How to Remove Piston from Cylinder

A member of our EAA chapter has a cylinder from a Franklin 150 engine
(off the engine.) The piston was pushed too far up and the top ring
sprung out so it now overlaps the cylinder sleeve which locks the piston
in place.

Does anyone have a technique to get the piston out? Preferably while
doing the least amount of damage. (So no explosives, please!)

Thanks,
Paul

Paul Dow (Remove Caps in mail address) wrote:
(So no explosives, please!)

Thanks,
Paul

How do expect any help if you tie our hands?

A member of our EAA chapter has a cylinder from a Franklin 150 engine
(off the engine.) The piston was pushed too far up and the top ring
sprung out so it now overlaps the cylinder sleeve which locks the piston
in place...

The last time I heard of that happening, the guy sawed the cylinder
head off the top of the cylinder with a bandsaw. In the process, he
zinged the piston pretty bad, pretty much ruining everything there.

My advice would be to see if there's a cylinder overhaul shop with the
capacity of unscrewing the head from the barrel. If so, send it to
them and see if they can rescue it. If not, make a lamp or bookend out
of it.

Thanks, Bob K.

"Bob Kuykendall" wrote in message
...
A member of our EAA chapter has a cylinder from a Franklin 150 engine
(off the engine.) The piston was pushed too far up and the top ring
sprung out so it now overlaps the cylinder sleeve which locks the piston
in place...

The last time I heard of that happening, the guy sawed the cylinder
head off the top of the cylinder with a bandsaw. In the process, he
zinged the piston pretty bad, pretty much ruining everything there.

My advice would be to see if there's a cylinder overhaul shop with the
capacity of unscrewing the head from the barrel. If so, send it to
them and see if they can rescue it. If not, make a lamp or bookend out
of it.

Thanks, Bob K.

That'd be my advice as well. I've watched as one of these shops mounted a
cylinder in their jig and very precisely and evenly heated the head until it
unscrewed. I was told they keep the aluminum head and replace the steel
barrel. I'd bet your friend won't be the first to show up with this
problem.

Thanks for the replies.

Unfortunately it looks like the head doesn't unscrew like a Lycoming or
Continental would. This is from a Franklin engine, so we believe it's a
single piece casting. I guess a cylinder shop could heat barrel to get
the steel sleeve out. Hopefully that will provide enough clearance to
get it out.

If not, I guess it gets turned into a tacky lamp. I could put it next to
the other lamp I won as a "Major Award".

Paul

Bill Daniels wrote:
"Bob Kuykendall" wrote in message
...
A member of our EAA chapter has a cylinder from a Franklin 150 engine
(off the engine.) The piston was pushed too far up and the top ring
sprung out so it now overlaps the cylinder sleeve which locks the piston
in place...
The last time I heard of that happening, the guy sawed the cylinder
head off the top of the cylinder with a bandsaw. In the process, he
zinged the piston pretty bad, pretty much ruining everything there.

My advice would be to see if there's a cylinder overhaul shop with the
capacity of unscrewing the head from the barrel. If so, send it to
them and see if they can rescue it. If not, make a lamp or bookend out
of it.

Thanks, Bob K.

That'd be my advice as well. I've watched as one of these shops mounted a
cylinder in their jig and very precisely and evenly heated the head until it
unscrewed. I was told they keep the aluminum head and replace the steel
barrel. I'd bet your friend won't be the first to show up with this
problem.

"Paul Dow (Remove Caps in mail address)" wrote in
message ...
A member of our EAA chapter has a cylinder from a Franklin 150 engine (off
the engine.) The piston was pushed too far up and the top ring sprung out
so it now overlaps the cylinder sleeve which locks the piston in place.

Does anyone have a technique to get the piston out? Preferably while doing
the least amount of damage. (So no explosives, please!)

Take an old spark plug and break out the ceramic center, then thread the
steel body for a zerk fitting. Be sure both valves are closed, hook up
grease gun and start pumping; you might be able to build enough pressure
(grease guns are cabable of several thousand psi) to break the ring and
force the piston out or even push the liner out of the one-piece
cylinder/head.

Does anyone have a technique to get the piston out? Preferably while doing
the least amount of damage. (So no explosives, please!)

Take an old spark plug and break out the ceramic center, then thread the
steel body for a zerk fitting. *Be sure both valves are closed, hook up
grease gun and start pumping; you might be able to build enough pressure
(grease guns are cabable of several thousand psi) to break the ring and
force the piston out or even push the liner out of the one-piece
cylinder/head.

Adding to that idea heat the whole thing in an oven and then pack the
bore with ice upon removal. Remove the piston and the steel liner as
one assembly. Then renew as one would normally with a Franklin
cylinder/head combo ????

Never had this problem, and never tried this fix .............. Pure
speculation on my part.
================
Leon McAtee
Will remember not to do the same with my Franklin :-)

On Oct 1, 11:29*am, "Paul Dow (Remove Caps in mail address)"
wrote:

Does anyone have a technique to get the piston out? Preferably while
doing the least amount of damage. (So no explosives, please!)
-------------------------------------------------------------------------------------------------

I don't see any easy-out for this one.

