Outrage Posted January 27, 2008 Share Posted January 27, 2008 Hey all, I've bitten the bullet and taken off the head of my 2.25 NAD in an effort to cure the plumes of smoke eminating from the exhaust. Heads going to a reconditioner for a looksee/cleanup, injectors are going for a test/cleanup and i'm going to replace the piston rings and the bearing shells on the connecting rods. Question is........ Is there an easy way that i can determine what size bearing shells and piston rings I need from looking at the old ones? Cheers, Lee Quote Link to comment Share on other sites More sharing options...
Les Henson Posted January 27, 2008 Share Posted January 27, 2008 They will have 'std' stamped on them, although this isn't always the case if they have been replaced in the past. Les. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 27, 2008 Share Posted January 27, 2008 Oversize pistons have '0.020', '0.040' etc stamped in the top of the piston -you need to clean them up well to read it though. Bearing shells have the undersize figure stamped on the back of the shell, where there is no movement so they don't wear away Quote Link to comment Share on other sites More sharing options...
Outrage Posted January 27, 2008 Author Share Posted January 27, 2008 Oversize pistons have '0.020', '0.040' etc stamped in the top of the piston -you need to clean them up well to read it though.Bearing shells have the undersize figure stamped on the back of the shell, where there is no movement so they don't wear away Great, thanks for the replies i'll have a better look later, was hoping it was that easy! Cheers, Lee Quote Link to comment Share on other sites More sharing options...
B reg 90 Posted January 27, 2008 Share Posted January 27, 2008 Lee, if you fancy an upgrade in power I have a good 2.5 Turbo diesel for sale. Only 75k miles from new. Can be seen running in vehicle. PM me if you are interested. Adrian Quote Link to comment Share on other sites More sharing options...
Outrage Posted January 28, 2008 Author Share Posted January 28, 2008 Oversize pistons have '0.020', '0.040' etc stamped in the top of the piston -you need to clean them up well to read it though.Bearing shells have the undersize figure stamped on the back of the shell, where there is no movement so they don't wear away Hi, thanks for the earlier input. Ive had a better look at the bearing shells they've got "Rover 527172" and "NB 306 DC" stamped on them. Are these standard shells? Cheers, Lee. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 29, 2008 Share Posted January 29, 2008 If there is no undersize markings then I think they should be, but someone with a part number list can probably tell you with more conviction.... But looking at this page : http://www.christianhollumimports.ca/page10.html it looks like they are standard diesel big end bearing shells..... Like I say though, I might be wrong =) Quote Link to comment Share on other sites More sharing options...
Les Henson Posted January 29, 2008 Share Posted January 29, 2008 From this website- http://www.christianhollumimports.ca/page10.html 527172(RTC1730) ROD BRG STD 2.25L L.ROVER Les. Quote Link to comment Share on other sites More sharing options...
Outrage Posted January 30, 2008 Author Share Posted January 30, 2008 From this website-http://www.christianhollumimports.ca/page10.html Les. Cheers Les/Bowie! Quote Link to comment Share on other sites More sharing options...
Outrage Posted January 30, 2008 Author Share Posted January 30, 2008 Cheers Les/Bowie! Ok chaps, i've now cleaned up the pistons and the markings on the faces are: "90.875" and "Sp 0.12mm" and i'm still non the wiser!? Any ideas if these are oversize pistons? Cheers, Lee Quote Link to comment Share on other sites More sharing options...
Les Henson Posted January 30, 2008 Share Posted January 30, 2008 After managing to steal Bowie's info, it looks like I need to do my own work now Anyway - standard bore size is 3.562 inches in old money and 90.49mil if you're a teenager. Looks like yours are .04 oversize already - someone had to do a heavy rebore. Les. Quote Link to comment Share on other sites More sharing options...
Outrage Posted January 30, 2008 Author Share Posted January 30, 2008 After managing to steal Bowie's info, it looks like I need to do my own work now Anyway - standard bore size is 3.562 inches in old money and 90.49mil if you're a teenager. Looks like yours are .04 oversize already - someone had to do a heavy rebore. Les. That seems a bit worrying 2 me, started thinking I may be chucking away good money if its been rebored several times. Just so i'm sure I need to go for "RTC419340 PISTON RING SET 2.25 & 2.5 DIESEL NA 040"? Cheers, Lee Quote Link to comment Share on other sites More sharing options...
Mark Posted January 30, 2008 Share Posted January 30, 2008 Just out of curiosity, are you pistons oversize too? I have always been under the impression that a rebore will need not only new rings, but also the correct matching pistons too... Mark Quote Link to comment Share on other sites More sharing options...
