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Piston orientation
Posted: Wed Apr 23, 2008 7:50 pm
by youngun
Just a quick, but crucial, question. The crowns of my pistons have "front" stamped on them, and all have a 2 with a little arrowhead above it. Do these 2's with the arrowheads point towards the 2's on the block, and does the front stamp point towards the front of the engine? The manual is a bit vague on this subject...i.e. no pictures!
cheers,
YG
Posted: Wed Apr 23, 2008 7:54 pm
by superchargedfool
if your pistons are still on the rods then they only go in the correct way round anyway.
Posted: Wed Apr 23, 2008 7:56 pm
by bigginger
Front to the front - '2', I've read, refers to the grade of the piston, I think - but I'll check that
Wrong again - it's an "identification" number - would state the 'Over' size if they were oversize...
Posted: Wed Apr 23, 2008 7:59 pm
by youngun
superchargedfool wrote:if your pistons are still on the rods then they only go in the correct way round anyway.
Correct, but i still dont know which way that is!
Posted: Wed Apr 23, 2008 8:00 pm
by youngun
bigginger wrote:Front to the front - '2', I've read, refers to the grade of the piston, I think - but I'll check that
Front being the water pump side of the engine?, (on the Jowett javelin engine the front is the back....!!)
Posted: Wed Apr 23, 2008 8:00 pm
by bigginger
With 'front' to the front of the car
, so yes, where the water pump, fan, headlights etc are - the front, in fact
Posted: Wed Apr 23, 2008 8:23 pm
by youngun
Nice and conventional then!
Posted: Wed Apr 23, 2008 9:16 pm
by bmcecosse
Front is front!! The 2 in the diamond was supposedly indeed a 'grade' mark - suggesting the pistons were sized carefully and fitted to matching sized bores. If true - must have been just slightly labour intensive. Easier I would have thought to just make the bores right first time - and use standard size pistons. But hey ho - that's BMC for you!