MINI Cooper Forum banner

1 - 20 of 42 Posts

·
Registered
Joined
·
6,863 Posts
Discussion Starter #1
found a little project 2007 mini cooper s JCW spares repair 60.000 miles on it full service history very nice car, this guy paid a lot of money for it 9 months ago, and one day coming home from work it went bang started smoking really bad and running on 3 cylinders etc, he took car to garage who informed him the turbo had failed and had taken out the engine etc,,,, so after a full day and a proper diagnostics checks found number 4 cylinder had no compression dry test and after a wet test it went up to 40psi so piston issue,,, so striped the car when i removed the turbo checked it found there to be nothing wrong with it,, when removed the cat found it had a handful of black chucks of cat honey comb melted in the pre cat end closest to turbo and also found it had oil burning deposits on all piston and on back of the valves the inlet valves had bad build up of carbon as they do this was part of why it destroyed its number 4 piston where unburnt intermittent firing of the fuel that had washed down between the piston rings etc and when ignites blows them apart also found the timing chain to be stretched two teeth out,, so this engine had no chance really,, so the fix is new pistons and rings new big bearings head gasket and bolts stem seals etc the cause of all this started with inlet valves and carbon holding them off the seats and washed the bore,, also retarded timing over heated valve stem seals and oil blocked the cat and unburnt fuel also added to it and melted the cat,
once ts back together its going to be decat'd and put on rollers see what can be had from it,
 

Attachments

·
Registered
Joined
·
995 Posts
Similar happen to me on one of the piston last year when I took the car in for timing chain service and walnut blast :ROFLMAO:, blow out black smoke out of the exhaust.
 

·
Registered
Joined
·
6,863 Posts
Discussion Starter #3
Similar happen to me on one of the piston last year when I took the car in for timing chain service and walnut blast :ROFLMAO:, blow out black smoke out of the exhaust.
its the mixture of oil burning and petrol and add the timing chain also retarding it turns the cat in to a furnace and melting it, have seen a fair few like it easy way to tell is on compression test do a wet test as well if compression jumps up its piston and if dont then it valve issue as a rule, i'll stick a set of pistons in and put scotch brite pads on my hone tool as the stones are to rough on the bores, i got all the valves out so these will be cleaned and polished and new stem seals little tip for anyone when installing stem seals just add a tiny bit of well seal on the part they clip to on the head and then use socket and hammer and tap them home, have seen them leak oil past if dont from the bases, then rest of the engine is perfect,,
 

·
Registered
Joined
·
6,863 Posts
Discussion Starter #4
little update today finished stripping it found the rest of piston oil control rings were cracked so has been drinking oil as last owner said,, also cut the cat apart and taken some pics of how melted and blocked it was,, all 4 pistons have signs of being washed with petrol down the sides common when inlet valves get gummed up also the blocked cat was the finishing blow ie back pressure and heat etc surprise it even ran to be honest,, word of warning to all out there who there car uses a lot of oil and smokes and has not had a timing chain replaced ie this car was 58.000 miles and to be honest it needed doing around 40k on this to have stood a chance of avoiding this out come...
today i cleaned all valves and head lapped all valves in all ready for new parts when they arrive, i also scotchbrite pads on hone tool on bores and all 4 look like new , also turned pistons 90 degrees to check if oral bores as a guide all near perfect so with be a really good engine when done, no wear on crankshaft fitting new big ends bearings and new conrod bolts as stretch type will add red locktight to threads,,
 

Attachments

·
Registered
Joined
·
6,863 Posts
Discussion Starter #6
Is that CAT from the downpipe or further down to the back exhaust?
thats the down pipe one i cut the top around the weld so can re-weld back up along the factory weld so by time welded back wont be able to tell its decat now, only thing i would say to anyone with a oil burner with some miles on it and having head off anyway its worth the extra £55 for ring set, £35 for bigends £15 from bmw conrod bolts use red thread lock on them as well i found all the oil control rings to be cracked, i feel this was from retarded running due to chain 2 teeth out the oil blocked the cat cause a furnace effect rings could not cope with extra heat the oil rings are no more that 1.2mm thick each one there are two as such but install as one ring if that makes sense,, also the bores were glazed from oil burning so i use scotchbrite pads cable tied to the arms of the hone tool this is just enough to remove the glaze and dont hurt the low friction bores , i have used the stone hone tool once before on the bores and never got a good result it used oil like hell after,, this is why i always se seafoam engine flush on my stuff it stops carbon build up on the rings as carbon build up also hurts the rings,
 

·
Registered
Joined
·
995 Posts
Thanks mike1967.

