Winding down the engine speed on a briggs stratton mower

[ATC1983]

Hi

 

Need advice again - Have just used the big mower for the first time commercially today and have got it working great save for the fact that it's drinking petrol like there's no tomorrow. It's going through about £3 worth every half hour and needing refilling. Just wanted to know if this is the normal rate, and if it's possible to make it so the engine speed declines? I think this setting is quite high on the machine as when I use the automated bar it shoots off ultra quick.

 

 

On another note lost the £40 I earnt from my only job today so am inconsolate:sad:

[Pedroski]

Haven't you got a 'tortoise and hare' lever on it?

 

Which mower is it? We've use a Hayter with a Briggs and Stratton engine and it only sips fuel.

 

Mind you, at the prices of fuel it's not surprising how much money gets spent on it. Just another cost that you need to factor in doing business, and why it's pointless mowing a lawn for a fiver.

[ATC1983]

It's b/s 500 series - not sure of the exact model - had a look at it earlier and couldn't see any adjustment lever. This was really drinking the fuel up, and it speeds forward if we use the self-propelled lever, so am assuming it's overcharged.

 

Just reading about adjusting the governor screw - needless to say am not keen on this as it may invalidate my warranty.

[ATC1983]

I see what you mean now re doing it for a fiver. The lawn I did was soaking and overgrown. But this was the first job I'd tried to use the petrol mower on - I'd been using a mechanical one, still good, but slow - so inevitably it kept jamming, then I reset the wheels, and dumped the collector, and it worked great, just eating too much petroleum.

 

Then I lost my cash. Gutted.

[GardenKit]

Most petrol rotary mowers are rated at 2800 or 2900 rpm. This is mostly due to noise legislation as most of the noise comes from the blade.

 

The problem with this is that most mowers just wont perform at these low revs. They dont cut cleanly and wont collect well. They ideally need to be a bit faster.

 

Most engines though, are happy to work at up to 3600 rpm, so its not unusual to see mowers set at around 3000 to 3200 rpm to achieve peak performance.

 

As higher speed equals lower torque, the consumption of fuel on a revving engine should not be much greater than on a lower revving, labouring, engine.

 

Sure, it may invalidate warranty to increase the revs, but only on a technicality, it wont harm the engine.

 

Many mowers nowadays do not have a variable throttle control as there is no point in operating at reduced revs, they simply do not perform.

 

Adjustments to top speed are made by increasing the load on the spring linking the throttle lever to the governor arm. The governor is constantly striving to shut the engine down, so the spring tension gives more load to the governor arm, keeping the revs up.

 

Of course, I dont condone altering the engine speed from that on the rating plate

Edited July 18, 2012 by GardenKit