norton engine number??

[codfish]

Hi, can any one please help me with this engine, I found it with the numbers misaligned and I canīt id it as it is writen (with the number 1 out of aligment).
itīs writen E 1 8xxx .I didnīt measured the bore yet as it is out of my hands. Tha other parts are from different years ( like the frame is 47-48 year).
I can tell the year but I canīt find the model and the number( 8xxx) doesnīt match with the year letter (E)
Thanks in advance.

[RichP]

It doesn't really make sense as it stands. 'E' is the 1950 code but '1' wasn't used as a model identifier. Neither 18xxx nor 8xxx would seem to fit a 1950 build.

What type of engine is it ? OHV or SV ?  Is it a post-48 engine ?

I think that you'd need to add a photo of the drive side crankcase for any one to judge if it is an original stamping.

[codfish]

that one image I managed to get. I will post more 

[Norton55]

Hi codfish,
I don't think the number in the picture posted is the engine number. The engine number should be punched in on the left crank case right below the barrel. If its a single cylinder, the bore and stroke is usually also around the engine number. example, 79 x 100 for the 500cc singles.

[33d6]

Hi Codfish,
This is a casting number, not an engine number. You are far from alone in confusing the two. Its very handy to know the difference between them as there are several casting numbers scattered about your bike.
A casting is always made from an individual pattern and that pattern has its own individual number. This is to prevent mistakes in the foundry. The pattern maker deliberately attaches raised numbers to the pattern so every casting made from it shows the same pattern number over and over. A raised number cannot be confused with a number stamped into the casting because it an integral part of the casting. If you look around your engine you may find a similar style of raised number on both the barrell and the cylinder head as these are castings also.
Engine, frame, and gearbox numbers are identifying numbers and unique to each item. No two have the same number. They serve a different purpose to the casting number so are visually different from them.
Just remember casting numbers are always raised and part of the parent metal and identifying numbers are always stamped in to the metal. Casting OUT, identifier IN.
Once again, you are far from the first to confuse the two so hopefully this long explanation will help other people also.
Cheers, 

[codfish]

Hi, 33d6 and norton 55, thanks for your fast answer!! I was really stupid to mix raised numbers to stamped nrs!!after your great explanation (I printed it) my knowledge  is enhanced!
I finaly founded the number:
B3 12xxx Q 79x100 1947
and from what I found itīs a 18 model from 1947 with quietening ramp cams.
I have two frames 10XXX. Do you know if itīs right (historic) to fit this motor in that frames?(one is swinging arm and the other is plunger)
Thanks again for all and sorry for my broken english.

[Norton55]

Hi codfish,
Since the engine is from a model 18 it would actually have a rigid frame with Norton long road holders in the front. If your plunger frame number is 10XXX, it is most likely from 1947 as well and you could use that and essentially have a Norton ES2 (which was basically the model 18 engine in a plunger frame). Swing arm frames were introduced from the 1953 model bikes so that would be from a bit later than your engine.