I'll also probasbly need a new sports cat downpipe for mine.

Does de-catting the downpipe not fail MOT unless the tester can fiddle with the test?
 

·
Registered
Joined
·
6,863 Posts
Discussion Starter #8
its is mot fail for sure, but if car is mapped correctly where on fast idle the fuelling is leaned it will reduce the output from exhaust hence why its a must have mapped out bit must keep the 02 sensors running as part of the test is lamda readings, so by keeping the stock filter case its possible to set it up so it dont stand out if that makes sense. also where car gets mot's makes a difference ie if use big garages or companys then they love failing stuff for the slightest reasons, if do have it mapped out talk with mapping company about who they use mot wise etc,, or fit a sports cat thats got smaller honeycombe thats does have a effect of altering the CO and co2 levels,, but if mapped for pops and bangs then decat is only way as the pops and bangs will blow the cat apart
 

·
Registered
Joined
·
6,863 Posts
Discussion Starter #9
added bit is when mapped we lean the engine out on fast idle running and also map a difference in to pre and post 02 sensors readings ie fouls ecu to thinking a filter is there still etc so when mot'd the screen asks for 2200revs at this pint the ecu is set to lean out the readings, it does lose a bit of low down power by doing it but makes the top end more of a surprise when done right
 

·
Registered
Joined
·
6,863 Posts
Discussion Starter #10
today got bottom end all back together pistons in and new piston rings i used the latest spec piston rings as in the n18 and other bmw cars the oil ring is a vamped one ie made of plastic so never hone the bores i only use scotchbrite on hone tool just take glaze off with put leaving to rough as to rough will wear away the plastic oil rings on bottom of pistons,, some pics below
i use engine oil mixted with wyns oil addive as in pics this helps keep oil on all parts and makes fitting pistons easier,
also gudgeon pin circlip a little tip use molgrips to hold as per the pic and then use a screw driver to push the rest of clip in to its groove,.
also when fitting rings never try to stretch them to fit, always put one end in its groove then rotate it in to the rest of the groove as such, the oil ring fit that same way then add the spring in it groove, i always set the top two compression rings 180 degrees apart on their open parts ,, use loads of oil when fitting them, i also add thread lock to the big bearings to hold them in place when fitting pistons, i also when doing this do the two bolts up on end caps before fitting them to car and let set for 30 minutes, when fitting pistons never force them or hit them always tap the ring tool level to the liner, also remember the piston go one way only and so does the big end caps,,, if can see any lines where they join then they are wrong way round and bad will destroy its self within 10 minutes like that,
conrod bolts must be renewed i always use thread lock on them they are stretch bolts £1.09 each from ocean bmw
i also stripped oil pump cleaned it checked it pics below no damage perfect
 

Attachments

·
Registered
Joined
·
6,863 Posts
Discussion Starter #11
so now in to the cylinder all valves cleaned and head cleaned all valves lapped it so seats all good,,, so when i fit the valve stem seals i always rub well seal sealant on the bottom part that is then tapped donw with a socket to ensure they seal from the bottom,, i have seen people fit these and not bother and get oil burning on over run oil can sometime leak from the bottom edge so to be safe i always do this pic below for ref,
then when i fit each valve i cover in oil and wyns additive and also the seal and guide plenty of oil i then rotate the valve while very gently pushing it past the rubber seal failure to do this can damage the rubber seals,, this its the fun part fitting the collets back in to the valve stem to hold spring hat etc,, what i use is a cheap ebay valve tool that is threaded so got better control on how far i compress the spring ie only just enough to get collets in to the top grooves,, i also use vaseline jelly and a small scratching tool ie the collet stick to the tool then sticks to the valve top ans is easy to stick to it they poke it around to get each one in to their grooves then once in slowly un do compression tool job done takes 5 minutes per valve star to finish pics below for ref
 

