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14hp briggs vanguards v twin, only 1 cylinder has compression

#1

A

ACDC

i have a stiga project with a briggs v twin. one cylinder has compression and the other one does not. the spark plug from the cylinder with compression is black and looks well used. however, the spark plug without compression looks like it has never been used.

i got this mower for free as a project and i dont want to spend a lot of money on this but its evolving into a bank account every time i see it. what could be wrong with it.


#2

I

ILENGINE

Either a bad valve or broken rod. From the description of the plug I would lean toward broken rod. on that cylinder


#3

pugaltitude

pugaltitude

How do you know its got bad compression?


#4

A

ACDC

im going to take it a part today. so i will look and see weather it is worth repairing. i know it has got bad compression on that cylinder as i done a compression test and got 000 psi on that cylinder but on the other cylinder i had strong compression.


#5

reynoldston

reynoldston

Have you done a simple thing like remove the valve cover? Maybe just a push rod came out of place


#6

A

ACDC

i took it apart today and it has a worn piston ring and it has so many tiny bits of metal all over everything in the engine. the bore was full of flakes and bits of carbon and the piston has a lot of carbon on it.

also the exhaust valve that is turned by the cams inside the engine was jammed closed. with is another reson for the compression loss


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