I assume you're willing to sacrifice the piston in order to salvage
the cylinder, in which case you might try soaking the piston with
liquid nitrogen or other cryogenic that should allow you to shatter
the piston along the ring-groove.

Depending on how much of the upper portion of the piston is obscured
by the wrist pin, you might consider fabricating a fixture of some
sort bearing a number of high-gauss rare-earth magnets, the idea being
to cause the ring to be drawn back into its groove whilst the assembly
is under tension.

In a similar vein, the suggestion about using the piston to remove the
cylinder liner would appear to have merit. You should be able to rig
the assembly so as to create considerable tension between the cylinder
and the piston. The manual should give you some idea as to the
required temperature difference, which would be obtained by raising
the whole assembly to a given temperature then hitting the piston AND
liner with liquid nitrogen.

-R.S.Hoover

wrote:
On Oct 1, 11:29 am, "Paul Dow (Remove Caps in mail address)"
wrote:

Does anyone have a technique to get the piston out? Preferably while
doing the least amount of damage. (So no explosives, please!)
-------------------------------------------------------------------------------------------------

I don't see any easy-out for this one.

I assume you're willing to sacrifice the piston in order to salvage
the cylinder, in which case you might try soaking the piston with
liquid nitrogen or other cryogenic that should allow you to shatter
the piston along the ring-groove.

Depending on how much of the upper portion of the piston is obscured
by the wrist pin, you might consider fabricating a fixture of some
sort bearing a number of high-gauss rare-earth magnets, the idea being
to cause the ring to be drawn back into its groove whilst the assembly
is under tension.

In a similar vein, the suggestion about using the piston to remove the
cylinder liner would appear to have merit. You should be able to rig
the assembly so as to create considerable tension between the cylinder
and the piston. The manual should give you some idea as to the
required temperature difference, which would be obtained by raising
the whole assembly to a given temperature then hitting the piston AND
liner with liquid nitrogen.

-R.S.Hoover


This idea is the best so far--I would recommend hanging the assy. by the
rod, and attaching heavy weight to cyl head.. Then apply heat to barrel
of Cylinder.

I keep some old Coleman thermos bottle liners (vacuum bottles) then go
out to propane storage tank, crack the liquid line ,and after the valve
& line has chilled, introduce liquid into vacuum bottle...Careful--
the temp is -42°C-(-62°F)AND of course the vapor is highly flammable,and
1.5 times as dense as air--so it settles in low places.

Extinguish all fires & pilot lights---WEAR GOGGLES---The liquid will
boil violently upon contact with the hot metal---You have to do this
when you live 50 miles from Mr.Linde--& he might not have any liquid N2
that day anyhow..
Jerry

On Oct 2, 9:41*am, Jerry Wass wrote:
wrote:
On Oct 1, 11:29 am, "Paul Dow (Remove Caps in mail address)"
wrote:

Does anyone have a technique to get the piston out? Preferably while
doing the least amount of damage. (So no explosives, please!)
---------------------------------------------------------------------------*----------------------

I don't see any easy-out for this one.

I assume you're willing to sacrifice the piston in order to salvage
the cylinder, in which case you might try soaking the piston with
liquid nitrogen or other cryogenic that should allow you to shatter
the piston along the ring-groove.

Depending on how much of the upper portion of the piston is obscured
by the wrist pin, you might consider fabricating a fixture of some
sort bearing a number of high-gauss rare-earth magnets, the idea being
to cause the ring to be drawn back into its groove whilst the assembly
is under tension.

In a similar vein, the suggestion about using the piston to remove the
cylinder liner would appear to have merit. *You should be able to rig
the assembly so as to create considerable tension between the cylinder
and the piston. *The manual should give you some idea as to the
required temperature difference, which would be obtained by raising
the whole assembly to a given temperature then hitting the piston AND
liner with liquid nitrogen.

-R.S.Hoover

This idea is the best so far--I would recommend hanging the assy. by the
rod, and attaching heavy weight to cyl head.. Then apply heat to barrel
of Cylinder.

I keep some old Coleman thermos bottle liners (vacuum bottles) then go
out to propane storage tank, crack the liquid line ,and after the valve
& line has chilled, introduce *liquid into vacuum bottle...Careful--
the temp is -42°C-(-62°F)AND of course the vapor is highly flammable,and
1.5 times as dense as air--so it settles in low places.

Extinguish all fires & pilot lights---WEAR GOGGLES---The liquid will
boil violently upon contact with the hot metal---You have to do this
when you live 50 miles from Mr.Linde--& he might not have any liquid N2
that day anyhow..
Jerry- Hide quoted text -

- Show quoted text -
Is there any reason why the pistons head can’t be drilled out and an
insert fabricated to slip inside it through the top for use as a
puller? You can use a chemical fire extinguisher to super cool the
cylinder head for shrinkage and then follow up with a series of sharp
pulls to extract the piston. If the piston shatters then remove it,
or its top pulls loose than fabricated another top insert to friction
fit inside the piston walls and try the whole chill/pull process
again. Of course this is just my .02 worth folks along with the
admonition that I’m more of a parts changer than mechanic.
Joe Stevenson