Monday, March 10, 2014

Webra Winner 2.5 cc




Model

WEBRA WINNER II
ManufacturerWebra-Fein-Modelltechnik, Berlin, Germany
Distributed byWebra-Fein-Modelltechnik, Berlin, Germany
Series / Series Issues / n
Year of manufacture1974
Displacement2.46 cc (0.150 cu.-In.)
Diameter14 mm. (0.551 in.).
Career16 mm. (0.630-in.)
Power ClassDiesel
Time2
Type of carburetorFixed (no speed control)
AdmissionRotary valve front (crankshaft)
Inner bearingNot
Bearing outerNot
Crankshaft on crankcaseIf
Crankshaft on bronzeNot
FuelEther / Petroleum / Oil
ConditionNew
CommentsRange of Webra sport. Motor without ball bearings, sleeve steel radial piston transfer and mehanita. Motor designed for the general public, uncomplicated and easy operation.Maintains a strong resemblance to the Webra Record last generation.

Published on 2 Mar 2014
In this episode you can see how this lovely old school long-stroke runs.The engine is actually as old as I am and was offered to me for rebuilding. Due to the lose of the original piston, connecting rod and wrist-pin the rebuild was a bit more difficult than it normally would be, to make this old beauty into a runner again. I used for a pattern a piston from another engine and a simple dummy connecting rod made up from sheet aluminium to get the right distances correct specially the eye to eye dimension from big end to small. I got the needed sizes pretty well and very close to what it should be. The run-in the clip is the 4th run after the rebuild and the engine is still a bit tight at top dead center, so more runs are needed to get the right fit for the new piston and liner combination.. The engine starts very easily, as is expected of a long-stroke, but all Webras have these nice properties.The Webra engines were always very well made and were known for the superb internal fits and finishes. All of these factors resulted in them also being superb starters.
The bore in the crankshaft for induction is pretty small, so the engine could be easy tuned a bit for extra performance by simply opening up the bore. The again this engine was never build for fast rpm, but more as a solid sports motor that can swing larger propellers..Running it with a 7 x 6 is not recommended by the makers. .A 8 x 6 will be good for combat, as long you don't run it over the max. rpm. The 10 x 4 old wooden prop moved a lot air and the engine is not run in yet.
I miss having the Komet and Winner in my collection......so maybe one day I will get lucky and make this lovely "Webra Family" of mine complete.


 Dummy Connecting rod used to establish required dimensions and engine timing

 Making the new piston





 All new parts ready for assembly




 visual check to confirm that the arrangement is true for correct engine operation
 Still missing its spinner but ready for operation
 Mounted in the test stand with a wooden 10 x 4 Top-Flite propeller mounted 

Clip of the fourth run after the rebuild