Running a new engine with no load - bad?

[SteveD2]

I've got a brand new 5.5hp steel bore Intek engine that I won't be using for a couple of months. I want to start it up and hear it run...would it be a bad idea to run this engine with no load, since it's not broken in?

 

[Propflux01]

Here is a similar thread concerning this subject.


http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=14;t=000280

 

[Ugly3]

Yes, much better to break it in under a load.

 

[SteveD2]

I don't want to break it in...just run it for about 10 minutes, little more than idle.

 

[harrydog]

I think running it at full throttle while NOT under load, before it's broken in, is what's not recommended.

 

[cryptokid]

running a new motorn at no load is the worst thing you can do for breaking it in. if you want to hear it run just start it and hear it for a couple seconda and shut down.

wait untill you are going to use it.

 

[NThomas]

i dont see the problem with running it now. The engine should run at about 3200 rpm. Run it at full throttle, all you are getting by goin under a load is letting more gas in the chamber.

Take a look at generators, if its under a load its trying to produce more power than it can handle. You dont worry about generators with a breakin, Why any other engine? Alot are the same.

 

[HEV]

NTHOMAS,

Just a quick question. I've got a Honda Harmony (plastic deck) with the 5.5 HP GCV160 motor. It runs at about 3090 rpm at unloaded WOT or blade clutch engaged loaded. Looking at the Honda power curves, there is no way this motor is making 5.5 HP at this speed, though it is making max torque. The max WOT rpm for this motor is listed at 3600. Should I tighten up the govenor spring a bit to increase the speed a bit? Is it safe? At times it seems under powered; it will stall at times when engaging the clutch.

Thanks.

 

[Bill Kapaun]

quote:

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Originally posted by HEV:
NTHOMAS,

Just a quick question. I've got a Honda Harmony (plastic deck) with the 5.5 HP GCV160 motor. It runs at about 3090 rpm at unloaded WOT or blade clutch engaged loaded. Looking at the Honda power curves, there is no way this motor is making 5.5 HP at this speed, though it is making max torque. The max WOT rpm for this motor is listed at 3600. Should I tighten up the govenor spring a bit to increase the speed a bit? Is it safe? At times it seems under powered; it will stall at times when engaging the clutch.

Thanks.

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"Horsepower ratings (shown as gross) are in accordance with Society of Automotive Engineers Small Engine Test Code J1995. Actual engine horsepower is lower and affected by, but not limited to, accessories (air cleaner, exhaust, charging, cooling, fuel pump, etc.), application, engine speed and ambient operating conditions (temperature, humidity and altitude)."

I don't know of any lawnmower engine that isn't overated this way.
Blade tip speed is the controlling factor. Something like 18,000 FPM.
However, I think 3200 RPM is safe for your engine.
My HR215SXA manual specifies the ground speed @ 3100 RPM however.

 

[Steve S]

It is a lawn mower, do what you want with it.

 

[NThomas]

I adjust most to 3200. Any more and engine life will suffer.

Set it at 3200 and you will be fine!

 

[SteveD2]

I was just reading the manual from the racing version of this engine. It says for break in to let it run for 8 minutes with no load, let cool down, and repeat.

 

[HEV]

Thanks Guys.

 

[hayabusa43]

Yes coming from a motorcycle background we all believe in doing 4 or 5 heat cycles. So on my new mower i cut the backyard and then complete cool down and then the front the same way. The next 2 days i ran the mower under no load for for 1> 5 min heat cycles each day.

After 2 more lawn cuts i will drop the oil. I was told from many engine builders that heat cycles work great to build strong motors FOR MOTOECYCLES not sure about how important on a small engine of a lawn mower. Just old habits i guess.

 

[Steve S]

Run it .How will it hurt anything .

 

[Brett Miller]

Best thing to do is start mowing right away. Running without load may not allow the rings to seat properly.

 

[doitmyself]

Here's the Briggs site opinion about engine break-in.

Quote:

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In general, there is no special engine operation procedure required during the break-in period. Break-in period is accomplished at any speed above idle and may occur faster if the engine is operated at varying loads and speeds. However, break-in occurs at an acceptable rate if the engine is operated at slightly less than top no-load speed with or without a moderate load. Combustion pressures at this speed are sufficiently high to cause piston rings to conform to the cylinder wall. It is recommended that an engine not be operated continuously at full load during the initial hours of operation. This can lead to permanent deformation of the cylinder bore.

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- no special procedures, above idle, and not operate continuous at full load initially seem to be the key points. In other words, just use it.

I would add that it never hurts to let it warm up a few minutes before putting under load/full throttle.