Briggs& Stratton engine will not turn over

JimP2014

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Intake valve. The maximum travel out is 3 cm rocker arm

Intake valve travel comes up to 2 cm. Mark

Exhaust valve when it goes inside. It's at the 1. 2 CM Mark

Exhaust valve all the way out. It's at the 2.3 cm. Mark

Okay these are just raw notes. The way I'm measuring is I go to the cylinder head and I make the origin for measuring distance. The plate that contains the bolt for the rocker arm so that is exactly 0 in

So then I rotate the flywheel and I come up with how far does the rocker arm travel as measured from the rocker arm and the tappet so I'm measuring that side.

If there's any confusion on the way I did this, please ask. Thank you
I got to go back outside. I know the bottom one is the intake and the upper one is the exhaust. I just got to make sure that I didn't switch the labeling. The dimensions are correct. I just don't know if I made a mistake with the labels
 

JimP2014

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I don't know what happened to my last post but I can absolutely say the intake valve which is the bottom one. The maximum travel of the rocker arm tap that intersection is exactly 3 cm
 

JimP2014

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I'm not sure if this is always a rule but I believe when the Piston is at top dead center The rocker arms are exactly the same distance from the cylinder head plate and then it seems like the intake valve has a rocker arm that pushes the Piston rod out a little further than on the exhaust valve
 

JimP2014

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1000009856.jpg

I was able to crop the image and this would be the intake valve and it might be hard to see the number 3 cm but you can clearly see 4 cm. So that's how far away from the cylinder Head that the rocker arm travels so like I said it travels 3 cm away from the engine as measured from the flat plate which is part of the cylinder head
 

ILENGINE

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Went and measures the valve lift from the rocker arm back to the head on the valve side like you referenced in your example on an old engine. Not the same model number but would have the same camshaft. And I got around 1 CM of movement like you did.
 
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JimP2014

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IL engine thanks so much. So I haven't taken off the flywheel. But like I said I'm not a mechanic and I don't spend a lot of time with this us. Although over the course of say 50 years I have spent a lot of time on this but the only thing left is in your opinion and for now is it take off the flywheel. Just get another key and set everything back and make sure it's torqued to 80 ft lb and nothing is broken on the engine block from what I used this pry bar and all that stuff. Is that what you're concluding?


Thanks,

Jim
 

JimP2014

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IL engine thanks so much. So I haven't taken off the flywheel. But like I said I'm not a mechanic and I don't spend a lot of time with this us. Although over the course of say 50 years I have spent a lot of time on this but the only thing left is in your opinion and for now is it take off the flywheel. Just get another key and set everything back and make sure it's torqued to 80 ft lb and nothing is broken on the engine block from what I used this pry bar and all that stuff. Is that what you're concluding?


Thanks,

Jim
Actually before I do that so I mentioned above that when The rod for the intake travels back inside the engine. The distance to that plate is 2 cm. It only goes in as far as 2 cm. You're telling me yours travel s in to the 1 CM Mark. Where is mine does not. Do you think that's a problem?

Jim
 

JimP2014

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Actually before I do that so I mentioned above that when The rod for the intake travels back inside the engine. The distance to that plate is 2 cm. It only goes in as far as 2 cm. You're telling me yours travel s in to the 1 CM Mark. Where is mine does not. Do you think that's a problem?

Jim
Oh I think I see what you did. You measured the amount of movement the difference and you came up with 1 cm where I was giving absolute coordinates more or less. So yes they both travel about 1 cm just like yours travels about 1 cm. I think that's what you're saying now. I misread it
 

JimP2014

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Oh I think I see what you did. You measured the amount of movement the difference and you came up with 1 cm where I was giving absolute coordinates more or less. So yes they both travel about 1 cm just like yours travels about 1 cm. I think that's what you're saying now. I misread it
1000009858.jpg
 

JimP2014

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So obviously the flywheel key is sheered so there has to be reasons for that and it probably happened the very first time a few days ago after I put the flywheel back so it probably broke pretty quickly. So there has to be a reason for that. I'm going to say one reason might be I didn't torque it to at least 80 foot pounds. I just wonder before I get another flywheel key and put it back if there's anything else I should look for. I did see copper windings and that's the thing that goes around the flywheel so to speak. But it's part of the engine and I'm hoping that only is for charging the battery and nothing else. I don't know if any of those windings are broken because I don't look that closely but I will in a while. So what could be the possible causes of a sheered flywheel key?

Jim
 
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