Attachments

·
Registered
Joined
·
6,863 Posts
Discussion Starter #14
You're a quick worker ;).
just done so many its second nature now think i'm 18 hours in so far prob got another 10 ish to go by time map it and run it up for a few hours on idle on first start start up is how i tend treat them. not that bad engines to be honest what harms them is people who are ignorant with checking the oil and early oil changes etc most of that is when the were new really as most think a new car should never use any oil,, but with pcv systems and low friction tech stuff the all do, i always check oil on my cars at first every few days then as i work out what it uses and work out weekly or mileages to in my head,, another day tomorrow should get it nearly done but still need to weld the cat back together then map it monday tuesday ish i would think,, might need to buy a couple new 02 sensors but going to try and bring them back again first with cleaning and cataclean and a 3k 20 mile run might bring them back again
 

·
Registered
Joined
·
6,863 Posts
Discussion Starter #15 (Edited)
so today was another special day of the parts gods messing with my world, goes like this when I ordered the head set and bolt set I found the correct kits on a seller who i use a lot on ebay they are engine builders as well so get good parts that way, then messaged me to tell me the kit I ordered was wrong one so I ordered the one they told was the correct one,, so today i got all the way of finishing head and cleaned both surfaces put the gasket on the block dropped head on,, then opened the box of head bolts bugger they are wrong twice the size prob N18 bolts not n14 so thats me stopped until i get bolts grrrr.
did finish head and put some pics up cam shafts all the bolted caps are number and MUST GO BACK SAME WAY, also pics of how i keep head off bench while installing camshafts and camlocks so dont bend valves when rotating them and resting head on valve side ie 4 old head bolts and 4 sockets as spacers, also in pics a must do job squeeze the oil out of the lifters this also helps clean them out.. also in pics shows the first journal where the vanos sprocket oil rings live these were ok, i also cleaned both head and block surfaces with brake cleaner and clean wrags until spotless grease free i also clean out all bolt holes in block ie no oil of water in them a must do job before fitting the head bolts back,
 

Attachments

·
Registered
Joined
·
6,863 Posts
Discussion Starter #16
update to the head bolts was a picking order so sent totally wrong bolts from god knows what engine give them their due have next day'd me the right ones and a postage slip to return wrong ones so hopefully by end of week will be all back together and mapped as well ie rolling road runs will put up the results for others, or if interested in engine work or maps etc in my signature for contact, just completed a r53 for a guy and got 233bhp at front wheels with a fast road cam and some other stuff ie top engine rebuild and t chain etc
 

·
Registered
Joined
·
6,863 Posts
Discussion Starter #17
so today put the head on torqued it down ie 40nm plus 90 plus 90 degrees in pics below you will notice blue dots ie thread lock ie leave a dot every time i add 90 degrees to that bolt so buy the end of the job there will be 2 blue dots for each bolts and then i know for sure each bolt has had 180 degrees of stretch i promise you not doing that one day will catch you out ie over stretch or under stretch a bolts etc,,
also in pics shows dipstick little tip blob sealer on the o-ring before installing it, also blob sealer on the rocker cover surface in corners water pump end
then i fitted timing chain kit pics of all new genuine bolts from bmw they were cheap £3.00 each for cam bolts and bottom one was £6 the new oil seal was £25 genuine one all bolts lightly oil and fitted, bottom crank bolt 40nm plus 120 degrees,, the cam bolts inlet 20nm plus 180 degrees and the exhaust cam 20nm plus 120 degress, i set timing on this the first time ie after setting it rotated engines 4 times relocked and locks fell in to place perfect,,, i also put pics up below of timing chain guides and how to slot together the centre pivot very important this is done correctly that the pivot side view looks like the one in the pics,, so all timed up sump back on have then filled with engine oil and without the plugs in cranked the engine over about 10 times ie finger on start button until it cuts off repeat this until oil gets up to the turbo and camshafts before starting it as with new bearings on crankshaft and pistons etc you need oil to be there before running it, tomorrow will finish it off them map it and delete the cat form software job done ho yes and run it it in for a few hundred miles before dropping a big power map on it ,, would think 230 to 260 bhp maybe
 

