piston ring fitting
Discussion
I am about to start fitting my new piston rings to my rover v8 4.6 this weekend. How do you get the oil ring on is there a special tool. I have bought a set of pliers for the top ring and second, they might be cr@p though as they only just about grip the ring. But these wont grip the oil ring. How do I do it?? Dont want to f
k up my new rings. And the oil ring has one ring above the the wavy ring (so technical..lol) then another below do they have a right and wrong way to be fitted.
Thanks
Neal
i normaly fit oil rings from the bottom of the piston up they should open up just enough to slide them up the piston, start with the thin ring first slide up the piston and let it slip into the grove, then slide up the wavey ring slide that into the grove under the thin ring you slid up first, then slide up the second thin ring and make sure it slips into the grove under the wavey ring, so now it should look like ring, under that one the wavey ring, and then under the wavey ring should be the other ring,
then fit your piston rings make sure you get them the right way up copy like for like fit the lowest one first this time start at the top of the piston and slide them down into the groove, then you want to rotate the rings so the gaps in the rings are facing away from each other, also i found to not to line the gaps in the rings above the gudgon pin as some times oil/compression can squeeze pass.
another tip is to use an old piston ring to clean out the grooves in the pistons and if its got small holes in the groove where the oil ring sits use a small drill bit to clean them out,
then fit your piston rings make sure you get them the right way up copy like for like fit the lowest one first this time start at the top of the piston and slide them down into the groove, then you want to rotate the rings so the gaps in the rings are facing away from each other, also i found to not to line the gaps in the rings above the gudgon pin as some times oil/compression can squeeze pass.
another tip is to use an old piston ring to clean out the grooves in the pistons and if its got small holes in the groove where the oil ring sits use a small drill bit to clean them out,
Dont position the top and second ring gaps on the thrust side of the piston,i have always fitted rings by hand as Tr7V8 says and have never broke one in 22 years of the motor trade,never expand the ring more than neccesary,some oil control rings can be wound spiral round the piston and either side of the serrated spacer(not for the top 2 though)
position the oil control pack end at 120 degree intervals.
position the oil control pack end at 120 degree intervals.Edited by That Daddy on Thursday 22 January 21:31
I've always fitted car ones by hand without any breakages, though I personally wouldn't slide the oil ring up the skirt simply due to the increased risk of gouging the piston with the ring ends. The three piece oil rings are dead easy to fit as they are so flexible. The cast ones are much stiffer, and easier to break.
My mate seems to use feeler gauges, but I was told years ago to cover the grooves with selotape so the rings slip over and clean off with thinners afterwards.

Bend both edges of the expander tab so that they still mate nicely, fit the 3 pieces one by one starting at the bottom, with 90deg separation of gaps. Just do a 180 sep for the top rings (they should all spin anyway ~ its just an initial positioning).
I don't twist the rings when fitting, I was told its really bad to 'spiral' when fitting rings but to keep them square, as any twisting is not good for the ring.
Ring markings vary ask the supplier if they are not obvious, you may well wonder why you asked if you view with a magnifying glass
How much do you want to go town on fitting them? or is it just a throw it together with new generic bits? The more you see about this subject the more you realize folks have different ways of doing it, some of us may use old fashioned methods that are not required by modern materials - we just know it works so keep doing it

Bend both edges of the expander tab so that they still mate nicely, fit the 3 pieces one by one starting at the bottom, with 90deg separation of gaps. Just do a 180 sep for the top rings (they should all spin anyway ~ its just an initial positioning).
I don't twist the rings when fitting, I was told its really bad to 'spiral' when fitting rings but to keep them square, as any twisting is not good for the ring.
Ring markings vary ask the supplier if they are not obvious, you may well wonder why you asked if you view with a magnifying glass

How much do you want to go town on fitting them? or is it just a throw it together with new generic bits? The more you see about this subject the more you realize folks have different ways of doing it, some of us may use old fashioned methods that are not required by modern materials - we just know it works so keep doing it

