myson Posted January 30, 2010 Report Share Posted January 30, 2010 Hi, Just had a look at the underside of the crank cases and I am not sure if they are 100% ok. On the gearbox drain plug side there is a ridge (crack?) that apears perfectly straight for about 1"then turns perfect 90 degrees and runs for another 1". In the center of cases ( where the casting has a hole running back up into it on about a 45 deg angle) there is a similar ride. Could they be casting marks or has something gone a bit wrong at some time. Photos of some in good condition would be appreciated, Cheers Quote Link to comment Share on other sites More sharing options...
feetupfun Posted January 30, 2010 Report Share Posted January 30, 2010 Sounds normal to me. How about you post a photo of yours? Quote Link to comment Share on other sites More sharing options...
myson Posted January 31, 2010 Author Report Share Posted January 31, 2010 Cheers, I will upload photos today, Quote Link to comment Share on other sites More sharing options...
myson Posted February 1, 2010 Author Report Share Posted February 1, 2010 Hi sorry for delay here is photo, what do you think? photo Cheers Quote Link to comment Share on other sites More sharing options...
triple_x Posted February 1, 2010 Report Share Posted February 1, 2010 Hi I have got exactly the same lines on my M80 crankcases. They are simply the die/mould break lines so that the cast crankcase can be removed from the die once cooled. They are located by the redundant speedo drive and drain plug. I suspect there were pins in the tooling to form a holes prior to drilling out and tapping the finished spec. If you look at an Airfix kit you will always see the tooling lines as well as ejector pin marks. Hope this helps. Martin Quote Link to comment Share on other sites More sharing options...
myson Posted February 2, 2010 Author Report Share Posted February 2, 2010 Cheers, thanks for help, spot on as usual. I can build top end back up now with no worries. Quote Link to comment Share on other sites More sharing options...
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