RunRyder RC
 6  Topic Subscribe
WATCH
 1 page 2750 views POST REPLY
HelicopterEngines Plugs Mufflers Fuel › Os 50 H - Piston Liner sleeve - Reuse or not?
08-03-2009 10:07 AM  8 years agoPost 1
itsjojo

rrKey Veteran

North East Pennnsylvania

My Posts: All  Forum  Topic

Yesterday my Os 50 Hyper went lean and popped with a flame out. I am experienced with having a few rebuilds under my belt from learning the tuning of this motor. I am troubleshooting the "cause" but my questions is can I reuse a marginal condition sleeve.

The sleeve is visually scored from the damaged ring-land being chipped off and the pinhole in the piston.

After cleaning the sleeve I can't feel any scoring with my finger and can't feel any when I dig my fingernail into the visual scoring on the inside of the liner. Other than this very light scoring there seems to be nothing wrong with the liner.

Is this reusable?

Thanks for any help
Jojo

JoJo
Foreseeing My Flybarless Future!

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
08-03-2009 01:53 PM  8 years agoPost 2
REGULATER

rrApprentice

Bakersfeild, CA

My Posts: All  Forum  Topic

If you wan't your motor to make good power like it did when it was brand new you need to change the sleeve. But you need think about buying a new motor because by the time you buy a piston ,liner,ring, and a sleeve your not far from a new motor.

Good luck

REGULTER

PM  EMAIL  GALLERY  Attn:RR  Quote
08-15-2009 12:43 AM  8 years agoPost 3
itsjojo

rrKey Veteran

North East Pennnsylvania

My Posts: All  Forum  Topic

yes. I reused the sleve and all is well. No power loss or any other problems. Been running it for a while now and it seems to be fine.

JoJo
Foreseeing My Flybarless Future!

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
08-15-2009 01:33 AM  8 years agoPost 4
wthford

rrVeteran

Monticello, Illinois

My Posts: All  Forum  Topic

The only reason to change it really is if there were measureable wear in it. Many times all you need is a new ring.

How can I soar with the Eagles when I work with turkeys??

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
08-15-2009 04:35 AM  8 years agoPost 5
dkshema

rrMaster

Cedar Rapids, IA

My Posts: All  Forum  Topic

Get hold of a brake cylinder hone...

chuck it up in a hand-drill, insert it into the cylinder, and while running the drill, move the hone in and out of the cylinder. It will remove the glaze from the cylinder walls and will restore the original cross-hatch (criss-cross) pattern to the walls. Clean the cylinder afterwards, then inspect.

You should do the above whenever you replace the piston ring, as it gives the new ring a change to seat properly as you go through the break-in process all over again.

From the sound of it, your cylinder is in good shape and there should be no reason you can't reuse it.

-----
Dave

* Making the World Better -- One Helicopter at a time! *

Team Heliproz

PM  EMAIL  GALLERY  Attn:RR  Quote
08-15-2009 05:42 PM  8 years agoPost 6
KevinB

rrKey Veteran

Saskatoon, Saskatchewan, Canada

My Posts: All  Forum  Topic

+1 for Dave's reply. The last hyper I rebuilt I didn't have any scores you could feel in the liner. I used the brake cylinder hone and just replaced the ring and bearings. Worked like new.

The big thing is to make sure you are moving up and down the cylinder any time the hone is rotating...and it should be turning slowly. Use some oil as well. The idea is to get the cross-hatching looking like original or at about 20-30 degrees off of level with the top of the piston. It doesn't take much time to do either so do a little and check often. Whenever you insert/remove the hone into/out of the cylinder, take the pressure off the grinding pads....don't just force it in or drag it out. Otherwise you'll be messing up your nice cross-hatching with vertical drag marks.

KevinB

PM  EMAIL  GALLERY  Attn:RR  Quote
08-16-2009 07:04 PM  8 years agoPost 7
wthford

rrVeteran

Monticello, Illinois

My Posts: All  Forum  Topic

To add to this, a few passes is all it takes. Just enough to actually see the cross hatching and your done. Compress the stones so they don't touch the walls when done and remove carefully so as not to drag vertical scratches. All you want is a scuff up, not remove any appreciable material. Otherwise, you'll ruin the cylinder.

How can I soar with the Eagles when I work with turkeys??

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
08-18-2009 01:10 AM  8 years agoPost 8
Raptor Pilot

rrVeteran

Northern Ireland U.K

My Posts: All  Forum  Topic

Many a liner ive used again like what your describeing and it worked for years after the rebuild. As long as the chrome or Nickle plateing is still on the bore then its useable, minor scores that you can see but cant detect with your finger i wouldnt worry about them. Give it a light hone to be sure. A new ring will bed into the liner in no time.

If it doesnt move and its meant too... use WD 40. If it moves and its not meant too...use duct tape!