Mr2Mike said:
I've always fitted car ones by hand without any breakages, though I personally wouldn't slide the oil ring up the skirt simply due to the increased risk of gouging the piston with the ring ends. The three piece oil rings are dead easy to fit as they are so flexible. The cast ones are much stiffer, and easier to break.
thou you make a valid point i've found it easier to slide the oil control rigs up from the bottom to stop them catching on the other ring lands and twist the new ring you just keep them nice and straight and you shouldn't get any probs, the oil ring are not that tight so theres not much chance of them gouging the side of the piston you would have to apply some tight pressure to do this, pistons are quite tough and its usually good practice to rub over them with a fine emery paper to remove any shape edges,different courses for different hourses

Edited by skid-mark on Thursday 22 January 23:35
Tricky one this
First fit the oil ring expander, wavy thing into the groove. Next slip the upper and lower oil rings into place over the expander. That's easy as they are really slack, do it by hand. For the second ring, use a tool to hold the ends apart and carefully lower it down the piston from the top. If you haven't got an expander use feeler guages and rotate them behind the ring as you lower the ring or carefully spiral it down by hand, making sure the ends don't scratch the piston. I smooth the ends/corners with a file and emery cloth. Fit the top piston the same way. Be patient! Look for any marks indicating top side up or copy the old rings. Lastly, make sure the top two rings are free to rotate in their grooves, if they jam then smooth off the ends.
When you insert the pistons into the bores be very patient, if they won't go don't force them in, take a break or buy a better tool! I've f
ked up a few in my time! Best tools are Moroso or arp piston insertion tools. Easy to use and an absolute doddle!

First fit the oil ring expander, wavy thing into the groove. Next slip the upper and lower oil rings into place over the expander. That's easy as they are really slack, do it by hand. For the second ring, use a tool to hold the ends apart and carefully lower it down the piston from the top. If you haven't got an expander use feeler guages and rotate them behind the ring as you lower the ring or carefully spiral it down by hand, making sure the ends don't scratch the piston. I smooth the ends/corners with a file and emery cloth. Fit the top piston the same way. Be patient! Look for any marks indicating top side up or copy the old rings. Lastly, make sure the top two rings are free to rotate in their grooves, if they jam then smooth off the ends.
When you insert the pistons into the bores be very patient, if they won't go don't force them in, take a break or buy a better tool! I've f
ked up a few in my time! Best tools are Moroso or arp piston insertion tools. Easy to use and an absolute doddle!skid-mark said:
Mr2Mike said:
I've always fitted car ones by hand without any breakages, though I personally wouldn't slide the oil ring up the skirt simply due to the increased risk of gouging the piston with the ring ends. The three piece oil rings are dead easy to fit as they are so flexible. The cast ones are much stiffer, and easier to break.
thou you make a valid point i've found it easier to slide the oil control rigs up from the bottom to stop them catching on the other ring lands and twist the new ring you just keep them nice and straight and you shouldn't get any probs, the oil ring are not that tight so theres not much chance of them gouging the side of the piston you would have to apply some tight pressure to do this, pistons are quite tough and its usually good practice to rub over them with a fine emery paper to remove any shape edges,different courses for different hourses

Edited by skid-mark on Thursday 22 January 23:35
That Daddy said:
stevieturbo said:
Oil control rings are a doddle as everyone says.
For top two 1 piece rings...piston ring pliers are very cheap, and very worthwhile.
I would agree with the above if your not confident in using the finger method For top two 1 piece rings...piston ring pliers are very cheap, and very worthwhile.
stevieturbo said:
That Daddy said:
stevieturbo said:
Oil control rings are a doddle as everyone says.
For top two 1 piece rings...piston ring pliers are very cheap, and very worthwhile.
I would agree with the above if your not confident in using the finger method For top two 1 piece rings...piston ring pliers are very cheap, and very worthwhile.
you aint seen the skin thickness on my thumbs too many years of the motor trade 
Gassing Station | Engines & Drivetrain | Top of Page | What's New | My Stuff





