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dubaholic2
04-18-2010, 09:28 PM
scag sw36-13ka, kawasaki fc420v. just got it running and tried to use it for the first time and when i went to engage the blades the mower dies. no matter what i do everytime i engage the blades it dies. i figure there must be a safety or something thats not working correctly, but im not sure where it would be. if anyone can help with this i would greatly appreciate it. thanks, ian

DT Lawn Care
04-18-2010, 10:04 PM
scag sw36-13ka, kawasaki fc420v. just got it running and tried to use it for the first time and when i went to engage the blades the mower dies. no matter what i do everytime i engage the blades it dies. i figure there must be a safety or something thats not working correctly, but im not sure where it would be. if anyone can help with this i would greatly appreciate it. thanks, ian

Try choking it before and as you engage the blades. That will pretty much rule out any shot of engine failure. Electric or manual engage? Check your operator presence safety as well.

overtime mp
04-19-2010, 12:10 AM
This had happend on my deere. There was a bearing that was locked up so it would die. Can you spin the blades manual?

DaughtryLC
04-19-2010, 01:45 AM
i have an older toro that I have to half choke it everytime. Just one of those things

Outdoor_Maintenance_2010
04-19-2010, 05:50 PM
hope you dont have the engine running at high rpm's when you do so

Diesel59
04-19-2010, 10:33 PM
could be the safety switch on the handles.... they go bad from time to time. That is really the only thing that will kill the blades when you try and engage them.

dubaholic2
04-20-2010, 09:37 PM
the safety swith on the handles was bypassed long before i got the mower. as for the pulleys, i cant turn everything easily by hand. i have the mower running at full throttle when engaging the blades. should i not do this? i would imagine it would need the power to take the extra drag of the blades engaging. if im wrong please correct me and explain this to me. thanks, ian

piston slapper
04-21-2010, 03:58 PM
Applying the choke is a good way to troubleshoot . If you carb is running lean,(partially clogged) you wont have enough gas for the engine to handle the load of engaging the blades.

Top governed speed is ok to engage the blades, I dont think you're going to hurt the belts.

44DCNF
04-21-2010, 05:03 PM
Any wires going to the trans? If so remove the switch they go to and see if the ball on the end of it is free moving, or rusted or gone altogether. Both this and the one on the blade linkage work in concert. The trans switches tend to rust sitting on top of the trans and taking in water. They can eventually come apart when you shift into gear; sounds like your situation when you went to move it from behind the trailer.
A blown head gasket or loose spark plug will cause an engine to suffer under load too.
Synch your choke and throttle adjustment, if applicable.

44DCNF
04-21-2010, 05:48 PM
Any wires going to the trans? If so remove the switch they go to and see if the ball on the end of it is free moving, or rusted or gone altogether. Both this and the one on the blade linkage work in concert. The trans switches tend to rust sitting on top of the trans and taking in water. They can eventually come apart when you shift into gear; sounds like your situation when you went to move it from behind the trailer.
A blown head gasket or loose spark plug will cause an engine to suffer under load too.
Synch your choke and throttle adjustment, if applicable.

After rethinking this, it seems a failed neutral switch would prevent it from starting altogether, not kill it when blades engage. Might be worth a look though.

dubaholic2
04-21-2010, 09:07 PM
i tried choking it when engaging the blades, but it does the same thing. the switch on top of the tranny is just a 2 prong flat connector. i dont see any kind of ball... i also tried unplugging the one under the deck, but no difference. maybe i should try jumpering it?

44DCNF
04-21-2010, 10:14 PM
Either of these switches could be safely checked with a continuity tester (open/closed), volt meter when running, and physically for proper action. Otherwise and with caution, then yes, you can jump the connectors on the linkage switch first and see; unplugged could still be the same as connected to a broken switch depending how it is wired-if the switch is a normally open or normally closed. Be very careful-it could start in gear or with blades engaged when you jump the switches. Do this just to diagnose the problem and using extreme caution. DO NOT OERATE WITH BYPASSED SWITCHES.

Trans switch: If you disconnect the wires and remove the trans neutral switch, you'll see the ball end that was inside the trans...It's spring loaded and should move into the switch smoothly but firmly without hanging up, as the shift fan (part of the internal shift linkage) rides across it. What happens is the spring inside can rust and break.

44DCNF
04-21-2010, 10:26 PM
Just adding again, make absolutely sure your blades are not engaged and it is set in neutral before starting, if you jump switches.

piston slapper
04-22-2010, 08:59 AM
FC 420... If its a safety switch shutting the mower down, unplug the white wire coming from engine to the main harness. It should be next to the oil tube, leave the wires going into the motor hooked up.

dubaholic2
04-22-2010, 07:40 PM
undid the white wire and everything works fine (except for the key switch). mowed about 3/4 of my yard and the trans started chattering and wouldnt pull anymore. is the trans gone?

piston slapper
04-23-2010, 04:03 PM
Check your drive belt under the transmission, It wont make it chatter, but if its loose it wont move.

Chattering cant be good, something needs some grease or is worn out.

dubaholic2
04-24-2010, 12:58 PM
i looked at the trans and i didnt see anything that looked like a place to check or add any kind of fluid or grease. does it require disassembly to service?

DT Lawn Care
04-24-2010, 07:39 PM
i looked at the trans and i didnt see anything that looked like a place to check or add any kind of fluid or grease. does it require disassembly to service?

To pack grease IN it, you need to remove the top of the trans cover. I would check the keys while you have it off.

dubaholic2
04-24-2010, 07:43 PM
what do you mean by "keys"?

dubaholic2
04-24-2010, 09:08 PM
also, what type of grease do they take?

ABeautifulCutAboveInc.
04-25-2010, 10:58 AM
I had this happen to my hustler last year. I have an electric clutch, so when I engaged the blades it would die out. It was my battery. $60.00 fix and a little aggravation.

dubaholic2
04-25-2010, 05:16 PM
i got the blade problem fixed, thanks. also, mine has no battery...

bbirder
04-26-2010, 11:43 AM
My new Hustler with only 20 hrs. on it did that this year. Dealer said it had trash in the carb and charged me to clean it. I wasn't too happy. He didn't change or check the filter. How could trash get thru filter to cause carb problems. It's engaging now but I feel the engine is not getting the rpm's that it had before they messed with it. Also, how could it run fine with trash in the carb ,and only cause problems when the blade is engaged?