Attachments

·
Registered
Joined
·
6,863 Posts
Discussion Starter #18
so today got turbo pipe fitted it and before sticking front all back on ran the car up, ie started first time once fuel primed and the normal smokey as had so much oil in the exhaust and used a lot in the rebuilding of engine this cleared in 10 minutes or so, i then just let it idle for well over hour and half while diagnostics is plugged in and live data running like to know whats going on from the off just in case something is wrong , i also on first start up have the oil filler cap off and check oil is coming to top of engine and it is i also cracked off the water top pipe to turbo let any air out, i also unscrew the bleed plastic screw on top of the thermostat housing let any air out of there as well, then just let it build heat while watching the temps on live data, i also watch the smooth running and cylinder misfire options for all 4 cylinders as you can see on below pics all are the same and all perfect, also it shows the injectors duty's number 1 is slightly worn but will prob clean up with can of seafoam in fuel tank and some good runs,, also i check as the pic below shown vanos actual and prescribed positions and you can see are perfect think 21 degrees matched or within 1 degree is perfect to be honest. ha ha not bad when it took me 15 minutes to set chain up etc and cheated never used the dummy tensioner lent my kit to a mate and he cant find at mo,,, so there you go its poss to set them up without it just need to do the bottom crank bolt up first and also do the stretch part at same time then time the engine from the camshaft sprockets with spring tensioner fully in, ie set at 20nm rotate 4 times then re-lock if locks drop on then its fine, also must hold both cam shafts with a 27mm spanner and must not let turn when stretching the bolts,
also done a compression test on hot got 190psi on all 4 the same after a hour running so would say rings went well there no crankcase pressure either and not chuffing from the oil filler,, also put my ear to sump and sounds perfect no rattles etc,,, still have a few cam lifters slight tapping but as the hour went by got nearly silent now as the oil gets thin with heat and pushes them out etc, one thing have noticed got a high pressure fuel pump fault code came up after first 20 minutes but when cleared not came back but time will tell if there is further issues, all water pipes are fairly soft when car is at 90c and both rad pipes were nice and hot etc, when switched off could hear the turbo aux coolant pump working i checked it was pumping by loosen off top coolant union on turbo and water sprayed out so, so far all looks on track,, all left to do now is put front back on it and test drive etc them map it and delete software decat,
when i was rebuilding it i got new piston ring set same rings used in later n18 and b series bmw car ie latest spec piston rings, these are black sprung steal compression rings and very odd looking oil control rings that are plastic carbon stuff where the old rings were steal very thin metal rings in 3 pieces the new oil ring is one piece with a spring around it as such,, glad never honed the bores ie used scotchbrite just to de=glaze on hone tool as would think if bore were to course it would wear them away in no time..
 

Attachments

·
Registered
Joined
·
6,863 Posts
Discussion Starter #20
Running it up without the front end built up.makes so much sense.
i know i do try and learn my lessons lol, i even try'd to use the old oil feed pipe for turbo i never moved it or anything put cat back on and heat shields etc and it leaked, ordered a bmw one £54 lighter but at least with how in bits this car has been it fired up and so far runs perfect no nasty noises etc and live data is all reading good, but i suspect its got a high pressure fuel pump fault maybe need to look in to that tomorrow just my luck to need one i bet, or might be the low pressure feed pump in sender unit in the fuel tank might be getting worn out, not that good for a 60.000 miles car if it is
 
1 - 20 of 42 Posts
Top