[mike1967]

Thank you

tend to find them with 80k on the clock 175psi on cold engine is fairly good, the turbo engines tend to be higher as direct injection compression ratio higher as well, its worth doing a cold engine test and an hot engine test see what happens with it, have seen weak rings loose compression under heat loads, also if have low reading put a syringe full of engine oil in the plug holes a retest, if compression jumps up a lot then piston rings are worn out, if stay same but still low then its a head issue or a hole in a piston, either way its head off and have a look, thats how i tend to check them these days only gear you need is compression tester.. when doing leak down with compressor takes more time and still gets same result,

 

[mike1967]

i have done a compression test on the mini one that failed the emissions test and here are my findings

1st psi figure with hot engine 2nd psi figure with hot engine with syringe of oil

Cylinder number 1, 125 psi 150 psi
Cylinder number 2, 127 psi 152 psi
Cylinder number 3, 126 psi 152 psi
Cylinder number 4, 126 psi 152 psi

does the engine require piston rings or valve stem oil seals or both.

bought the car needing timing chain kit and head gasket. the engine runs smooth after installing an new head gasket (pressure test on head was ok ) so do you think valve stem oil seals will solve this issue as they may have become cooked with head and timing issue

little bit of blow past by looks of that,, but not bad really all even might find a good service and seafoam the oil and bores might increase them, when engine running and id hot how much vapour comes out of oil filler cap hole when removed,, if a lot then oil change and seafoam it give it a good run thats what i would try first off,, how many miles the engine done

 

[mike1967]

Engine has done about 115,000 miles.
Dropped engine oil to do the chain then dropped and replaced when worn oil pump was changed so oil is clean.
Was annoyed with local engine shop as when I asked him to change the valve stem seals he said they don't go on these.
What does seafoam do.
With the compression readings as they are would the blue smoke indicate seals

seafoam cleans the carbon off the piston rings and recesses if gummed up could be holding off sides of bores as such, if add to fuel tank it will whit smoke on petrol engines until its out of the system but dose clean it all out, also if its in the cat and exhaust will do the same would need to take car for a 20 mile run to clear it on that level. best treatment on a petrol engine is spray a tead in each bore leave it over night to soak, and stick can in engine oil run it for 50 miles then change oil it will clean all carbon and dirt out of the whole engine

 

[mike1967]

Are there specific types of seafoam I need.

Do you think it could be the valve stem seals

https://www.ebay.co.uk/itm/SEA-FOAM...ck-SF16-SS14/252949392944?epid=899626704&hash=item3ae4f56e30:g:YNIAAOSwaEhZILG4
above link double pack one is a inlet and spray type, other is pour in oil
could be stem seals without removing it hard to tell

 

[mike1967]

Thanks for that. I have spoke to a local mini specialist who has told me he has made a tool that can be used to remove and replace the valve stem oil seals for £200 in labour. I have the valve stem oil seals from a headset I used.
I worked out that the time I would need to remove the head and get a specialist to then change the seals plus a new head gaskets and bolts would far exceed the £200 quoted
Just a bit worried if the seals are changed but the issue is still there.
I suppose once that's done I can run some seafoam through it

would run seafoam through before as it might be all the problem a little bit of carbon somewhere allowing oil to pass, cheaper way forward might save £200

 

[mike1967]

exhaust leak might effect the down stream 02 sensor but wont cause oil burning blue smoke, maybe the rocker cover pcv valve is faulty allowing crankcase oil in to the inlet.

 

[mike1967]

Are they cleanable or replaceable

repairable i believe have a diagram with a spring in them. lock at breather pipe to rocker box notice a plastics square as such that clips on to rocker only trouble is plastic gets hard and snaps off the lugs when try to remove them if get to handy with them,

 

[mike1967]

Well some good news at last after the car had lots of blue smoke and had failed the mot.
Took it to the local mini specialist.
He has made a tool to remove and replace the valve stem oil seals with the head in place
He did the job on Friday and the car past the mot this morning.

He is of the same view as mike1967. When these engines are low on oil it starts a chain of events. First the chain stretches throwing the timing out this causes overheating and makes the valve stems hard and creates blue smoke
Also the excess fuel damages the o2 sensors and the cat
If left long enough the chain jumps and damages the valves
Can't stress enough keep your oil at the correct level

its nice when someone else also works out the chain of events... ironically all those chain of events could of been avoided by past owners and laziness with doing weekly checks on the fluids from my experience of some peoples reaction when told yes you screwed your engine just because of it,

 

[mike1967]

I think it's a combination of lazy owners not checking the oil but more so on the dealerships and the manufactures telling customers that service intervals are longer due to long life oil. This is a selling point as it reduces the cost of car ownership.
But by doing this owners believe that oil doesn't need checking between servicing.

thats part of it for sure, the other part of that conversation when a new car buyer is sat there being preached to about how good this car is and service costs is the final nail in the coffin, "YES THIS CAR HAS A TIMING CHAIN SO NO TIMING BELT CHANGES ITS LIFE OF CAR JUST DRIVE AND FORGET IT" all said by a salesman who has no mechanical knowledge and who just wants the bonus to sell that car to you, then there's the lease cars and ex hire cars that are sold as one owner fully serviced cars,,, all this is every car on the road most if not all cars 2006 onward's suffer from same issues lost count of the vag group engines that fail due to oil and dpf or timing chains so its not just bmw mini its all of them.

 

[mike1967]

Now the car has passed it's emission after valve stem have been replaced the mechanic said it needs a good run to clear all the oil residue from the manifold through to the downstream sensor
Would a bottle of cataclean or seafoam be any help cleaning it out along with a good run on the motorway

thats what i tend to do with them the cataclean works by raising the temperature in the combustion chamber plus additive weaken carbon build ups, the oil is the issue as seafoam will help to remove this to a point, i would use inlet spray seafoam then get spray in while engine is reving at 3000revs you will have loads of white smoke while doing this when its in middle of being really thick smoke if it will (ie some inlets dont allow all the seafaom to go to inlet points right away)
what i do is there is a red hard straw that comes with the can of inlet spray i feed this in to inlet throttlebody ie air cleaner off and angle it towards the inlet ports when spraying it... so have loads pf white smoke going on proves its well in to the cat etc,,, they have 30 seconds to 60 seconds of this while still spraying switch engine off and leave the car to soak this will coat the cat and all the inlet and exhaust and inside engine,
then after leaving it for 24 hours plus when start car instantly start it and hold at 2000 revs mini 3000 max until car is up to running temp then go take it for a good hard run with cataclean in the fuel tank ie mixed on no more than 1/4 tank of petrol,, thats what i have done for years some it totally cures and some are so far clogged with oil residue that they will never come back,,
the key is that first drive 20-40 miles over 3000 revs as much as can to get the cat so hot it burns off the oil residue,, its bruttle but works a lot of the time,, just make sure oil and water levels are correct and no other faults,, you might get fault codes for cat and 02 sensors at first if so its just the crap burning off or the ecu getting to grips with all the changes

 

[mike1967]

dont need to leave fuel line on fuel rail is fine,, or can pop rear seat out and undo the metal round plate on floor to pull the electric connector off the top of in tank fuel pump