# How to get piston and ring back in cylinder



## GlynnC (May 9, 2009)

How do you guys get a piston with rings back in a cylinder. I've had moderate success using fingers and screwdrivers but looking for some suggestions.

My grandson (11 years old) and I (much older) have torn down a trimmer engine just for the learning experience for him. It was a running motor that I picked up for $1.00--Solo brand. We're talking about the function of the parts and how a 2-cycle engine works. We will put it back together and hope to get it to run again. It would be very difficult, if not impossible, to find a replacement ring, so I'm hoping we don't break it. 

How's the best way to get the piston back in the cylinder? I have compression sleeves for bigger engines, but nothing this small. I work on a lot of trimmers, but seldom pull the piston with the intent to put it back together.

Thanks for your help.
Glynn


----------



## John Lolli (Nov 3, 2005)

How about a hose clamp.


----------



## chuck_thehammer (Oct 24, 2007)

get a heater hose clamp...screw type...sand the inside with 600 grit paper ...

better way...go to a motorcycle shop and order a piston ring compression tool...for 50cc or so...looks like a pair of plyers with 2 semicircle on the ends...
I own several.


----------



## usmcgrunt (Sep 16, 2007)

All the cheap two cycles I've worked on had removable cylinders and the piston came out the bottom.The cylinders have a taper on the bottom and with a little oil on the piston and ring,using one finger as a compressor,they slid right in with no damage or cussing.Removing a ring without breaking it from a scored on carboned piston is the hard part.If replacing the piston,the ring gap side with the pin faces the exhaust port.Just my opinion,hope this helps.


----------



## duffer72 (Jul 23, 2011)

Agree with Grunt, oil it up, the cly is tapered in 99% of the time, it should go in fairly easy using just your fingers, I my self wouldn't use a clamp or screw driver as both may damage the ring surface, just make sure the gap in the rings stay located on the pin, otherwise they will spin on the piston and get caught on one of the ports


----------



## GlynnC (May 9, 2009)

Thanks guys for your answers. This is a trimmer engine with piston coming out (and going back in) the bottom of the cylinder. I know the risk of removing the ring and putting it back on so we are not going to do that. This is a very clean engine, with apparent very little run time, but we are just doing this as a learning project for my grandson (and maybe a little for me also). The fun part will be getting it to run again.

Just for fun, I'll make a final post after we have it back together. I'm really proud of this little guy--he's been starting and running blowers and trimmers for several years (remember he's only 11), and can operate my 61" Scag zero turn as good as I can.


----------



## usmcgrunt (Sep 16, 2007)

GlynnC,I think it's great that your taking your knowledge and his enthusiasm to save machines that would normally be thrown away when they stop working.The satisfaction of saying "I fixed that" is priceless.Even if his career path turns out to be a brain surgeon,he will always remember that Grandpa taught him how to fix things.Good for you!:thumbsup:


----------



## billsmowers (Mar 21, 2008)

usmcgrunt said:


> all the cheap two cycles i've worked on had removable cylinders and the piston came out the bottom.the cylinders have a taper on the bottom and with a little oil on the piston and ring,using one finger as a compressor,they slid right in with no damage or cussing.removing a ring without breaking it from a scored on carboned piston is the hard part.if replacing the piston,the ring gap side with the pin faces the exhaust port.just my opinion,hope this helps.


ring gap side with pin faces exhaust ? Are you shore as it would catch the port sounds like piston fitted backwards arrow points to exhaust no ring gap on that side of the piston

bill


----------



## duffer72 (Jul 23, 2011)

You are correct arrow towards exhaust port


----------



## usmcgrunt (Sep 16, 2007)

I apologize and stand corrected!


----------



## buy*david (Nov 7, 2011)

*rings*

The only thing that should stop you from getting it to slide into the cyl is not having the ring pin lined up. On two cycles there is a alignment pin in the ring land to keep the ring from turning in the land unlike four cycles. Make sure that this small pin is lined up with the ring end gap before installing and that it stays lined up while installing. Doing this and oil and fingers will do it easily.


----------



## GlynnC (May 9, 2009)

Again thanks guys for your help--tomorrow afternoon is another "small engine clinic" time with my grandson. He's really interested in this, and this makes his "pawpaw" really interested also. One of the fun things about being a grandparent is making special memories with the grandkids!


----------



## buy*david (Nov 7, 2011)

*splitter*

I have a Ryobi electric log splitter and it is very loud. Does anyone know if this is normal. Model # RY49701


----------



## usmcgrunt (Sep 16, 2007)

buy*david said:


> I have a Ryobi electric log splitter and it is very loud. Does anyone know if this is normal. Model # RY49701


I have never used one of these,so I don't know how loud they are supposed to be.Hydraulic equipment will get louder if the oil level is low or there is air in the system and needs to be bled out.You will get more opinions if you start a new thread with your problem.No one will see your request buried in a two cycle cylinder question.Hope this helps.


----------



## buy*david (Nov 7, 2011)

*Thanks Grunt*

Hey Grunt, I did post it in general but no response either. The good news is I tore it down and found a bad bearing. $13 and it's running good and quite. Thanks for the help.


----------



## GlynnC (May 9, 2009)

Well, getting the piston and ring back in the cylinder was easy--squeezed the ring in tight with fingers, making sure gap was ligned up on pin, wiggled it a little while pushing, and in it slipped. I was able to turn the piston and view the ring position on the pin thru the intake--ring was seated properly around the pin.

Tomorrow we put the coil back in, install carb and fuel lines, and hopefully give it pull to see if it runs.

Still having fun with grandson!!!!


----------



## GlynnC (May 9, 2009)

It's back together---------------and it runs!!! The only real problem we had was with the gas lines, and we were able to get them attached correctly. Primer was broken and I forgot to take a new one with me so we shot a little fluid in the sparkplug hole and she fired up and ran. He thought the "business card feeler guage" was a neet way to set the coil gap, then we found a real feeler guage in his dad's tool box--it was set right at .010.

Big smile on grandson's face (and on Pawpaw's). He's wanting to find a way to put it on a foot scooter--that would just be too cool!!!!


----------



## 30yearTech (Sep 14, 2006)

That's Great!!

Glad to hear you all are having so much fun!

:thumbsup::thumbsup::thumbsup::thumbsup:


----------



## usmcgrunt (Sep 16, 2007)

Good job Pawpaw,the memories and skills are starting to add up.


----------



## geogrubb (Jul 28, 2006)

GlynnC;
You are having an adventure many grandfathers would love to have, and you and the grandson will have a memory that can never be take away. Have a good one. Geo


----------

