CharlesElliott Posted January 6, 2016 Share Posted January 6, 2016 Spoke to the engine builder today (approved engine builder for our race series). My engine had suffered from oil loss, but upon stripping it down there wasn't really any oil damage....however, it did need:- two new (forged and machined) pistons due to gudgeon pin migration; one piston was no longer held by the gudgeon pin on both sides. one new rod due to the above, weighted to the other four.- two replacement liners due to the above. One had a step in it and one had a big score in it from the flappy piston.- replacement crank due to the flappy piston wearing it.- replacement camshaft due to crack in existing camshaft. new timing sprocket as existing one was loose on cracked camshaft.- replacement clutch plateand then all the other 'standard' things during a rebuild; new rings, new big end bearings, big end bolts, inlet and exhaust valves etc.120bhp here I come!Charles Link to comment Share on other sites More sharing options...
Superwhite R283 Posted January 6, 2016 Share Posted January 6, 2016 That's harsh Link to comment Share on other sites More sharing options...
DJ. Posted January 6, 2016 Share Posted January 6, 2016 At least you got to it before it went really wrong when the cam/sprocket gave way I suppose Link to comment Share on other sites More sharing options...
Grubbster Posted January 6, 2016 Share Posted January 6, 2016 When was last time it was rebuilt Charles? Link to comment Share on other sites More sharing options...
CharlesElliott Posted January 6, 2016 Author Share Posted January 6, 2016 What a gudgeon pin fitting shouldn't look like. Note the gap on the right hand side where the pin has moved across to the left through the rod and no longer makes contact with the piston body. Link to comment Share on other sites More sharing options...
CharlesElliott Posted January 6, 2016 Author Share Posted January 6, 2016 Top end - September 2012Bottom end - April 2010 (new pistons and rods) Link to comment Share on other sites More sharing options...
Area Representative Nick Chan Posted January 7, 2016 Area Representative Share Posted January 7, 2016 There was a £5k rebuild invoice in the file of one of my previous cars for a 120 BHP K series engine. It was carried out by Minister and a belting engine Link to comment Share on other sites More sharing options...
Slipper man Posted January 7, 2016 Share Posted January 7, 2016 Good grief! Minister only charged me £6,500 for a new R500 engine! That was in my car for 7 years and 7,500 circuit miles before I removed it, just because I thought I was playing with fire going so far beyond the 3,000 mile recommended rebuild time. The engine was just fine as far as I could tell. One day i will strip it and see what the innards look like. Link to comment Share on other sites More sharing options...
OliverSedlacek Posted January 7, 2016 Share Posted January 7, 2016 Youch, but at least you caught it before the piston went completely AWOL. That would have destroyed pretty much all of it! Link to comment Share on other sites More sharing options...
oilyhands Posted January 7, 2016 Share Posted January 7, 2016 Migrating pins are common when trying to reuse the interference fit on a rod, forged Pistons should be fitted fully floating with the rod small ends bushed or honed and the pins retained with cirlcips. Trying to reuse the interference fit is unsafe.Oily Link to comment Share on other sites More sharing options...
CharlesElliott Posted January 7, 2016 Author Share Posted January 7, 2016 Hi DaveI'm sure you are right. When originally fitted in 2010, they should have been brand new rods and pistons (but I'm not convinced). Charles Link to comment Share on other sites More sharing options...
oilyhands Posted January 7, 2016 Share Posted January 7, 2016 Rods were only available from the factory as assemblies with stock pistons already fitted, so it would be necessary to remove the old pistons before fitting the forged ones. It is this removal that compromises the interference fit. Once the interference fit has been used it can't safely be reused. It's highly likely that the original rods were reused.Oily Link to comment Share on other sites More sharing options...
CharlesElliott Posted January 7, 2016 Author Share Posted January 7, 2016 Thanks Dave, I may have misunderstood what I was getting in 2010.I can at least ask some more educated questions about the current rebuild (different builder to the 2010 builder).Charles Link to comment Share on other sites More sharing options...
Wrightpayne Posted January 8, 2016 Share Posted January 8, 2016 I recall from David Vizard's book on tuning the A series he recommended teflon plugs in the ends of the gudgeon pins so if they did move the bore / block wouldn't get gouged.Ian Link to comment Share on other sites More sharing options...
oilyhands Posted January 8, 2016 Share Posted January 8, 2016 They were an alternative to circlips and are only used when the pin is fully floating in the small end. If the pin started to move against the plug with an interference fit it would likely mash the plug.Oily Link to comment Share on other sites More sharing options...
OliverSedlacek Posted January 8, 2016 Share Posted January 8, 2016 The PTFE plugs described by the esteemed Mr Vizard are an alternative to circlips, and not a 'belt and braces' solution if your interference fit is no longer tight enough for the job. I think they were popular with engine builders across the pond, where they do things a bit differently. They would save on having to machine a circlip groove into the piston if you were going from interference fit to fully floating. Link to comment Share on other sites More sharing options...
charlie_pank Posted January 12, 2016 Share Posted January 12, 2016 that's an expensive non-upgrade. I appreciate you have to go through the approved builder for the sealed-engine race series, but I can't help noting that a whole 'new' R1 engine is 180hp, about 60kg lighter and about £1,000! Link to comment Share on other sites More sharing options...
CharlesElliott Posted January 12, 2016 Author Share Posted January 12, 2016 You can buy an engine on eBay for £250 or whatever, but you still have to change the sump and ancillaries, still need to put in forged pistons (say £1000), so it's expensive to get a race engine in the first place - even if it is only a 1.6.Of course, following the spirit of race budgeting I have no idea how much it will cost and haven't asked - you only find that out once you have had all the work done and are committed. Exactly the same with my chassis; only asked Bruce to price it up when he rang to told me it was ready to collect Link to comment Share on other sites More sharing options...
Steveh7 Posted June 27, 2016 Share Posted June 27, 2016 Hi CharlesMy car suddenly started to use half a litre of oil after each 20 min session this weekend and after speaking with one of the approved engine builders and doing a search on here he suggested the same issue as you have described above :( I didn't discuss costs on the phone and the car hasn't yet gone in for a proper diagnosis however it would be really useful to gain feedback on your experience.Overall are you happy with the work and could you provide an indication of ball park figures for the work you had done....basically just looking to calculate when I can afford to race again...... Steve Link to comment Share on other sites More sharing options...
CharlesElliott Posted June 27, 2016 Author Share Posted June 27, 2016 Steve - drop me an email and I'll be happy to let you have the details. Charles Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now