Pull all of the plugs and look at them closely for even a slight difference.
Pull all of the plugs and look at them closely for even a slight difference.
Pull all of the plugs and look at them closely for even a slight difference.
I typed this thrice as it cannot be overstated.
You can often read a spark plug like a book to find an issue with an engine.
The one plug which looks different will likely be from the cylinder which has an issue.
To determine if a valve isn't seating tightly in that cylinder, put that piston at top dead center. If you have the type of compression gauge which has a quick disconnect, you can separate the hose from the gauge and add shop air to the male quick connect fitting. It should fit your shop air hose.
Leave the truck in gear to keep the piston from moving down from the air pressure. Listen for air escaping through the carburetor or the exhaust. Fold and pinch the air hose to reduce the air pressure from your compressor. Too much pressure will force air past the rings and give you a false reading.
Carl
Last edited by 52Carl; 04/29/2019 1:49 AM.
