VERY strange block problem
Turbo Mini Forums

Right here goes:

I have a 1275 block from an Allegro (pre A+ block, same as 1275 GT)

I delivered it to my machinist a few days ago to get it honed to 020.

He called me and said he had gotten in trouble, there was a ring with very hard material down the bore that the honing couldnt machine...

I thought it sounded strange but went to check it out today.

About 1 cm from the bottom of cylinder on it starts, then 15 mm further up it stops again. Between here its very hard. its normal both above and below this "ring".



It can barely be seen in this picture. The border between the ring and the rest of the cylinder was not visible before honing, and is only visble now due to the fact that the honing cant remove material here.

it was a bit like that in all cylinders, but was fixable in all but cylinder one. It goes all the way around the bore.

What is this?!?!?

Edited by miniminor63 on 24th Oct, 2007.

probably a joint where they poured the first half on friday , and put the rest in on monday,lol


carl

WWW.FORCE-RACING.CO.UK PLEASE CLICK HERE

he he, but why so hard? also what would you do about it? my machinist suggested boring it very close to tolerance on the next oversize, and then hone as little as possible.

can you feel the bump,??.
if not are you not tempted to ignore it as it dos not interfear with the rings.

honing too close to tollerance is not such a good idea as you can be lesft with a light hone that still leaves some rough cuts in the wall,

Edited by fastcarl on 24th Oct, 2007.

WWW.FORCE-RACING.CO.UK PLEASE CLICK HERE

yes, can definately feel it! it goes from big diameter to smaller on the ring, and then up in diameter again.

Edited by miniminor63 on 24th Oct, 2007.

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=125315

I cant see any reason for it to be like this other than what FastCarl said, lol, to be honest, knowing the british motor industry when this block was made, i wouldnt be surprised if it actualy was that, what was wrong with it. 'Tools down lads, all out , untill the issue is rectified' cries the Union Representative

as long as it does not interfeer with the rings in the stroke and the piston skirt is clear!........ does not catch your ...OK!