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It’s a good idea to check the engine speed of any new mower. There are occasions when the mower’s engine speed is not set to the manufacturers specifications. You can have the dealer verify the full throttle RPMs before taking delivery.

I assumed that my Gravely dealer checked the low idle RPMs and no load WOT RPMs before I took delivery. I specifically told them I wanted it checked before my purchase. I sensed that it wasn’t set right. I finally got around to checking it. Sure enough, WOT was below 3,400 RPM at no load. I pulled part of the rear bumper off to get at the linkage. It is now set to the Kohler specifications outlined in the ZT740 service manual. It’s dead on 3,600 at WOT and 1,450 with the Governor linkage away from the carburetor. It’s running really good.

MParr said:

I assumed that my Gravely dealer checked the low idle RPMs and no load WOT RPMs before I took delivery. I specifically told them I wanted it checked before my purchase. I sensed that it wasn’t set right. I finally got around to checking it. Sure enough, WOT was below 3,400 RPM at no load. I pulled part of the rear bumper off to get at the linkage. It is now set to the Kohler specifications outlined in the ZT740 service manual. It’s dead on 3,600 at WOT and 1,450 with the Governor linkage away from the carburetor. It’s running really good.

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Idle is usually 1850 RPMs and on newer (less than 10 years), often around 3250 wide open throttle. Maximum RPM for small engines is 3600.

Just because the service manual says 3600 rpm doesn't mean that your particular was spec'd to be set at that speed. Here I look up the engine per their spec numbers on the Kohler's dealer website.

And setting the speed the engine's spec can cause other problems as the equipment manufacture was keeping things within the max rpm limit for the hydros and the deck blade tip speed. Running the hydros above their safe rpm can lead to early failure just like running a sustain minimum speed.

Examples of a few of KT740s is

Before I made the adjustment, I contacted Ariens customer service to confirm.
The idle speed is set exactly as the same as the KT740. This idle speed was noted in the ZT740 service manual. It could have something to do with the engine application. The KT740 is usually mounted on residential units with residential hydrostatic transaxles. I have Hydo-Gear ZT5400s in my unit. The engine on my Gravely is a ZT740-3046.

@StarTech
If you find something other than what I’ve found, I can dial it back.
Gravely Pro Turn 260 (model #992267 serial #094036).
Kohler ZT740-3046
Hydro-Gear ZT5400

When I do a PDI on a new mower I always Check the top no load speed, idle speed. Along with all the other things I check. Loose Hydro bolts, lug nuts, engine mounting bolts, tire pressure, engine oil, seat bolts and various other things. Good to go and don't come back.

hlw49 said:

When I do a PDI on a new mower I always Check the top no load speed, idle speed. Along with all the other things I check. Loose Hydro bolts, lug nuts, engine mounting bolts, tire pressure, engine oil, seat bolts and various other things. Good to go and don't come back.

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I asked my Gravely dealer specifically to check the no load full throttle and idle speed. I don’t think it was done. I suspected the WOT speed was low. I have some Common Bermuda Grass over my septic drain field. It’s really thick and I’ve noticed the engine wasn’t performing as it should. When cut, the grass had a burned look to it. The engine did fine on the rest of the yard. My neighbor has a Bad Boy Maverick with the same engine and his unit is screaming. My ears told me that he was turning more RPMs at WOT. The landscaper who cuts the property next door runs Exmarks with Kawasaki engines. Their engines sounded to be running faster at WOT.
Every dealer should do as you do on PDIs.

For your particular spec you set it right. Just like to check things before I type specs. Just too variables to remember off the top of things. I rather look bad by posting the right info then post bad info.

StarTech said:

For your particular spec you set it right. Just like to check things before I type specs. Just too variables to remember off the top of things. I rather look bad by posting the right info then post bad info.

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Thanks @StarTech!
I wouldn’t think that Gravely would set the WOT RPMs any different on the Kohler ZT740 than the Kawasaki FX850V. The blade tip speeds should match across the Pro Turn 260 models.
The engine may have been set to the 7000 series specifications before it left the Kohler factory.
Or, it was set wrong somewhere along the line. Anyway, it’s dead on now.
Again, thank you so much for the confirmation.

CAUTION
Do not adjust high idle speed with the air cleaner
removed.

7394 said:

CAUTION
Do not adjust high idle speed with the air cleaner
removed.

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Correct! You don’t want trash sucked into the engine.
Yesterday was my first mow after the adjustments. The performance was much better. It powered through the thick Common Bermuda really well. The grass discharge was farther. And, not a single seed head of Bahia grass was left standing. I was using OEM Gravely blades.
Some people may change the style of blades to achieve the desired results, when the engine isn’t set to the manufacturers specifications.

MParr said:

You can have the dealer verify the full throttle RPMs before taking delivery.

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Nit picking RPM is a excellent way to piss your dealer off .

SeniorCitizen said:

Nit picking RPM is a excellent way to piss your dealer off .

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Then maybe you have the wrong dealer..

We do a PDI pre delivery inspections on all the mowers we sell and set the Top no load speed on all out mowers.

7394 said:

Then maybe you have the wrong dealer..

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That's the point , but there's none available it won't piss off .

SeniorCitizen said:

That's the point , but there's none available it won't piss off .

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If a customer asked me to check the engine RPMs on their equipment, I would make a note of it, and do it. It would not “piss me off” at all.

Yep.

SeniorCitizen said:

Nit picking RPM is a excellent way to piss your dealer off .

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Really? It only takes a minute to verify. It will piss him off real bad when you ask him to give the check back.

MParr said:

It will piss him off real bad when you ask him to give the check back.

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You got that right...........