Outrage Posted January 30, 2008 Author Share Posted January 30, 2008 Just out of curiosity, are you pistons oversize too? I have always been under the impression that a rebore will need not only new rings, but also the correct matching pistons too...Mark Hi Mark, Les's info was based on the sizes taken off my existing pistons, so I think the pistons are correct for the existing 0.40 rebore. i just want to change the rings........ .....unless i've misinterpreted something (which isn't hard 4 me!) Lee Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 30, 2008 Share Posted January 30, 2008 Les? The figures you have there, you must have taken into account the piston -> bore gap somehow... I think? Firstly, I don't know what that is, and because of that I can't see where you get the 40 thou overbore figure from... I'm concerned that if the piston -> bore gap isn't taken into account then it could be on 100 thou overbore already which would be a pretty well abused engine.... Could you let me know how you got there? TIA Quote Link to comment Share on other sites More sharing options...
Les Henson Posted January 30, 2008 Share Posted January 30, 2008 I see what you mean - some pistons have just the diameter on and some have the diameter,and then a second figure, which is the gap there should be between the bore and piston skirt for oil/metal expansion as on this gen piston that is .020 O/S Outrage - It might be best to e-mail Turner Engineering with the info on your piston crown and they will be able to tell you exactly what you have got there. The information I gave you is quite probably incorrect. Les. Quote Link to comment Share on other sites More sharing options...
Outrage Posted January 30, 2008 Author Share Posted January 30, 2008 I see what you mean - some pistons have just the diameter on and some have the diameter,and then a second figure, which is the gap there should be between the bore and piston skirt for oil/metal expansion as on this gen piston that is .020 O/S Outrage - It might be best to e-mail Turner Engineering with the info on your piston crown and they will be able to tell you exactly what you have got there. The information I gave you is quite probably incorrect. Les. This is why i said i'd never mess around with engine internals! I've Emailed Turner Engineering for info and a quote. Cheers, Lee Quote Link to comment Share on other sites More sharing options...
Les Henson Posted January 30, 2008 Share Posted January 30, 2008 I just dropped my block off ( ), and they measured the bores to see what size piston I needed to get, which I did. They then measured the pistons and bored the block out to suit. Although I bought a new head, had the cam bearings fitted and line bored by Turners- I had the block bored by a local company - knowing what I know now - I wish I had got Turners to do the whole job. Although on the plus side - it was 50% cheaper than a V8 I just kept on giving away money Les. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 30, 2008 Share Posted January 30, 2008 Ah thanks Les, much appreciated Lee, just a thought, is the bore lipped badly at the top? If so then you probably need a rebore anyways.... in which case it won't matter what size your current pistons are, as you'll need new ones anyways...... Quote Link to comment Share on other sites More sharing options...
Outrage Posted January 31, 2008 Author Share Posted January 31, 2008 Ah thanks Les, much appreciated Lee, just a thought, is the bore lipped badly at the top? If so then you probably need a rebore anyways.... in which case it won't matter what size your current pistons are, as you'll need new ones anyways...... Hi All, thanks for your useful information and suggestions. Bowie, there is a lip at the top of the bore but it doesn't seem too bad although i must confess, i have nothing to compare it to. I'm thinking of getting new rings, see if the rings plus the revamp of the head clears up the smoke and then call it a day on this engine if not. As has been mentioned prior it's not the best engine in the word and it may be worth seeking out a bigger engine. Price of Pistons plus a rebore plus the time removing the other engine internals, moving the block to the re-borers and then putting the whole lot back together to find i've then got other problems would drive me off my nut! Iv'e had a great quick reply from turners: "Dear Lee, Thank you for your e mail enquiry. From the information supplied it appears your pistons are 020 oversize." they've also quoted me for replacement rings and pistons. Cheers, Lee Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted January 31, 2008 Share Posted January 31, 2008 Good news, and good luck with the rebuild Quote Link to comment Share on other sites More sharing options...
Outrage Posted February 10, 2008 Author Share Posted February 10, 2008 Good news, and good luck with the rebuild Right, new rings purchassed and installed But being a numpty, i can't remember which way round the pistons go in the block!! They've got a V shaped groove on the tops, does the bottom of the V need to point towards the manifold or injector side of the engine?? Thanks, chaps! Lee Quote Link to comment Share on other sites More sharing options...
western Posted February 10, 2008 Share Posted February 10, 2008 bottom of the V [for the valves] needs to be facing the camshaft side [engines right hand side not yours], just checked my workshop manual Quote Link to comment Share on other sites More sharing options...
Outrage Posted February 10, 2008 Author Share Posted February 10, 2008 bottom of the V [for the valves] needs to be facing the camshaft side [engines right hand side not yours], just checked my workshop manual Hi Western, Thanx for that! Will be doing the job 2morrow at work with the aid of the workshop manual, but wanted to check in case it wasn't mentioned in there! Cheers, Lee Quote Link to comment Share on other sites More sharing options...
western Posted February 10, 2008 Share Posted February 10, 2008 anytime take your time & don't rush/read twice & fit once. Quote Link to comment Share on other sites More sharing options...
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