Compression Lock

Archer03

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I have a B&S 33S877-0013 engine in a Husqvarna CTH2138HR ride on. Won't crank. Checked all electrics-fine. Removed spark plug and engine cranks normally. Adjusted valves 6 times and still no joy. As soon as spark is in engine wont crank. Valve springs appear OK - without removing them.
Any suggestions what to do next?

Thanks
 

bertsmobile1

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turn the engine over by hand watching the inlet valve
You should see it close then open a touch then close again before the piston gets to TDC
If this does not happen try dropping the inlet valve lash down to 0.003"
If it still does not happen then the cam lobe is worn or the ACR mechanism has fallen apart .
Only solution is replacing the cam shaft.
Not a difficult job but requires the engine to be pulled and getting the engine pulley off can be somewhat of a challenge.
 

Scrubcadet10

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Saw the Camshaft PN, 793880, isn't that the cam Briggs had troubles with cam lobe wear?
Jack's shows it superseded to 84005207
 

Archer03

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That's interesting. I can't locate 84005207 in Australia. If it is superior to 793880 I may have to bring it in from the US. Can anyone confirm it is a superior replacement?
 

ILENGINE

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Bert it looks like Briggs is playing around with ;part numbers again. Supercedes from the 793880 with a special note that it doesn't contain tappets.
 

StarTech

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Yes they just recently did that (793880 to 84005207) just another way to increase the pricing behind our backs. Sorta the cylinder kit I ordered last year where it is was to be both heads for $145 then when I finally got the head I needs it just one head @ $145. The customer canceled the repair job once they found out that they were only getting one cylinder head so I got stuck with the head.

As long as you can still get the 793880 get it as that what I did here as these are always breaking the ACR.
 

Tinkerer200

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Yes they just recently did that (793880 to 84005207) just another way to increase the pricing behind our backs. Sorta the cylinder kit I ordered last year where it is was to be both heads for $145 then when I finally got the head I needs it just one head @ $145. The customer canceled the repair job once they found out that they were only getting one cylinder head so I got stuck with the head.

As long as you can still get the 793880 get it as that what I did here as these are always breaking the ACR.
Main reason for replacing heads is slipped valve guides which can be permanently fixed fairly easily and inexpensively.
Walt Conner
 
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