joeferret Posted January 13, 2015 Share Posted January 13, 2015 I found a brass data plate on my 1954 Canadian Army Ferret MK1 located on the right side of the engine near the bottom..Can some one help me decipher it please ? I am really interested as to where Workshop 27 was and about the Bore,Main and Throws...... RCEME Rebuilt Engine Workshop 27 Date 15 12 65 Inspected by (blank) Engine job number 2404 Cyl Bore 000 Main 000 Throws 000 Thank you all for any input. Quote Link to comment Share on other sites More sharing options...
bobfett Posted January 13, 2015 Share Posted January 13, 2015 (edited) If I've understood your question properly, I think this is what you're asking about? Cyl Bore/Mains/Throws sounds like it refers to the size of various surfaces within the engine. Cyl bore is how "oversize" (compared to a brand new engine built to spec) the cylinder bore is. On a brand new engine it's 0.000" oversize (hence your 000) As the engine wears, the cylinders start to get fractionally larger (usually in an oval shape IIRC). Eventually, come overhaul time, the cylinder is rebored back to a completely circular shape but slightly oversize. Usually something like +0.020" (020), then +0.040" (040) as a second step. Matching fractionally oversize pistons/piston rings are fitted to ensure a good seal. Similar principles apply to major bearings within the engine- Mains are the bearings which the crankshaft rotates on, and throws are the bearings by which the connecting rods connect to the crankshaft. Again, these surfaces wear as the engine ages, and again they are machined to remove wear. However, in this case the bearing journals on the crankshaft are machined fractionally (0.020"/0.040") smaller (undersize) to remove any uneven wear, and slightly thicker bearings are fitted (in the case of replaceable shells) or the bearing is relined and ground to the new size. Edited January 13, 2015 by bobfett Quote Link to comment Share on other sites More sharing options...
joeferret Posted January 13, 2015 Author Share Posted January 13, 2015 If I've understood your question properly, I think this is what you're asking about? Cyl Bore/Mains/Throws sounds like it refers to the size of various surfaces within the engine. Cyl bore is how "oversize" (compared to a brand new engine built to spec) the cylinder bore is. On a brand new engine it's 0.000" oversize (hence your 000) As the engine wears, the cylinders start to get fractionally larger (usually in an oval shape IIRC). Eventually, come overhaul time, the cylinder is rebored back to a completely circular shape but slightly oversize. Usually something like +0.020" (020), then +0.040" (040) as a second step. Matching fractionally oversize pistons/piston rings are fitted to ensure a good seal. Similar principles apply to major bearings within the engine- Mains are the bearings which the crankshaft rotates on, and throws are the bearings by which the connecting rods connect to the crankshaft. Again, these surfaces wear as the engine ages, and again they are machined to remove wear. However, in this case the bearing journals on the crankshaft are machined fractionally (0.020"/0.040") smaller (undersize) to remove any uneven wear, and slightly thicker bearings are fitted (in the case of replaceable shells) or the bearing is relined and ground to the new size. Bob, Thanks for the reply...My Bore/mains/throws are listed as 000 so that would be new then that I would understand on a new engine but mine was rebuilt ? I am wondering why they didn't put the machining down as you stated... Quote Link to comment Share on other sites More sharing options...
bobfett Posted January 13, 2015 Share Posted January 13, 2015 Bob,Thanks for the reply...My Bore/mains/throws are listed as 000 so that would be new then that I would understand on a new engine but mine was rebuilt ? I am wondering why they didn't put the machining down as you stated... That I'll have to leave to the real experts on here- I'd missed that bit when I typed my reply! Quote Link to comment Share on other sites More sharing options...
Richard Farrant Posted January 13, 2015 Share Posted January 13, 2015 Joe, The fact that your engine rebuild plate is all zeros means it probably had a new crank fitted and block was linered back to standard. Quote Link to comment Share on other sites More sharing options...
joeferret Posted January 13, 2015 Author Share Posted January 13, 2015 Joe,The fact that your engine rebuild plate is all zeros means it probably had a new crank fitted and block was linered back to standard. That's what I was guessing and I was hoping that you would comment on it thank you Richard.. Now I need an old Canadian Soldier mechanic to tell me where Workshop 27 was on December 15th 1965 ? Thanks to all. Quote Link to comment Share on other sites More sharing options...
Starfire Posted January 14, 2015 Share Posted January 14, 2015 Mine is mounted on the top of the rocker cover on the Saracen. I got new liners and a machined crank... 32 years ago! Cheers, Terry Quote Link to comment Share on other sites More sharing options...
robin craig Posted January 14, 2015 Share Posted January 14, 2015 Joe, I did some digging around tonight, didn't come up with a definitive answer but have some leads. Have sent an email to an EME knowledgeable person. Standby R Quote Link to comment Share on other sites More sharing options...
joeferret Posted January 14, 2015 Author Share Posted January 14, 2015 Joe, I did some digging around tonight, didn't come up with a definitive answer but have some leads. Have sent an email to an EME knowledgeable person. Standby R Thank you very much Robin....We need more old Canadian Army Soldiers to get involved.....Would sure like to have them share their Ferret pictures and stories.... Thanks again . Quote Link to comment Share on other sites More sharing options...
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