Given that the engine is so new (and immaculate), I'm leaning towards garbage in the tank and/or hose.

Mike

68Charger · Aug 10, 2018

Don't overlook your gas cap. Make sure its venting to avoid vacuum.

Whirly · Aug 10, 2018

68Charger said:
Don't overlook your gas cap. Make sure its venting to avoid vacuum.

go reread postin ## 7

Fuel blockage or bad pump or other?

mikeinri

dave_r

Whirly

iRodent

mikeinri

cms1528

mikeinri

cms1528

Whirly

Bill Kapaun

slow wrench

hotajax

cms1528

Nouveau Redneck

JP Savage

Whirly

Whirly

mikeinri

68Charger

Whirly

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