Raptor SD stalling when blades are engaged

Jimmy Perry

Forum Newbie
5.0 hrs on my new SD. It has been flawless. Today when I engaged the blades at half throttle the engine choked down and stopped. I was able to engage at a slightly higher rpm and keep running. What is causing this? Bad Fuel?? This motor has always sputtered at little on initial startup when the choke is applied but cleans itself out rather quickly. Any harm to engaging at 3/4 throttle? Thanks for any help. - JP
 
5.0 hrs on my new SD. It has been flawless. Today when I engaged the blades at half throttle the engine choked down and stopped. I was able to engage at a slightly higher rpm and keep running. What is causing this? Bad Fuel?? This motor has always sputtered at little on initial startup when the choke is applied but cleans itself out rather quickly. Any harm to engaging at 3/4 throttle? Thanks for any help. - JP

I always engage the PTO at 3/4 or full throttle. Most the time at full throttle as I engage and disengage a few times per yard.
 
Mine is much better after a minute of warm up. Then it will take a 1/2 to 2/3 throttle blade engagement. I start it up, drive it out to the front to start cutting, by that time (30 to 60 seconds) it's great.
 
5.0 hrs on my new SD. It has been flawless. Today when I engaged the blades at half throttle the engine choked down and stopped. I was able to engage at a slightly higher rpm and keep running. What is causing this? Bad Fuel?? This motor has always sputtered at little on initial startup when the choke is applied but cleans itself out rather quickly. Any harm to engaging at 3/4 throttle? Thanks for any help. - JP

Read your manual it will tell you to engage PTO at 3/4 or full throttle only or engine damage will happen.
 
Mine does it when engine cold. Let her warm up a couple on minutes. My manual says half throttle on my SD Raptor. It it starts to stall after engaging PTO, open the throttle.
 
I have the same model. The manual does state to engage at half throttle. However, at first engagement I typically start it about 2/3 to 3/4 throttle. After it has run a bit half or just a shade more works just fine.
 
Engine kills when I pull the steering arms in. if I hurry and put them out the engine will stay running, Sounds like it could be a safety switch but it happens on either one. not sure where these wires go but it could be a loose connection at that point. Thanks, If anyone has more suggestions please let me know.
 
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On most all air cooled mower engines, this is everyone of you reading this, it's been recommended to run the engine at full revs all the time. Why? For proper engine air cooling and lubrication. Briggs states max service life and durability when ran at max revs. As in 3200 to 3600rpm per your engine/mower manual at all times.

Just think on a mower with a dirty air filter or no valve adjustments ever, trying to dead start 2 or 3 blades at anything under 3/4 throttle.
 
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