Webra 2.5 S Rebiuld Project

Webra Model 2.5 S
Manufacturer/Distributor Webra-Fein-Modelltechnik, Berlin, Germany
Year of manufacture 1951
2.45 Displacement DC (0.151 cu. In.)
Bore 14 mm (0.551 in.)
Stroke 16 mm. (0.630 in.)
Diesel Power Class
Cycle 2
Fixed type carburetor (without speed control)
Admission front rotary valve (crankshaft)
Crankshaft on bronze journal
Fuel:- / Castor oil / Kerosene /Ether
Worn Condition with missing parts before rebuild

Comment the "S" stands here stands for Seitenflansch (Side Flange) and not for "Sport" 

2 needle valve version shown below

This is the story of how I produced this lovely collectible vintage diesel engine

from this sorry collection of worn out junk parts: by investing many hours of painstaking work

and creating this final product, a fine running rebuilt Webra 3.5 S diesel engine

The condition summary before rebuild: missing connecting rod and counter-piston; incorrect propeller driver; badly worn piston and crank pin as well as an overall rundown condition; the crank pin when new measured 5 mm in diameter but, this one is between 4.67 and 4.84 mm, a sort of egg shape with a badly scratched surface; the soft copper gasket between the cylinder liner and the crankcase was also missing. The next few pictures show the making of this simple but essential part

After the final size of the inside and outside diameters is achieved by the machining operations the washer is carefully cut off with a Dremel tool, to prevent warping of the soft copper part 

Then a file is used to remove the sharp standing edges until we have a flat ring of soft copper

The making of this simple part took more than an hour of work to produce, which is why engine rebuilding has to be a labor of love

After all that work it now looks right and seals well, that's why I do this: the reward will be an easy starting reliable runner

Contra-Piston machined with a conical recess that matches the conical dome on the piston

All parts are cleaned; the crankcase buffed and scratches eliminated, the head repainted with heat proof paint~~slowly we are beginning to see the results of these efforts

The next step is to select a suitable wrist pin from my collection of needle bearings, one with the correct diameter to match the piston

These needle bearings are perfect for this application: made from hardened silver steel with a chromed surface all assuring a long life for the final part

Now we must make the small end of the connecting rod and the pin bore in the piston to match the size of the wrist pin

Grinding paste used to adjust the fit for optimal operation

End of preview
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French Micron 2.8 cc Diesel

Below: 1946/7 MKI Micron engine, like the engine featured in this page

 The MKII with spinner and front induction shown below

Data:
2.8cc MICRON Model DC D Mk. II
Manufacturer Micron Moteurs, Paris, France
Distributed by Micron Moteurs, Paris, France
Series / Serial Number s / n
YOM 1946
Displacement 2.8 cc (0.17 cu. In.)
Diesel Power Class
Cycle 2
Fixed type carburetor (without speed)
Admission rear over piston
Crankshaft on cast iron journal
Ether fuel Fuel / kerosene / Oil
Very Good Condition
Comments short stroke. 
Also fitted as standard equipment a tank with filler cover incorporated.

Comments:

Published on 5 Jan 2013 To day no rebuild story guys,...sorry,as the engine was a fast fix.I am very pleased with this very rare French Micron.I saw only this in 3 years on E-bay. Like I say in the clip,only some parts needs to be made.The hardest work was to unscrew the rear cover and get the crankshaft turning again and remove it. It was so badly glued together, that I had almost thought of giving up. Only after a long heating period and the addition of thin oil did the parts finally separate after 1 hour of struggling. The second big problem was the cylinder hold down screws. Somebody had already made an attempt to make them fit, maybe the thread was bad, so two threads at the front were 3 mm and the other was originally 2.5 mm. I thought at first,that this would be an easy fix,but later discovered that the liner was hardened, so there was no chance of drilling out the holes to 3 mm. Since  I had to decide on something, so I made from a stainless steel rod 2 special studs,one end M3 thread....other end M2,5 thread.. Also I made two regular studs of M2,5. .I also milled and tapped from steel four new M 2.5 nuts, so now everything will fit nicely together. Its a bit of a shame, as the original engine use 4 screws to connect the cylinder to the crankcase. But since I must make something out of it because, the compression was still great and connecting rod and shaft have no excessive play. The compression lever, extension, tank cover and the filler cover, carburetor clamp,and the prop driver assembly with the gaskets was an easy job..Actually the original engine has only a nut (Non metric!!) for the propeller,but in one of my books I saw the MK II with a nice spinner,so that's why I have decorated  him a bit with a brand new spinner.....he deserve it, as its a so lovely old engine. I tell myself to stop buying engines, as I am running out of space...but for rare engines is always a corner,right? By the way I know,the French Micron company made several engines up until the late 1960's and were always well made engines. Thanks for interest and remember; more interesting engine stuff on my channel. .Feel free to subscribe.

