jono Posted November 11, 2014 Share Posted November 11, 2014 how many of you have built or rebuilt EA engines and used preloved pistons from other EA engine? It is not a practice I have done before, feel it sounds a bit low budget risky, and is different from a tear down and reiring where pistons go back in same bores. It sounds like it has been done, or intended to be done by a few people in here. Do you also measure up pistons and bores to be within spec, or just slap it all back together and go on your merry way ?? Any problems foreseen or experienced ? Link to comment Share on other sites More sharing options...
Crazyeights Posted November 11, 2014 Share Posted November 11, 2014 I have done this and it works fine. Just make sure all the measurements check out first. Link to comment Share on other sites More sharing options...
djcommie Posted November 11, 2014 Share Posted November 11, 2014 (edited) Pistons don't really wear that much other than the skirts and where the wrist pin rides. If those are fine, you'd likely not have any trouble. Edited November 11, 2014 by djcommie Link to comment Share on other sites More sharing options...
skishop69 Posted November 12, 2014 Share Posted November 12, 2014 +1. If the cylinder walls and piston skirts aren't scored and your measurements are good, should be no issue at all. Personally, I would take some fine Emmery paper or a Scotch Brite pad just to lightly scuff the cylinder walls to allow the rings to seat better. 1 Link to comment Share on other sites More sharing options...
Ibreakstuff Posted November 12, 2014 Share Posted November 12, 2014 +1. If the cylinder walls and piston skirts aren't scored and your measurements are good, should be no issue at all. Personally, I would take some fine Emmery paper or a Scotch Brite pad just to lightly scuff the cylinder walls to allow the rings to seat better. I agree with deglazing the cylinder walls, but be very careful with scotchbrite pads. If any of the fibers make their way into the oiling system, it will ruin your new bearings. Ball hone would be the correct DIY tool to use (Flex hone 00695767). 1 Link to comment Share on other sites More sharing options...
skishop69 Posted November 12, 2014 Share Posted November 12, 2014 Yes on the ball hone, but if your measurements are loose, you might take too much out and put in the wrong cross hatch pattern if you're not familiar with using one. DEFINTELY yes on making sure you don't get pad particles left behind and I should have mentioned when you scuff the cylinders, you need to do it in a circular pattern around the circumference of the cylinder, not up and down. Link to comment Share on other sites More sharing options...
jono Posted November 12, 2014 Author Share Posted November 12, 2014 OK, thanks Flexhone is about mates shop somewhere. Not sure what I am gonna try when time comes..... Link to comment Share on other sites More sharing options...
Gloyale Posted November 13, 2014 Share Posted November 13, 2014 Also check the Bore marks on the block and the pistons and match them A,B, or C size.... IIRC EA bore marks are on the bottom of the block? perhaps even on the oil pan mating surface?>>? Link to comment Share on other sites More sharing options...
Ibreakstuff Posted November 13, 2014 Share Posted November 13, 2014 (edited) Also check the Bore marks on the block and the pistons and match them A,B, or C size.... IIRC EA bore marks are on the bottom of the block? perhaps even on the oil pan mating surface?>>? Weird. All 12 pistons of the original pistons from my 3 turbo short blocks do have a "B" on the crown. And the "B" stamp on the shortblock halves isn't on the oil pan mating surface (which has numbers), its vertically on the exterior of the block directly under each cylinder. My 87, 88, and 90 FSM's don't seem to reference the A, B, C sizes. It only shows the std, +.25mm, and +.5mm sized pistons. Were the other sizes actually avail for turbo block/pistons or did they just pull BBBB blocks from the line? These are turbo pistons correct? 12006AA220 .25 mm os 12006AA230 .50 mm os And the rings? 12033AA000 (NPR SWF20057) Edited November 13, 2014 by Ibreakstuff Link to comment Share on other sites More sharing options...
Gloyale Posted November 13, 2014 Share Posted November 13, 2014 Seems like most blocks are BBBB..........since that is the "middle" size it's probably the standard they shot for.....and the A and C pistons are for blocks that have just a slight variation..... I can't find reference to it in the FSM....but I have seen "A" pistons.....never seen a C......... EJ FSMs clearly specify this.....I think it was left out of the EA FSMs........most of the time a rebuilder will go with the .25 or .50 mm oversize. Which are way bigger than the A, B, and C pistons. Link to comment Share on other sites More sharing options...
jono Posted November 13, 2014 Author Share Posted November 13, 2014 now, the last suggestion of piston V block ID marks is one I did not expect to hear. The letters represent not oversizes though ? More super specific piston to bore sizes, clearances, years ? So, I need to be aware of these measures before I go shove EA82T pistons in an EA81 block ??? Link to comment Share on other sites More sharing options...
Ibreakstuff Posted November 13, 2014 Share Posted November 13, 2014 Seems like most blocks are BBBB..........since that is the "middle" size it's probably the standard they shot for.....and the A and C pistons are for blocks that have just a slight variation..... I can't find reference to it in the FSM....but I have seen "A" pistons.....never seen a C......... EJ FSMs clearly specify this.....I think it was left out of the EA FSMs........most of the time a rebuilder will go with the .25 or .50 mm oversize. Which are way bigger than the A, B, and C pistons. Sounds plausible to me. I do like how the EJ sizes are clearly defined, it almost allows for drop in forged pistons without a bore gauge and mics (NOT RECOMMENDED) on brand new short blocks. Actually I think Manley sells A/B pistons now. Link to comment Share on other sites More sharing options...
Ibreakstuff Posted November 13, 2014 Share Posted November 13, 2014 now, the last suggestion of piston V block ID marks is one I did not expect to hear. The letters represent not oversizes though ? More super specific piston to bore sizes, clearances, years ? So, I need to be aware of these measures before I go shove EA82T pistons in an EA81 block ??? The letters represent slight variations in the bore and pistons sizes (+/- .0005"), they did this to achieve the correct piston to wall clearances without custom sizing/reboring. The only 100% surefire way to confirm is with a micrometer and a bore gauge, esp if they are from a different motor. Link to comment Share on other sites More sharing options...
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