Do You Throttle All The Way Down Before Turning Off The Engine?

[djdicetn]

Thanks guys for the reassurance.

I was worried...

Kinda like me when user Carscw warned me about transporting my Gravely at minimum throttle causing damage to my hydros(or engine).......I only have about 60 hours on mine and also hope I didn't hurt anything:0(

 

[kwak]

I asked my dealer about engaging the blades and he said to do it a full throttle so that is what I do. I am guilty of not looking that up in my owners manual so I am not sure what Scag recommends. As far as turning the machine off I usually throttle down before killing it.

 

[cecjack1]

Having worked in aviation with piston engines and turbine engines, it has been for the longivity of piston engines to allow the engines to normalize from the extra heat generated in the working operation RPM by letting the lubricants (oil) disapate the built up heat from working and allowing the oil to disapate the extra heat. On Kubato ZTR Z331 manual suggests allowing engine to cool down for 2 minutes at a fast idle before shutting down. Allison Turbines learned the lesson years ago from bearing failures due to synthetic oil breakdown causing oil restrictions in the oil jets causing lack of lube to bearings. We had to cool down a full 2 minutes before shutting down. The oil temps would drop almost a 150 degress in that time. Makes sense to allow a piston engine the same previlage and adds to a longer lasting engine and transmission.


Cecil Jackson
Gravely 300 (2001 850 hours)
Kubota Z331 (2012 128 hours)
mowing 6 acres

 

[gfp55]

Having worked in aviation with piston engines and turbine engines, it has been for the longivity of piston engines to allow the engines to normalize from the extra heat generated in the working operation RPM by letting the lubricants (oil) disapate the built up heat from working and allowing the oil to disapate the extra heat. On Kubato ZTR Z331 manual suggests allowing engine to cool down for 2 minutes at a fast idle before shutting down. Allison Turbines learned the lesson years ago from bearing failures due to synthetic oil breakdown causing oil restrictions in the oil jets causing lack of lube to bearings. We had to cool down a full 2 minutes before shutting down. The oil temps would drop almost a 150 degress in that time. Makes sense to allow a piston engine the same previlage and adds to a longer lasting engine and transmission.


Cecil Jackson
Gravely 300 (2001 850 hours)
Kubota Z331 (2012 128 hours)
mowing 6 acres

I have to thank you for joining this forum and for sharing your mind. I like your post. Keep it up. gfp55

 

[cooper714]

I have a Kohler 25hp on my Exmark Lazer Z. If I don't idle down for at least 45 seconds before I turn it off it back fires. I know guys that never idle down their Kohlers and they all seem to need top end rebuilds after about 4 years of service. Mine lasted 8 years. Just coincedence ? I don't think so.

 

[Nwatson99]

I park my ZT and let it run at full throttle for right at a minute to blow away any higher heat from traveling off the engine, then I idle down for the engine to get that low soft running / idle sound before shutting off the engine.

 

[gfp55]

I have a Kohler 25hp on my Exmark Lazer Z. If I don't idle down for at least 45 seconds before I turn it off it back fires. I know guys that never idle down their Kohlers and they all seem to need top end rebuilds after about 4 years of service. Mine lasted 8 years. Just coincedence ? I don't think so.

Your smart for doing that. There is a thread on this forum with a guy with a Honda that blow a hole in the side of his engine with 2100 hours. He found out from a dealer he was shutting his engine down wrong because he was turn off the key at full throttle. He learned the hard way. More should read that thread and learn. "But thats just me"

 

[Carscw]

Past few weeks I just drive up on the trailer and shut it off. LOL

What I do is shut the blades off drive to the trailer then on to the trailer lower the deck then shut it off.
It has ran with no heavy load as I drive to the trailer.

I drop down to a idle then shut off all in one motion.

 

[Col F]

Direct quote from the Briggs & Stratton Operator's Manual for the Model 310000 / 330000 series (19HP engine on Sears/Husqvarna), "How To Stop Engine - 1. With the throttle in the Fast position, turn the key switch to the Off position. Remove the key".

(Prior to reading this instruction for the engine on my newest machine, I always had reduced engines to low speed idle prior to shutting them off. For this new engine I have tried to remember to follow the B&S instruction, which I presume has some legitimate basis).

 

[arielredhunter2]

Thanks to everyone for your helpful/educational information.

I'm still learning...

I worked for International Harvester for about 10 years, and the reccomended procedure was to run the engine with no load for 5 minutes at just above an idle, before shutdown. Air cooled engine, same procedure, but at 1/2 maximum RPM. This ensures good airflow through the engine. The reason for the 5 minutes-no load is to stabilize engine temperatures before shutdown. Exhaust valve and exhaust chest areas are running much higher temperatures during high load operation. Driving the tractor (or truck) home to the barn, with the mower deck off, at 1/2 rpm would be considered part of the 5 minute regimen under IH Warrenty.