Lawnmower will not run

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Bert has some great advice for you right there........ It is a great way to learn about these engines......

First thing you do is check the oil...... If it doesn't have any that's your culprit... I took one in a while back and it had a broken rod 3 pieces in the bottom of the sump....

If you had the govorner wide open holding it with a wire tie or a string that will do it to..... OVER revving will cause a rod to throw and break the block.........

I have seen that tooooo many times in my lifetime.............
 

ILENGINE

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Bert has some great advice for you right there........ It is a great way to learn about these engines......

First thing you do is check the oil...... If it doesn't have any that's your culprit... I took one in a while back and it had a broken rod 3 pieces in the bottom of the sump....

If you had the govorner wide open holding it with a wire tie or a string that will do it to..... OVER revving will cause a rod to throw and break the block.........

I have seen that tooooo many times in my lifetime.............

tying the throttle open to make the engine run faster for cutting high tough grass use to be very common for people to do. don't see it as much anymore. maybe because the newer engine come apart before they have a chance to run it very long.
 

PTmowerMech

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tying the throttle open to make the engine run faster for cutting high tough grass use to be very common for people to do. don't see it as much anymore. maybe because the newer engine come apart before they have a chance to run it very long.

Ya gotta admit though, some of those engines are set too low sometimes. You can attribute that to being a weak spring, in some cases. I'm guilty of bending something to increase the idle.
 

bertsmobile1

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It is all about blade tip speed and noise.
Hondas spin a bit slower down here ~ 3200 rpm which makes them a lot quieter.
One of the blue smokes went as low as 2750 to get the noise down.
 

ILENGINE

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Ya gotta admit though, some of those engines are set too low sometimes. You can attribute that to being a weak spring, in some cases. I'm guilty of bending something to increase the idle.

Engine rpm on a pushmower is based off of the length of the blade. The longer the blade the slower the engine runs. 19,000 FPM is the perceived maximum tip speed, and if turned to fast can create a harmonic in the blade causing cracking and blade destruction. That maximum speed is even used on rough cut mowers. A 8 foot rotary cutter may only turn at 900 rpm.
 

PTmowerMech

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Well, that's some good information. Thanks
 

Riley6411

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I did some research
I had the mower that now has a hole in the side running 3 days before with the muffler offf
Would that have anything to do with it now having a hole in the side and not running?
 
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So what your saying is ,,,,,,, that you are disassembling the engine that had a hole in it ????

I have ran small engine's with just a pipe sticking out for racing Sprint Karts.... Never a problem, but we would stick a cork in the pipe when we shut the engine's off......

Did you get your other engine going ???
 

bertsmobile1

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Engine rpm on a pushmower is based off of the length of the blade. The longer the blade the slower the engine runs. 19,000 FPM is the perceived maximum tip speed, and if turned to fast can create a harmonic in the blade causing cracking and blade destruction. That maximum speed is even used on rough cut mowers. A 8 foot rotary cutter may only turn at 900 rpm.

One of the many reasons why swing back blades are so much better for mowing with.
 

Riley6411

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So what your saying is ,,,,,,, that you are disassembling the engine that had a hole in it ????

I have ran small engine's with just a pipe sticking out for racing Sprint Karts.... Never a problem, but we would stick a cork in the pipe when we shut the engine's off......

Did you get your other engine going ???
Yes I did the head gasket was out of place/worn
So I replaced it and it runs well
 
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