PM  EMAIL  GALLERY  Attn:RR  Quote
08-18-2009 03:41 PM  8 years agoPost 9
bbaxter

rrApprentice

Central Illinois

My Posts: All  Forum  Topic

Many a liner ive used again like what your describeing and it worked for years after the rebuild. As long as the chrome or Nickle plateing is still on the bore then its useable, minor scores that you can see but cant detect with your finger i wouldnt worry about them. Give it a light hone to be sure. A new ring will bed into the liner in no time.
An O.S. Max ringed engine will not have a nickel plated liner. It will have a steel liner. Only the non-ringed engines have a plated liner, and if the liner's bad, you'll have to replace the piston/liner combination because they only come in matched pairs.

PM  EMAIL  Attn:RR  Quote
08-18-2009 10:26 PM  8 years agoPost 10
Raptor Pilot

rrVeteran

Northern Ireland U.K

My Posts: All  Forum  Topic

An O.S. Max ringed engine will not have a nickel plated liner
Sure i know that but what i said was as long as the chrome or Nickle plateing is still on the bore then its useable meaning if you have a ABN liner like a webra or a ABC liner like an OS then it is useable. I know these types come in matched pairs but the steel liner like the O.S Max ringed engines dont come in matched pairs. I think there sometimes is a misunderstanding in what some people pick out of what you say when you live half a world away. Im just adding my 2 p's worth.

If it doesnt move and its meant too... use WD 40. If it moves and its not meant too...use duct tape!

PM  EMAIL  GALLERY  Attn:RR  Quote
08-19-2009 02:41 AM  8 years agoPost 11
itsjojo

rrKey Veteran

North East Pennnsylvania

My Posts: All  Forum  Topic

Wow!
I checked back in and a ton of info here. Thanks. I didn't use a hone tool this time so I'll see what happens. I have rebuilt car engines and understand the honing process and seating rings. I didn't think they made tools small enough to get into that sleeve. I'll pick one up soon. Beats $45 for a new liner.

Thanks for all the advice!
Jojo

JoJo
Foreseeing My Flybarless Future!

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
08-19-2009 04:38 AM  8 years agoPost 12
GREYEAGLE

rrElite Veteran

Flat Land's

My Posts: All  Forum  Topic

Find some
Grey colored scotch brite, make sure it's 3M or Norton only. They make three or four abrasive grades. Green , Red, Grey, and maybe a Black. Not as aggressive, and you can sneak up on the glazing. It's a very sharp synthetic abrasive . Stuff your thumb in their and spin. You won't disturb the tolerencs or end up with a tapered bore.

Helps if you boil it prior in glycol 1st to check it.

Possibility exist's you leave the hone in for a split second too long, it's easy too remove .0015 in a heart beat or .003 on the I.D. reducing the long term life and a lousy fit of a stock ring.

Then their's the wear and tear on the new ring as it shears off the tops of the mountains, folds over the burr's, and fills in the valleys of the cross hatch.

Make it low risk and easy.

greyeagle

PM  EMAIL  GALLERY  Attn:RR  Quote
08-19-2009 12:56 PM  8 years agoPost 13
Against Gravity

rrVeteran

Pottstown PA

My Posts: All  Forum  Topic

Great tip
Greyeagle
I am going to try that on my HZ. Thanks that makes good sense

PM  EMAIL  GALLERY  Attn:RR  Quote
08-19-2009 01:47 PM  8 years agoPost 14
KevinB

rrKey Veteran

Saskatoon, Saskatchewan, Canada

My Posts: All  Forum  Topic

Just to clarify....
If you buy a hone like the ones pictured in dkshema's post, there is an adjustment on it to set the pressure that the abrasive pads push against the cylinder wall. You set that relatively low, and you should be using a slow rotational speed on the drill as well....like about 60 rpm or 1 turn per second. Last, hold the liner loosely in your fingers as you move the hone back and forth so the liner will align itself to the axis of the hone. If you approach it like this, you are NOT going to remove a bunch of material in a heart beat.

The first time I tried it, I had backed the pad pressure off to the minimum. After 2 or 3 five to ten second attempts, I actually increased the pad pressure because it wasn't doing anything to the glaze. If you have an old scored liner, practice on that first if you are worried about setting the right pressure. If not, start at the lowest pad tension and work up as needed.

The scotch bright will work as well, but it won't be as uniform a job as the brake hone. Also, be sure to clean the liner thoroughly after using scotchbrite because those little abrasive threads may break off or catch in the liner's ports. You don't want one of them going through your engine. Of course you should still clean the liner after using the hone as well.

KevinB

PM  EMAIL  GALLERY  Attn:RR  Quote
08-21-2009 09:17 AM  8 years agoPost 15
itsjojo

rrKey Veteran

North East Pennnsylvania

My Posts: All  Forum  Topic

this thread has been very informative for me. My engine has been going strong and I wish I had cross hatched the sleeve. I do have a few sleeves to practice on. That I'll do. I'll know better on the next rebuild. I have learned quite a bit here.
Jojo

JoJo
Foreseeing My Flybarless Future!

PM  EMAIL  HOMEPAGE  GALLERY  Attn:RR  Quote
WATCH
 1 page 2750 views POST REPLY
HelicopterEngines Plugs Mufflers Fuel › Os 50 H - Piston Liner sleeve - Reuse or not?
 Print TOPIC  Make Suggestion 

 6  Topic Subscribe

Friday, April 20 - 2:25 am - Copyright © 2000-2018 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online