Reply To: Backfire/misfire thru carb

[Don]

Oh boy, you have got quite the set up there. Not OMC’s finest hour for sure. So, how did you mount the older 140hp in that cave? Or, did you just put the older 140hp powerhead onto the existing set up? Some pictures would help us understand just what you have/set up.
Try loosening the screw to the roller, and move it away/off the cam at dead idle speed just to see if that makes any difference. Try to take a picture of the linkage before you make any changes, I realize it is tough to get down in there though….Take pictures of the black sealer you mentioned also.
So, you have never had this engine running before, so we really don’t know what we have here. Try to do a compression test as well..