112 johnson zero compression in 4th cylinder

[flatsman77]

I messed up and ran my 112 johnson super lean (almost no oil mixed). Compression on 1-3 is 129#, 124# and 125# respectively. Number 4 is zero. Tried WD 40 and then a bit of 2 stroke oil. Still zero.<br /><br />Is it too late to try decarb stuff? What does an overhaul of one cylinder cost on average?

 

[rickdb1boat]

Re: 112 johnson zero compression in 4th cylinder

It's too late and it depends on the extent of the damage that has occured. It will have to be torn down to see what is salvagable and what is not.

 

[Solittle]

Re: 112 johnson zero compression in 4th cylinder

Pull the head on that side & post back with your findings. We can go from there.