markjonesx 1 Posted January 20, 2012 Report Share Posted January 20, 2012 Having done some reading on 900 series engine builds, I have a question regarding the liner to engine block "Nip". The manual says that you should have a "Nip" of +0.003 -0 to +0.005 in. Do all the Liners come exactly the right size? if your our of tolerance what do you do? Quote Esprit S1, 238G, Blog Online Photo's This car was most definately hand built, NOTHING FITS! Link to post Share on other sites
Sir Paolo 5 Posted January 20, 2012 Report Share Posted January 20, 2012 In theory liners are supposed to be made to the right tolerances, so yes. But 3-5thou is about the thickness of a piece of thin paper, so the margin of error is minute. After market liners may or may not be to the same standards, although I understand Westwood ones are OK. I still had problems even though I bought genuine Lotus pistons/liners. I had to have the block deck skimmed by a specialist to bring nip within tolerances. It depends it the nip is too high or too low on what course of action you take. Liners do not all have to be exactly the same nip, the accepted difference betwen them as the WSM states is 1thou. Another thing to be mindful of is to keep the heights uniform i.e. install the liners so that they go from high to low, or low to high (within tolerances of course), but not low to high to low or vice versa. Quote Link to post Share on other sites
910Esprit 544 Posted January 20, 2012 Report Share Posted January 20, 2012 measure and record all the liners 'nip' in the one bore. Then use one liner and measure and reord the nip in each bore. You can then arrange the longest liner in the deepest bore to the shortest liner in the shorest bore. There are also 2 permutations of rotation for each liner. I've always got in spec using this approach. Quote Link to post Share on other sites
markjonesx 1 Posted January 20, 2012 Author Report Share Posted January 20, 2012 There are also 2 permutations of rotation for each liner. What does this mean? Quote Esprit S1, 238G, Blog Online Photo's This car was most definately hand built, NOTHING FITS! Link to post Share on other sites
andydclements 788 Posted January 21, 2012 Report Share Posted January 21, 2012 You can turn the liner through 180 degrees so that what was exhaust side is now inlet side. It works on the basis that there may be 1/2 or 1 tough of run-out around the base of the liner or block face that it mates to, so turning it may lower or raise the top of the liner slightly. Quote Link to post Share on other sites
markjonesx 1 Posted January 22, 2012 Author Report Share Posted January 22, 2012 What sort of gauge do you use to check the nip? Normal DTI? Anyone got a pic/link? Quote Esprit S1, 238G, Blog Online Photo's This car was most definately hand built, NOTHING FITS! Link to post Share on other sites
lotus4s 24 Posted January 22, 2012 Report Share Posted January 22, 2012 There is a specific tool for the job which is basically a dial indicator and bar mount but lacking that, you can use a straight edge across the bore and feeler gauges. Quote 1995 S4s Link to post Share on other sites
910Esprit 544 Posted January 22, 2012 Report Share Posted January 22, 2012 I use a DTI, with the stand simply located on the head surface of the block adjacent to each bore in turn. A bit fiddley, but perfectly repeatable. Quote Link to post Share on other sites
Sir Paolo 5 Posted January 23, 2012 Report Share Posted January 23, 2012 I'd avoid using feeler gauges, there too fiddly when trying to achieve such critical measurements. I use a depth micrometer and a machined flat bar with holes that line up with the liner and block, when in position. Quote Link to post Share on other sites
yeller77 114 Posted January 25, 2012 Report Share Posted January 25, 2012 Reading this thread with interest as I've now finally got my block on a stand after being in bits for ages and the nips are all over the place! Quote Link to post Share on other sites
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