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'Morning Rick - or maybe evening to you, First off, let me say that I am not over familiar with diesel engines - in fact the only ones I've ever had were in a Series IIa Land Rover, and my two Peugeot cars. I have a really bad feeling about this latest rebuild, but will try to ask questions that may lead you to a reasonable answer . . . . . incidentally, I am not being rude or aggressive in this, just recovering from a lack of coffee and a wild weekend :) Was the hard starting after this rebuild, or was this rebuild an attempt to fix the hard starting after the earlier rebuild? Just asking because the Ferguson diesel in its early form was reputed to be a bad starter from new I think, so you may be trying to fix the unfixable fix. OK, pistons are a sliding fit in the bore, supposedly. The ones you have are more than 1mm smaller in diameter than they should be, so they will be slapping about in the bore like a good 'un. This will not do the bore, the pistons or the rings any good, long term. In engineering terms, the fit you have is like waving your male appendage around inside a bucket. Having 'unburnt fuel sloshing around' inside the combustion chamber should (in my opinion) lead to excessive cooling and poor combustion, not excessive combustion temperatures, so should not lead to burnt injectors. My old LR diesel was so tired it would inhale oil from the sump, and run on that - and although that was deeply scary (runaway diesel), it never burnt injectors. You are correct in checking your timing, but I strongly suspect that the problems you now face are a result of the piston sizing being incorrect. For instance, are you using the correct rings? and if so, just how well are they supported by the new, smaller pistons? Or are you using another set of piston rings, that will 'fit'? 0.5mm either side off the piston, does not leave much for the rings to hold on to, does it? How did you calculate that your compression was 43% down on what it should be? What is the bore dia, and the stroke on the 23C engine? And should a 0.015 inch change in dimension over the piston area really make that much difference?? I think you may have slipped a decimal point, somewhere. If the compression figures were off a compression tester, then change those pistons back to the old ones!!!!! ! (Once you have checked your bores for damage, of course) The way I look at it is that if your compression really is that low, then you are losing large amounts of diesel and air into the sump (not good) due to blowby so the combustion is then running 'weak' and so hotter - hence your burnt injectors In short, I don't think the pistons you have are doing you any favours at all - sorry. If you really want to change your pistons, try emailing The Old 20 Parts Co here in the UK - battelle at btinternet dot com and see if they can supply some that fit - they may even be able to help solve the problem. You could also try www.holland-brand.co.uk. I have no connection with either of them and the usual disclaimers apply. Can any diesel heads out there add any more?
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