B&S 19.5 compression/ camshaft issue

Laneman

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My camshaft compression release gave out. Too much compression. Learned on youtube how to start it by holding hand over intake, which does work to get it started. Is there a workaround other than this to avoid camshaft replacement? I have read that new camshafts fail not long after replacement. Looking for a permanent solution.
 

StarTech

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For permanent solution buy a Kawasaki or Kohler engine that have a more robust system. Other than that the Briggs camshaft two at a time but these are not failing as bad as some would lead you to believe. It just appears that they failing more often due to the shear number of these engines. But by all means avoid the after market Chinese camshafts they are not made to specs.
 

Laneman

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I'd like to add a manual compression release like I have on my Husqvarna chainsaw and bypass the Cam mounted ACR altogether
 

StarTech

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You can try that if you wish to be getting on and off the mower everytime you want to start the engine. And if fails to start get back off again and again; unless, you someone that willing to just stand around to depress the decompression everytime.
 

Rivets

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Have you checked with the repair shops in your area. They might just have a scrap engine laying around that you can scavenge a cam out of. May be the cheapest remedy and job done right.
 

bertsmobile1

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I'd like to add a manual compression release like I have on my Husqvarna chainsaw and bypass the Cam mounted ACR altogether
It will work sort of.
Most times it will not turn off by itself
It was a common trick with dirt bikes that had no kick starter running on high compression dope engines back in the 80's before rollers became available at a reasonable price .
 

Daddio7

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On mine I would just open the hood and muscle the engine past the compression stroke then hop back on the seat and start it. I did disable the seat switch so I could get off without have to go through that again. Did that for 10 years. I am 70, last year I got a new mower, my third ever, JD 130E. I have lived on the same property for fifty years and yes, I am cheap.
 

SamB

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My camshaft compression release gave out. Too much compression. Learned on youtube how to start it by holding hand over intake, which does work to get it started. Is there a workaround other than this to avoid camshaft replacement? I have read that new camshafts fail not long after replacement. Looking for a permanent solution.
I used that "covering the intake' hack,until I bought a new engine. However, as was pointed out here, there are broken pieces inside the engine that may not play nice with other parts in there. There are many 31R Briggs engines out there that have failed for different reasons besides the compression release breaking. I don't know enough about the differences of the cams from 17hp 17.5hp and 18 and 19hp,so those cams may not interchange from one hp to another.
 

Laneman

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Thanks for the replies and ideas. I watched a cam replacement video and the oil sump did not look very deep, meaning the broken pieces could get into some moving parts. Think I'll just get the OEM camshaft and do it right. I just bought the mower for $200 as a no start. It's a 46 inch Craftsman in good shape, maybe worth the price of a new cam.
 

StarTech

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I used that "covering the intake' hack,until I bought a new engine. However, as was pointed out here, there are broken pieces inside the engine that may not play nice with other parts in there. There are many 31R Briggs engines out there that have failed for different reasons besides the compression release breaking. I don't know enough about the differences of the cams from 17hp 17.5hp and 18 and 19hp,so those cams may not interchange from one hp to another.
All of the 210000, 280000, 310000, and 330000 series OHV engines use the same camshaft but for some reason the 310000 and 330000 are the engines that these are constantly failing on . Now take that with a grain of salt as these are also the most installed Briggs single cylinder rider engines so the volume of them out there is huge. The 793880 (superseded to 84005207) is definitely a weak point of these engine along with the head gaskets. Since the OP has a 310000 series I highly recommend changing the head gasket too while he/she is replacing the camshaft.
 
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