http://youtu.be/RU9FbAqEXO4

ED Hunter 3.5 cc mk IV

Model E.D. 3.46 DC HUNTER Mk. VI 

Manufacturer Electronic Developments, Ltd., England

Distributed by E.D., Surbiton, Surrey, England

Series / Serial No. 4122/9

YOM 1949

Displacement 0.211 cu. in. (3.46 D.C.)

Diameter 0.656 in. (21/32 in.) (16.66 mm.)

Stroke .625 in. (5/8 in.) (15.88 mm.)

Power output 0.25 HP @ 10,000 RPM

Diesel Power Class

Cycle 2

Adjustable Carburetor type (with primitive speed control)

Admission rear rotary valve

Crankshaft on bronze Journal bearing

Fuel: / Oil / Kerosene/ /Ether 

Condition well used but serviceable

Comments Classic English style, very solid construction and rear rotary valve. Steel sleeve

On 21th September 1954 ED prepared an RC Model Airplane and flew it nonstop from England to France from a chase plane

After 102 minutes airborne it arrived over Calle in France

My engine is equipped with a rare optional linked double butterfly throttle arrangement 

Shown below 

Its a very massive engine well made with lots of torque

Comments:

Published on 1 Jan 2013 Another British great and impressive diesel.The Hunter 3.5 cc. is a very powerful and well made model diesel engine in its day..It was made in different variations:.my engine is very old from 1949 but has zero play in the main bearings, or in the connecting rod. With only minor play in the wrist pin and weak compression due its age and running hours, but still a easy starter and ready to turn big props with ease. The E.D. company in Surrey made a long list of very interesting engines. Its the longest existing model engine factory in the UK. The range of there types of engines is endless...Who hasn't heard of the Bee's 1 cc? The Comp.Special and so on... The E.D. Racer 2.49 will be also soon shown and documented in my channel. Also a team-racer with great performance and therefor a great reputation. Thanks again to Modelenginenews.org for their treasure of information without which would have made my documentation on the background impossible. Its a highly recommended website, if you are interested in old model engines.I get "lost" there and spend many hours browsing...and find always something to focus my passion for this hobby. Also there you can find many tips how to restore your vintage engines. Thanks for interest and till soon. More great engines from my collection will be showing here. Ratings and comments are welcome!

http://youtu.be/uUrvE8IlUZw

 
Something a little different here, we are looking for some help to identify the origin of this mystery engine.

All my reference books for Czech and other European countries were of no help and after my lenthy research, it still remains a mystery engine to me. 

 Welcome back to Peter's Engine collection for the running of a beautiful old long-stroke diesel which we found on Ebay.de. Sold as maybe a Czech engine but it could be anything as the cylinder looks like it could be a copy of the French Micron.

 We did't open it up for measurements but judging from its size at a guess I would say its about 3.5 cc's. The best lead to its origin is another mystery engine offered on Ebay.uk and described as a possible Jiri Patrman engine. Both engines seem to have very similar looking fuel tank designs.

I am even not sure if it is a replica engine or the genuine thing, its serial number (19) is sramped on the backside of the prop-driver.

 OK! Lets bring it outside and see if we can make it smoke.