SV610-3213 Fuel Delivery Problem?

[The Push mower]

Engine starts OK, but dies when the blades are engaged. Checked seat safety switch, replaced carburetor and removed fuel cap- none of these made a difference. If I turn the blades off quickly and throttle to choke the engine will continue running, so it appears the engine is not getting enough fuel. If it dies after blade engagement it will only restart with full choke and then doesn't want to run unless full choke. Let it sit for 10-15 minutes and the condition improves and I can ride around the yard with blades off. Checked service manual but it does not specify if this mower should have a fuel pump or not-this mower (Husqvarana YTH21K46; 960450026) does not have a fuel pump.


I am puzzled. Camshaft maybe? Greatly appreciate suggestions. Thanks in advance.

 

[bertsmobile1]

If it stops just like you have turned the engine off then chances are it is an electrical fault

If it is electrical then 2 things come to mind based on your post
1) problem with the seat switch or the wiring to / from the switch . Very likely
2) voltage drop causing the fuel solenoid to shut down unlikely but has been know to happen .

 

[The Push mower]

If it stops just like you have turned the engine off then chances are it is an electrical fault

If it is electrical then 2 things come to mind based on your post
1) problem with the seat switch or the wiring to / from the switch . Very likely
2) voltage drop causing the fuel solenoid to shut down unlikely but has been know to happen .

Thanks for the reply/suggestions. If I spray carb cleaner in it the engine will take off again. I will go through and check connectors and wires. This morning I started engine and let it idle with blades engaged for 10 minutes then increased engine speed then it died. I am puzzled.

 

[bertsmobile1]

So you write TV murder show scripts for living do you ?
Please put all of the observations in the original post.
Don't introduce new clues just after we have worked out who the murderer is
In that case I would be looking at a voltage drop and possibly a bad clutch which is drawing too much power .
The carb solenoid needs to see around 9V to stay open .
A bit hard to test unless you replace the solenoid with a short bolt then watch it t see if it springs open when the blades are engaged .I will not suggest clipping the plunger off because that illegal and it serves as a useful back up should the kill wire on the magneto fail ( happens ) .

 

[The Push mower]

Blade engagement is mechanical.

 

[bertsmobile1]

Well that changes everything
Start the engine then set the brake, slip round to the side and push the governor arm with your finger
If the engine dies then you do have a fuel supply problem.
BAd filter or debris in the fuel outlet spiggot in the tank would be the chief suspects .

 

[The Push mower]

Removed tank, and verified that I do not have any blockage from the fuel tank through rubber line as it connects to the carburetor. Next, I checked the fuel solenoid and it has 13.7-14.0v at WOT when the engine is acting up and cutting out.
Moving governor works fine when the engine decides to run right, but when it is not running right the governor doesn't really make a difference when it is moved manually. Engine still wants to cut out and die.

At high RPMs with blades engaged it runs terrible and can barely keep it running. At low (near idle) RPMs it is much better even with blades engaged. With blades off it will run at WOT and idle seemingly for a long time-in fact I don't recall it ever cutting at at WOT with blades off unless you engage blades then the mower totally loses it's sanity.

After it dies, it does not want to restart even with choke (usually) unless you let it sit for a few seconds. Then it restarts and repeats the same weird cycle.
Kinda hard to get a fix on this problem and describe it here.

 

[StarTech]

Sounds like a main jet blockage like trash in the carburetor fuel bowl. When you mower is just running without the blades engage it is just running off the idle mixture even at full throttle. Then you engage the deck it starts using the main mixture jet.

Also note some these engine where prone to fuel vapor lock once the engine was hot which is why they added a heat shield at the Walbro carburetor. I have seen fuel to be boiling at times especially if you are using winter fuel in the Spring time. It can boil as low as 140F.

 

[Hammermechanicman]

Star is right. You have a fuel delivery problem. The carb is running out of fuel or vapor locking. Biggest clue is engine doesn't want to restart after dying because the carb is empty. You say no fuel pump so it is gravity fed. Do you have an inline fuel filter? If so remove it and see what happens. The wrong fuel filter on gravity fed carbs can do exactly what you are describing.

 

[ILENGINE]

Also check the ground wire connector from the fuel solenoid where it bolts the plastic carb isolator to the block. That bolt will come loose and allow an air leak between the isolator and the block. The single courage used one bolt for the carb into the block and the other one is square headed into the back of that plastic carb spacer. If the solenoid ground bolt comes loose the whole carb is basically loose.

@StarTech Never saw any with vapor lock issues with that engine, but have had a few that melted the solenoid wires and Kohler blamed MTD for putting a muffler 4 inches from the carb without a heat shield, and MTD blamed Kohler for overcharging voltage regulator cooking the wires. Neither one would pay for a warranty claim on that engine with solenoid problems.