Re: 140 mercruiser engine tap
I am not sure of the procedure to adjust lash, but I can tell you that the wrist pin is the large pin that holds the piston to the connecting rod. If that is the culprit you will most likely have to pull the motor out to remove the connecting rod and piston from the crank. There is no tightening that pin. All you can do it look at why it is making noise. If it is loose then you will probably need to replace that piston or rod. Then you start to look at why replace one piston when there are 3 others that you have easy access to right now. Then you look at the bores and figure why not hone them. Then the machine shop tells you they are too far out of spec and you will have to bore them. It seems to go on and on. That is a real job, but I would never go so far as to discourage you from giving it a try if you are willing to put in the time and money. It is far easier to buy a short block already rebuilt though.
Some people don't even want to change their own bellows let alone tear in to the actual motor. It is all a matter of what you want to learn by just doing it. It gets expensive, but no amount of asking questions from people that tell you to read a manual will teach you more then taking it apart and looking at how it goes back together.
I will hypocritically tell you to download or buy the proper manual and read up as much as possible. Then ask questions about what the manual it telling you to do. I can tell you first hand that there is no way a novice is going to read the Mercruiser Factory Manual and figure out half of what it is telling you to do. I seem to spend half my time trying to figure out where o-rings and gaskets actually go and I consider myself mechanically inclined.
I am not sure of the procedure to adjust lash, but I can tell you that the wrist pin is the large pin that holds the piston to the connecting rod. If that is the culprit you will most likely have to pull the motor out to remove the connecting rod and piston from the crank. There is no tightening that pin. All you can do it look at why it is making noise. If it is loose then you will probably need to replace that piston or rod. Then you start to look at why replace one piston when there are 3 others that you have easy access to right now. Then you look at the bores and figure why not hone them. Then the machine shop tells you they are too far out of spec and you will have to bore them. It seems to go on and on. That is a real job, but I would never go so far as to discourage you from giving it a try if you are willing to put in the time and money. It is far easier to buy a short block already rebuilt though.
Some people don't even want to change their own bellows let alone tear in to the actual motor. It is all a matter of what you want to learn by just doing it. It gets expensive, but no amount of asking questions from people that tell you to read a manual will teach you more then taking it apart and looking at how it goes back together.
I will hypocritically tell you to download or buy the proper manual and read up as much as possible. Then ask questions about what the manual it telling you to do. I can tell you first hand that there is no way a novice is going to read the Mercruiser Factory Manual and figure out half of what it is telling you to do. I seem to spend half my time trying to figure out where o-rings and gaskets actually go and I consider myself mechanically inclined.
