How to Install Piston Rings on a Four Stroke Piston.
Introduction: How to Install Piston Rings on a Four Stroke Piston.
Hello. My name is <PERSON>. I am currently studying mechanical engineering in Technological University of Shannon in Athlone. In this instruction, you will find how to correctly remove and install piston rings on a four stroke piston.
Supplies
For this task you will need:
-Piston ring pliers.
-A new set of rings (IF applicable.)
A piston ring pliers is not a requirement although it is recommened to prevent breaking piston rings with your hands. In this document I will only be using piston ring pliers.
Step 1: Understanding Different Rings
In front of you, will be a piston with the piston rings installed. In the picture above, you can see a total of five rings inside the piston grooves.
(First two grooves.)
First ring from the top: Compression Ring one.
Second ring from the top: Compression Ring two.
(Last groove.)
Top ring: Oil control ring.
Middle ring: Oil expander ring. (spring like shape)
Bottom ring: Oil control ring.
Step 2: Using the Piston Ring Pliers
The pliers are used expand the rings to allow the rings to clear the piston and be seated comfortably in the grooves.
Note: The pliers will only be used for the two compression rings as the oils rings are to small to be removed with the pliers.
In the picture above is the correct side up of the pliers. At the top of the pliers is where the piston ring gaps will be seated in to allow the pliers to expand the rings.
CAUTION! Do NOT expand the rings much more than the diameter of the piston. If expanded too much, the ring will snap and or create perminent damage that will reduce performance of your engine.
Step 3: Remove the Top Compression Ring
* Place the gap of the top compression inside the front of the pliers.
* You may need to push out the ring gap out from the groove to give the pliers space to grip the ring.
* Squeeze the pliers until the ring expands enough to clear the piston. Lift the ring up from the top of the piston and place it on a surface beside you.
Step 4: Remove the Second Compression Ring
This step is similar to step 3. 751
The only difference is that the second compression ring is in the second groove in the piston. Take extra caution taking the ring out to avoid the ring slipping out of the pliers and entering the top groove.
You now have a piston that has both compression rings removed.
Step 5: Identifying the Oil Rings
In the picture presented above, there is a total of three rings inside groove three. These are the oil rings.
The top and bottom rings are much more skinnier and flexible than the compression rings. Because they are skinny the pliers will not catch the gaps. Removing them you will need to use your fingers.
The middle ring is the oil expander ring. It is a spring like ring and is the easiest ring to install/remove.
Step 6: Remove the Top and Bottom Oil Control Rings
Removing the oil rings is the most difficult task endured in the process.
* Indentify the top ring of the three pairing. Find the gap of the oil control ring.
* Catch the gap of the ring with your index finger nail and slowly begin expanding the ring.
* Lift the one part of the gap up and place it on top of the piston like in the picture provided.
* Then, roll out the ring from the gap until the ring is free from the groove.
Repeat the same process with the bottom oil control ring.
Step 7: Remove the Oil Expander Ring
Upon removing the oil control rings there will be a oil expander ring left to remove. This ring is reasonably flexible and is easy to remove.
* Locate the split in the expander ring. In the picture above is how the ring shall look inside of the piston groove three.
* Catch your index finger nail in the split or beside it and expand it. You will find that the ring expands easily.
* Roll the ring out just like the oil control rings.
Step 8: Preparing to Install the New Piston Rings
Upon removing the rings, you will have a naked piston infront of you. Installing rings is the same as removing only adding in a few extra details to ensure that your engine will run as intended.
Make sure you prepare the piston for new rings by cleaning out the gaps with compressed air or blowing out the gaps with your mouth.
Always check the piston ring manufacturer's manual as there may be some extra details not covered here. 751