# Rider bogs down when blade is engaged



## DR_N_SC

I have read through many post and followed suggestion's and learned a lot however I am still experiencing a problem. 

I have a Murry rider with a 13HP OHV Enduro / Tecumseh and a 40" cut
I have ops checked the seat switch, while the mower is running the seat does not have to be occupied unless the blade is engaged. then you have to be on the seat. so I am assuming it is working properly. 

I have recently replaced both the right and the left mandrel's and the belt moves freely when not engaged so the bearings look fine. I also replaced the baldes when I changed out the mandrels. I have no string or rope or twine that might bind the baldes. 

I removed the air filter (to see if a drity filter might be the problem) still no effect. 

Ok here is the issue. On start up all is fine, both sitting and moving blades dis-engaged all is fine. once you engage the blades you can mow but you are rolling the dice as to how far you can go, before it starts to choke down, you dis-engage the blades and sit for a moment and then you repeat till the yard is done. Oil level is fine and new. 

Only thing that might be different is the engine seems to be running hotter. of course I have never guaged the engine temp before and the weather is abnormally hot. so this may just be me looking for a way to explain WTH is going on.  so if you have any ideas plz dont hesitate to share. 

Thanks Don


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## 30yearTech

Sounds like there could possibly be some water or debris in the carburetor, or possibly even a bad spark plug.


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## DR_N_SC

*New Problem*

Thank you for the reply about the spark plug, I let the mower sit and cool off after I mowed the yard and changed the plug the following day, but when I got on it to start it nothing happened. ( I mean nothing) so I checked the battery, 12.8v I checked the fuse on the outbound side of the solenoid both checked fine. 

I am able to start the mower by bypassing the solenoid and the key switch by using a set of jumper cables and the frame as a ground and jumping straight to the coil/starter on the side of the engine, once running I can turn the lights on and off, and finish mowing the yard. and I can even use the key to turn the mower off. but I can not start it unless I jump start it as as mentioned above. 

So do I have a bad ignition switch or a bad solenoid. ( I also removed the selonoiod and sanded the contacts on both mower and solenoid for better ground.) 

as for the new spark plug taking care of the original problem it did not, I also replaced the fuel with new, and drained the line to the filter and tapped as much debris out of the in line fuel filter as I could, I am going to get a new one tomorrow, as well as either a new ignition switch or a solenoid based on your responses. Hopefully the fuel filter is the underlying reason it is dying with a load present. 

Thanks again, I have enjoyed tearing this thing apart and learning alittle more about the mower and honestly a little more about my self.


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## DR_N_SC

*pdf checklist*

I found the follwoing PDF checklist very helpful and wanted to share 

http://www4.briggsandstratton.com/m...rical from MA-S-1612 2004 Quick Reference.pdf


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## 30yearTech

DR_N_SC said:


> Thank you for the reply about the spark plug, I let the mower sit and cool off after I mowed the yard and changed the plug the following day, but when I got on it to start it nothing happened. ( I mean nothing) so I checked the battery, 12.8v I checked the fuse on the outbound side of the solenoid both checked fine.
> 
> I am able to start the mower by bypassing the solenoid and the key switch by using a set of jumper cables and the frame as a ground and jumping straight to the coil/starter on the side of the engine, once running I can turn the lights on and off, and finish mowing the yard. and I can even use the key to turn the mower off. but I can not start it unless I jump start it as as mentioned above.
> 
> So do I have a bad ignition switch or a bad solenoid. ( I also removed the selonoiod and sanded the contacts on both mower and solenoid for better ground.)
> 
> as for the new spark plug taking care of the original problem it did not, I also replaced the fuel with new, and drained the line to the filter and tapped as much debris out of the in line fuel filter as I could, I am going to get a new one tomorrow, as well as either a new ignition switch or a solenoid based on your responses. Hopefully the fuel filter is the underlying reason it is dying with a load present.
> 
> Thanks again, I have enjoyed tearing this thing apart and learning alittle more about the mower and honestly a little more about my self.


It could be the ignition switch or solenoid, but there are also switches on the clutch and blade engagement that interlock the starter. If either one of these switches is bad, then the solenoid will not get energized.

You need to check to see if power is getting to terminal on the side of the starter solenoid when the key is in the start position with the clutch pedal depressed and the blades fully disengaged. If no power is being delivered to the solenoid, then you need to trace power from the ignition switch and trough the blade and clutch switches to see if there is any break at either of those points. You also need to check and make sure power is getting to the ignition switch. 

Most ignition switches are marked on the back side with letters. Terminal marked with a "B" is for battery power coming in, Terminal marked "S" is for power out when the key is in the start position.


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## 440s-4ever

Take one jumper cable and go from the battery + to the "S" terminal on the starter solenoid. If the engine cranks, you've got a bad switch. If it won't crank with power applied to the S post then you need a new solenoid. 

If the solenoid is bad, rap it with a hammer and try the key again. They're a mechanical switch inside and are prone to jamming up. It still needs replaced, but you'll have one more degree of assurance that you're replacing the bad part. 

As a side note, you may not actually need parts replaced. Look at your battery cable ends on the starter and solenoid. Corrosion can stop electricity in it's tracks, and can be somewhat unpredictable on things that vibrate as much as mowers. If you can access those nuts, loosen and retighten all those fittings, and give the ends a stout wiggle test by hand to be sure the wire's firmly attached to it's end. 

Good luck

PS- 
Solenoid 101. You know the clicking sound made when starting a car with a dead battery? Starter solenoids are the same no matter what. They have 2 high current lugs, and when you crank the engine, those 2 lugs connect to allow power to transfer thru the solenoid to the starter. When power is applied to the "s" post (turn the key), a small electromagnet inside the solenoid energizes. The clicking sound you hear is a slug of iron moving toward the magnet. That slug ends up completing the connection between the 2 high current lugs. 

The reason solenoids exist is to keep the starter's current out of the key switch. Nothing more. 

So if when trying to start your engine, you hear a click.....that's the solenoid's magnet moving the iron slug into place. It's working. If you don't hear a click, then it's either not getting power to the little post that controls the magnet, or the iron slug is jammed up inside the solenoid.

Get this figured out and you're also a master of starting old fords. They used a fender mounted solenoid that looks the same for about 50 years. I'm pretty sure the solenoid on my craftsman rider would directly interchange with a F150.


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## terry82

on the boging down when you ingage the electric clutch,have you checked the govener?and are you shure that that the motor is running good when the blades are not engaged ?on my rider i was having a problem like yours .the fuel filer was starving the motor when i engaged the mower deck .i changed filter all is well.


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## DR_N_SC

*Fuel FIlter*

Ok, thank you all for the tips. I have not attempted the + post to the switch yet. (just read post and yard is done for this week) but I will check that out today. as for the selinoid I have already tapped it a few times and no clicking, assuming its bad/stuck can a bad switch cause the selinoid to not get power and appear to be bad? 

I think the underlying problem for the bogging down is the clogged fuel filter, during the last attepmt to put fresh gas in the tank I noticed some small black things floating around in the bottom, after I drained the tank and started over when I went to fill the tank some this week I noticed more small black things. The underside of the gas cap's protective rubber seal had become brittle and was breaking up and falling into the tank from the vibration. I have cleaned the remainder of the seal and drained the tank once again. and purged the line to the filter and blown out the filter as best I can. 

The mower ran fine today for about 45 min's the last 15 min's or so it started acting up again. We are making progress I am hoping after a new filter and a little more TLC all will be well again. Thanks again for your tips and tricks. 

Don


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