Export thread

Bought my Husquavarna 6021P 7 years ago. It has a Kohler courage XT6 engine (Kohler model number 917.384513) 149 CC
It worked flawlessly for 2 years. On the third year it started stumbling, especially when pointed uphill. I investigated and found there was an in filter in the fuel line. Removed it and replace with a larger filter. Also added a shutoff valve so I could run the fuel bowl dry at the end of each season. It worked flawlessly for another 5 years. Last fall it again started doing the same thing. In the middle of mowing it would stall. Pulling to restart it would run briefly and then stop. If I let it sit 20 minutes it would run run for a while then stop. Sometimes I can even finish the lawn in one session . Over the winter I did the following:

1 Discarded the old fuel and bought fresh fuel, added stabilizer.
2. Replaced the fuel filter with a smaller one to eliminate a low spot in the fuel line
3. Purchased and installed a carb kit
4. Replaced the old fuel lines.

It ran fine for the first 2 cuttings. Now its back to its old tricks. I'm at a loss to explain what is happening much less why. Anyone that has successful repaired similar issues i would appreciuate your input.

● Faulty carburetor.
● Faulty cylinder head gasket.
● Faulty or misadjusted choke or throttle controls.
● Fuel pump malfunction-vacuum hose clogged or
leaking. ● Intake system leak.
● Loose wires or connections that intermittently ground
ignition kill circuit. ● Quality of fuel (dirt, water, stale, mixture).
● Restricted fuel tank cap vent.

From the Kohler manual troubleshooting page for this engine, regarding starting but wont stay running.

Have you ever removed the blower housing to make sure the engine & cylinder fins are clean ?

That may not be your problem, but it is good maintenance.

Scrubcadet10 said:

● Faulty carburetor.
● Faulty cylinder head gasket.
● Faulty or misadjusted choke or throttle controls.
● Fuel pump malfunction-vacuum hose clogged or
leaking. ● Intake system leak.
● Loose wires or connections that intermittently ground
ignition kill circuit. ● Quality of fuel (dirt, water, stale, mixture).
● Restricted fuel tank cap vent.

From the Kohler manual troubleshooting page for this engine, regarding starting but won't stay running.

Click to expand...

If head gasket, i assume it would consistently not run, instead of run for 20 minutes then stop, then start again.
Choke and throttle control, I'll take a look. (there are no carb adjustments aside from Idle speed)
intake system leak: carb kit included all gaskets which have been replaced. I'll check the vaccuum hose.
loose wires: i'l take a look
fuel is fresh this spring and has been treated with stabilizer. I buy fresh *most* seasons
fuel tank vent cap: I'm looking at now.There is a rubber boot in the cap with a hole in the center. However, when I squirt carb cleaner into the hole it comes out the edges of the gasket only, which appers to seal against the filler neck. I can't figure out how its supposed to vent. Next time it stalls I'll loosen the cap and try restarting immediately. If that works I'll buy an aftermarket cap or drill my own vent hole.

Doesn't have a fuel pump, its gravity fed.

Update: started it to cut the lawn a moment ago. I did exactly 2 passes and it died again. Put it back on a level surface and removed the fuel cap. Tried to start with the same result. Dan for 5 seconds and then quit again. Still searching.

I battled with something similar for 2 years.

Finally, I spent $33 for a new carburetor on ebay and the mower runs like a champ again.

Try to replace the entire carb as it seems like a fuel delivery problem.

Best,

Dave

Thanks. Ordered a moment ago. I've removed and reinstalled the carb several times so it shouldn't be a problem to install, assuming any adapter plates/fittings etc move over from the old to new carb in an orderly manner. After the mowereis running I will disassemble the old carb and see if I can spot the problem for future reference.

Reading over the other threads on the kohler forum, it seems a lot of people with ahem... mature Kohler mowers are replacing carburetors. Anyone care to speculate why? Anything to do/avoid to prevent re occurrence in the future? I have begun using a fuel conditioner, and running the fuel bowl dry after each use. Any thoughts?

Because they are too lazy to clean their old carb properly .
Because they are too impatient to properly diagnose the problem
Because they feel it is too complicated.
And mainly because there are so many garbage carbs on the web really cheap so people think they have one upped those thieving incompetant repair technicians.
And most come back a bit latter on because the carb was not the problem in the first place.

With a problem like yours you need first to find out why the mower stops.
And you start that by working out weather it is a fuel problem or an electrical problem.

So the first thing is to arm yourself with a can of carb cleaner and 1 or 2 inline spark testers, the red flashing light type.
You fit the spark testers pop the can of carb cleaner in your pocket & go mow.
The instant it stops you check the spark testers .
Flashing OK = not an ignition problem

You then slip off the air filter and spray some carb cleaner down the carb throat.
If the engine fire right up and you can keep it running with short shots carb cleaner down the throat then you have a FUEL SUPPLY problem.

If neither make any difference then you have an overheating problem.

Once you have established which section of the engine is causing the problem, you then start looking for the reason.

Your symptoms would typically point to a blocked tank breather or a plug being formed by floating debris in the tank.
A fault in the magneto coils or plain overheating

I use only 100% gas, I think the E-10 is evil...

update: I siphoned the fuel out of the tank, then swished the remaining fuel around and poured all the fuel into a jar through a coffee filter. No sediment. Poured the fuel back into the tank. Installed the new carb. I have now cut the entire lawn twice with no stalls. If i get onemore cutting I'll call it a solve. I plan to disassemble the old carb and see if I can sleuth out the problem.

7394 said:

I use only 100% gas, I think the E-10 is evil...

Click to expand...

What do you think the E stands for!?!? :laughing::laughing:

Scrubcadet10 said:

What do you think the E stands for!?!? :laughing::laughing:

Click to expand...

Evil of course.. :laughing:

7394 said:

I use only 100% gas, I think the E-10 is evil...

Click to expand...

Where do you find straight gas? All the pump gas in my area is E80

ras_oscar said:

Where do you find straight gas? All the pump gas in my area is E80

Click to expand...

https://www.pure-gas.org/index.jsp?stateprov=MD