Dies - Choke Very Touchy

masterdrago

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ZT3 with FS730V was running ~20-30 minutes then would die, fairly easy restart, then die in a bit. Changed filter, found debris in tank (crap in gas can from wasp in fill tube). Cleaned all, new filter. Only filtered gas now. Still dies after getting warm. New plugs, fuel pump, coils. Finally replaced carb. Now the choke is extremely touchy and will die if opened all the way. Have to manage choke as I mow. Then will suddenly die and will not start until several minutes. Then might run good for a while if choke is managed. Gas tank clean, new filter again. Does this sound like a defective carb (float)? How much better will the $377 carb from Parts Tree be than a $43 carb from AMZN? I really do not know the fix and looking for some help. Sort of hard now to mow 5 acres.
 

slomo

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Best to move this to the Kawi section.
FS730V was running ~20-30 minutes then would die, fairly easy restart, then die in a bit.
Sounds like she is thirsty. Lack of fuel delivery.
Changed filter
Should of tested your old filter first. Most likely needed a new one anyway.
found debris in tank (crap in gas can from wasp in fill tube)
Zero surprise here. Been preaching to all to get the new style fuel can spouts. They keep more trash and water out of the can. Feel the fuel stays fresher as well.??? Gas can needs to be spotless like a new one. You can buy the new style spouts easily.
Cleaned all,
Hope the gas can was on your list. All that trash in the can passed to the carb. Does it every time you refill.
New plugs, fuel pump, coils. Finally replaced carb.
All of these parts tested bad???? Sure hope you kept them all. Stop buying junk and test what you have. You NOW have 4 untested items on your list. New doesn't mean new anymore.

Pull the fuel hose off AT the carb inlet. Drain into a glass jar. Look for water and flow. Should have a nice gundy flow if you have a pump. Guessing you have a hose nipple clogged on the bottom of the tank outlet. Could be an fuel line internally collapsing on you.

Clean the tank and rod it out on the bottom outlet.
Install new fuel hose from tank to carb.
Could be a bad tank vent or fuel cap not venting.
 

Auto Doc's

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If you have to use the choke constantly, there is an air leak at the intake gaskets more than likely.
 

masterdrago

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If you have to use the choke constantly, there is an air leak at the intake gaskets more than likely.
Thanks Auto Doc's. I'll look at those gaskets next week. After I start the engine cold, I have to advance the choke to full open very, very slowly. Over about a 5-10 minute period as I'm mowing. If I do it too quickly,it runs rough and will eventually stall. Once it gets good and hot under heavy mowing load, it allows full open choke.

To answer slomow.... I too thought thirsty but if so wouldn't she crank easily after only sitting a minute or 2?

Old filter was needed to toss as some junk came out when back flushing.

The only gas cans I use are the Justrite 5 Gallon Type II Red Safety Gas Can for Gasoline with Flame Arrester, Self-Closing Lid, and 1" Flexible Metal Spout, Made in the USA, Galvanized Steel Flammable Storage Can, 7250130. I had allowed, unknowingly, the fill tube to become filled with grass from some sort of wasp nest. It got in the fuel tank and slowly worked its way into the black plastic pickup tube. This was my original fail. I had replaced two filters and found crud out of them when back-flushing. Started using a big metal funnel with a fine screen to filter gas after that.

Changed the pump as I kept having stall issues after ~20 minute mow. checked all the tubing by pulling a small vacuum.

Yes I kept the old coils and old carb which looked pretty new inside (I use Seafoam in summer and Marine Stabil in gas during long months not used. I do not use ethanol free gas. Unfortunately, I do not know how to "test" some parts.

I had suspected the gas cap being not breathing but found it clear.

I do regular oil changes (50hrs), air filter, tranny fluid, and yes, the air ports running down thru the engine are clean.

It's just the twichy nature of the choke setting. This afternoon, I mowed near a full tank of gas by slowly advancing the choke over ~10 minutes while mowing full power. Strangely, it never missed a beat. All this choke business began after replacing the carb. I have not the pay grade to rebuild the carb. Got a brand X from AMZN.
 

Tiger Small Engine

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Thanks Auto Doc's. I'll look at those gaskets next week. After I start the engine cold, I have to advance the choke to full open very, very slowly. Over about a 5-10 minute period as I'm mowing. If I do it too quickly,it runs rough and will eventually stall. Once it gets good and hot under heavy mowing load, it allows full open choke.

To answer slomow.... I too thought thirsty but if so wouldn't she crank easily after only sitting a minute or 2?

Old filter was needed to toss as some junk came out when back flushing.

The only gas cans I use are the Justrite 5 Gallon Type II Red Safety Gas Can for Gasoline with Flame Arrester, Self-Closing Lid, and 1" Flexible Metal Spout, Made in the USA, Galvanized Steel Flammable Storage Can, 7250130. I had allowed, unknowingly, the fill tube to become filled with grass from some sort of wasp nest. It got in the fuel tank and slowly worked its way into the black plastic pickup tube. This was my original fail. I had replaced two filters and found crud out of them when back-flushing. Started using a big metal funnel with a fine screen to filter gas after that.

Changed the pump as I kept having stall issues after ~20 minute mow. checked all the tubing by pulling a small vacuum.

Yes I kept the old coils and old carb which looked pretty new inside (I use Seafoam in summer and Marine Stabil in gas during long months not used. I do not use ethanol free gas. Unfortunately, I do not know how to "test" some parts.

I had suspected the gas cap being not breathing but found it clear.

I do regular oil changes (50hrs), air filter, tranny fluid, and yes, the air ports running down thru the engine are clean.

It's just the twichy nature of the choke setting. This afternoon, I mowed near a full tank of gas by slowly advancing the choke over ~10 minutes while mowing full power. Strangely, it never missed a beat. All this choke business began after replacing the carb. I have not the pay grade to rebuild the carb. Got a brand X from AMZN.
Clean original OEM thoroughly and reinstall. That step alone will most likely fix your problems. Also, blow back through fuel line to tank to clear blockage. Also, check fuel for water and crap in tank and siphon/drain and blow out as needed.
 

slomo

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Steel fuel can and E-10 is/can be a recipe for water. That's why I asked you to test for it.
 
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