Engine stops cranking when it hits compression stroke

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Dave9354

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  • / Engine stops cranking when it hits compression stroke
Have riding lawn tractor with B&S engine model # JBSXS 5402vl. Full charged battery and new starter. So when it cranks over it stops spinning when it gets to compression stroke. Sometimes it will fire up before it stops spinning and it will run great. Any help would be appreciated. when I remove the spark plug it spins the the engine with no problem. I have to keep spinning the flywheel back by hand. What could be the problem? Thanks, Dave.
 
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ILENGINE

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  • / Engine stops cranking when it hits compression stroke
That is not the engine model number. The engine model most likely is stamped into the valve cover Should say model, type and code above the information. And if this is a single cylinder Intek engine then one or both of the following has happened. the valves are out of adjustment preventing the compression release from working or the compression release mechanism on the camshaft is broken and will require replacement.
 
Tiger Small Engine

Tiger Small Engine

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  • / Engine stops cranking when it hits compression stroke
ILENGINE said:
That is not the engine model number. The engine model most likely is stamped into the valve cover Should say model, type and code above the information. And if this is a single cylinder Intek engine then one or both of the following has happened. the valves are out of adjustment preventing the compression release from working or the compression release mechanism on the camshaft is broken and will require replacement.
Click to expand...
Other possibilities:

Battery is weak and on the way out.
Voltage drop due to corrosion and bad electrical connections.
Starter is borderline and on the way out.
 
StarTech

StarTech

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  • / Engine stops cranking when it hits compression stroke
Or it could like the JD E110 here. Boy what a mess to clean up. At least two other techs have been working on the engine and gave up. And btw the last tech both my shop was a JD tech.

It is actually destroying the starter Bendix from kicking back so hard. Here is what I have found on it so far.
  • Of course the starter Bendix is destroyed.
  • Pulled the rocker (which just fell off as someone already had it off) and found the EX at over .055" and the IN over .020.
  • Adjusted the rockers to spec to only find no ACR bump.
  • And of course the new battery is now needing a recharge because someone left the keyswitch on.
Now of course I got pull the engine and replace the camshaft and the complete starter Bendix on the brand new starter. I got the parts in stock so it just getting to the project. Just hoping no other damage from the broken ACR as it can take out the governor among other things.
 
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Dave9354

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  • / Engine stops cranking when it hits compression stroke
Thanks guys! I will be checking the valves to see if they need adjusting.
 
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