gsalort1978

Hi people

I have al old but "hot" OS .25 VF abc and the crome of the cylinder is damaged. I sent an e-mail to TowerHobbies because in my country there isn't an OS dealer, an Tower Hobbies said me: "Sorry, we do not have that part. It has been discontinued. We don't have any information about where you may be able to find it."

OSMG4872 22803010 Cylinder & Piston .25 V


www.osengines.com/parts/xr12840.html


Anybody know where I can buy it? I don't want to throw my engine in the trash.

In the case of not find the part, can I adapt other piston and liner and then cut the transfers and boosts with my Dremel?

I have been thinking in buy a OS. LA or FX piston and liner and put in the crankcase. The bore and stroke of OS 25 VF, LA and FX are the same:

Bore: .709" (18.0mm) Stroke .630" (16.0 mm)

Also an GMS .25 ABC have the same dimension.

Please, opinions.

Gabriel.

stg61abc

Gabriel, nice engine. The original OEM part will not be easy to get, but not impossible.
Another way is to try to contact the Controline speed fliers, RC cars racers and tuners in your area. These people does "wonders" with engines, and many of then even custom manufacture or adapt components to hop-up engines. I saw some hibrids buggy and small 12 rc car engines benn addapted to fly C/L and RC, with custom heads, carbs etc...
I know that in Argentina there are very good modelers and very high skilled craftsman, so give it a try.
So the source will be to try with the people from: RC Pylon Racing, C/l combat, C/L racing & Speed etc... and correlated...
One of the sollutions may be there ...
Good luck

Motorboy

Gabriel, sorry to tell you, the "ABC" in OS engines are not a real ABC cylinder/piston. The coating are nickel and will peel of the brass cylinder.

It is a worth to try the cylinder/piston set from GMS engine, but be careful to use Dremel if you are not skilled to handle the tool careful. Better to use needle file or diamond needle file to file away the cylinder material to adjust more precise size of ports. Measure carefully - it's easier to remove metal than to put it back

jeffie8696

Idid not know GMS made a rear exhaust engine.

earlwb

You know the GMS 25 ABC cylinder and piston just might fit. if not it ought to be really close.
You may be able to carefully file the ports to match too, but I would leave them alone as you stand a chance of damaging the chrome plating on the cylinder and it'll peel on you again.

jeffie8696, what they do is simply rotate the cylinder 90 degrees and slide it in and it'll work as a rear exhaust then.

gsalort1978

People

OS Engine Support set me this e-mail

Gabriel,

Thank you for your recent email. Unfortunately that part is
discontinued and no longer available. There is a hobby shop in Michigan
that sells some parts to older discontinued engines, they may have the
part you are looking for.

Pete's Hobbies
585 VanAllen
Wyoming MI 49548

(616)-245-3106

E-mail: [email protected]
Web Site: www.peteshobbies.com or www.petesrc.com

I sent an e mail to him.

gsalort1978

stg61abc

Thank you for say that "in Argentina there are very good modelers"... I hope that you are not joking.

The best.

Gabriel.

rcdude7

My Feedback: (264)

The OS .61vf used the same sleeve as the .61fsr, just rotated to put the exhaust port in the rear.

jeffie8696

Cool. Good to know, if I ever get my hands on a rear exhaust engine. Then again my MVVS is convertible, you have to just un bolt the cylinder and rotate it.

NM2K

My Feedback: (14)

Yes, but each time you rotate it, you need a new piston/liner combo - true?


Ed Cregger

jeffie8696

Yea that is explained in the instructions. IF you can get them! Mine has a bad piston so it probably wouldnt make a lot of difference.

stg61abc

Gabriel, I´m not joking at all Amigo. I saw very impressive planes from Argentinean pilots here in Brazil in some past Model meetings, and all I must say to you is that they were "Impressive" at least, like a giant C-130 Hercules with four Webras .91 engines and a wonderful twin ducted fan Phanton F-4 with two OS 91 VRDF´s..
Also I have some issues from a nice Model Magazine from your country called "El Aeromodelista", that are very good, and also show some nice plans and masterfully well built planes.
I also had the privilege to watch an exhibition from Quique Somenzini some years ago, flying some giant 3D models, that i couldnt believe in my eyes....
Sincerly , is what I thing about

Mr Cox

Jeffie, Topmodel has several parts in stock, which size do you need, 26?

http://www.topmodel.fr/product_detail.php?id=11951

gsalort1978

Thank you

fizzwater2

My Feedback: (61)

there's an OS 25VF in the RCU classifieds right now.. no, it's not mine, nor do I know the seller. Just thought you might be interested.

gsalort1978

Thank you, I watched the iten.

jeffie8696

Mr Cox I thank you , Ilooked through the listing and did not see a piston for my GFSr 40. Not a problem, Ihave many other engines in front of this one to use so it can wait.