Crankcase hairline fracture?

[Andie]

Hello - i have been cleaning down my Li today and noticed what looks like a hairline crack running from the gear cable block, and reaching down the back of the engine casing block.

Obviously a bit worried - i've only had it a fortnight - is this as serious as I'm thinking? - i.e. a total strip down and alloy weld... I guess I already know the answer but any advice would be appreciated. I live in leeds so am near Chiselspeed but don't have the expertise or tools to strip down a complete block.

Thanks!

[petemaisey]

I see some casting 'spider trails' coming from the block area. They can look like cracks in certain a light. Are you sure it is a crack? I have not seen a crack there before on an engine. Is it an ex sprinter engine?
Pete

[Andie]

Hello Pete - thank you - its a '63 series3 125, pretty bog standard and original AFAIK (iseo blue), I was hoping it was a casting mark.
I have wire wooled it though. is it worth using a dye perhaps?

here's another angle

[MickYork]

I had something similar on an Indian casing (different area though). I "dremmeled" the surface and there was no crack underneath.....so just a casting mark

[Andie]

Thanks Mick. I guess maybe i should first pop off the crankcase cover and check the edge and inside of the block.

[Captain Pugwash]

Looks more like casting marks to me...

[HxPaul]

Looks more like casting marks to me...

+1

[JETEX]

+2. If it was a crack, I'm sure there'd be some oil seepage around it.

[CHRIS in MARGATE]

Dremmel the area and I think you'll find nothing to worry about. Not a stressed area.

[Andie]

Thank you. I'll get the dremmel out.

[xenia1]

Ive seen new old stock casings with marks just like that, its most likely as already mentioned a spider casting imperfection and purely superficial.

Andy

[Andie]

Thanks again. On cleaning the rest of the crankcase/engine block i spy many more spiders trails and casting marks. All good, must admit I've not had a Lambretta since 1989 (a ratty series 2 that was held together with string) so keep expecting the wheels to fall off ... which i am sure they won't.

Also I won't be taking the crankcase off until I get a torque wrench next payday.

However I have one loose stud - the one on top just right of the clutch arm. I have bought an 8mm - 6mm oversize stud from MB... if I find a decent mechanic/engineer would they be able to drill and tap this in situ? Just wondered if anyone had done this before or if its a definate no no, in which case I'll have to have a rethink.

Thanks again. I should probably find a club in Leeds I guess. I used to be in one in Milton Keynes in the 80's where we paid subs and had a garage and more experienced guys would help us out (i wasn't a member for very long as I moved).

Cheers!

[CHRIS in MARGATE]

You weren't the Treasurer were you ??

[Andie]

not guilty! I tried googling them and theres no records though...

[steve_lawrence]

I once bought a new SIL 200 engine casing. It was full of marks like the one you have shown and they were all casting marks, not cracks. Always worth getting an expert to check it for you if you are unsure.