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Discussion Starter · #1 ·
Hi
Apologies for very long post but wanted to explain steps taken so far.

My daughters mini developed loss of power on way home for Christmas, she managed to continue driving to get home.
I diagnosed zero compression on the cylinder furthest away from gearbox (Number 1?) and removed head to find one exhaust valve damaged .
I have had the head skimmed, replaced the exhaust valve, re-lapped all valves, replaced all valve guide seals and fitted new timing chain. I also replaced the rocker cover with a patent one after reading lots of comments about pcv valve failure and the car used to use what i would call an excessive amount of oil before this issue.
Reassembled and engine seemed to start fine and run okay, but with a code P3041 camshaft position A which I think is due to the cheap timing tool I used, have now brought Laser version to re-time (not done yet).

However when I took it for a test run there seemed to be excessive oil smoke from the exhaust particularly when engine braking down hill and then applying the throttle and it has used oil even only having covered small number of miles. Also when parked up and revving on and off throttle continually there is oil smoke.
I have since done lost of research (particularly mike 1967 posts) and realised that I should have replaced piston rings at the same time but I don't think the amount of smoke I am seeing would be due to oil control rings or that I managed to incorrectly fit/ damage the valve guide seals.

To try and see if it was a breathing/ pcv issue or rings / valve guide seals, I disconnected and bunged the breather hose to inlet manifold and ran a pipe from rocker cover to a plastic bottle. Then took it a test run and there was no smoke from the exhaust even on overrun and throttle back on and there was no oil in the plastic bottle although lots of oily fumes even when on tick over. This seemed to indicate a possible Pcv valve issue. I carefully manged to remove top cover from the rocker cover and inspected the pcv diaphragm and spring. All seemed fine so reconnected breather hose, and when engine is ticking over the diaphragm is pulled down and raises when revs increased. Strangely though when ticking over there is a vacuum in rocker cover. I am not sure if this is normal, I can tell this by trying to remove oil filler cap on tick over. I have also now removed inlet manifold to check for any cracks in the breather pipe and it's fine, but the manifold contains an excessive amount of oil.

I am not sure what to do next and would appreciate any advice. For info engine has covered 95,000 miles.
 

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when they smoke due to oil in pcv pipe and inlet its normally down to piston ring blow past , also on over run as crankcase pressure gets to high that is one level, over level is when do valve stem seals must lag them in oil when doing them, also when push valves through the oil seals you are meant to use protector over the end of valve stem to avoid hurting the rubber lips on stem seals,, that said i get around that by slowly and gentle rotate the valve as it goes past the stem seals to avoid damage the seals , i also use engine builders grease to avoid such issues,
 

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I when I replaced valve stem seal I wrapped a piece of insulating tape over end and groves along with lots of oil.
Looks like a ring change then.
Thanks for the reply.
when do rings must use a 3 piece ring for oil rings so much better , i've started using
a new ring set made by FAI on paper should be better than sm rs1600 rings i normally use ,

Font Material property Rectangle Gas Magenta

Rim Gas Nickel Automotive wheel system Metal


White Automotive tire Light Motor vehicle Wheel

below sm rs1600 rings
Font Gas Event Electric blue Transparency
 

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Discussion Starter · #5 ·
@mike1967
Purchased the FAI rings and ready to fit along with FAI big end shells.

Just wondering what position you set all the ring gaps on the pistons. Looking at the engine from the front of the car. Top ring 2 o clock, second ring 6 o clock and bottom ring at 10 o clock? Do you line up the 3 parts of the oil control ring in the same position?

Also purchased new oil pump chain and gears. When torqueing the oil pump sprocket do you just lock crankshaft and torque using chain as lock?
 

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@mike1967
Purchased the FAI rings and ready to fit along with FAI big end shells.

Just wondering what position you set all the ring gaps on the pistons. Looking at the engine from the front of the car. Top ring 2 o clock, second ring 6 o clock and bottom ring at 10 o clock? Do you line up the 3 parts of the oil control ring in the same position?

Also purchased new oil pump chain and gears. When torqueing the oil pump sprocket do you just lock crankshaft and torque using chain as lock?
i set them 9 o clock to to 3 o'clock on top two rings this gives more ring arear and no risks of the ring edges digging in the bores,, also when you look at rings the black middle ring has a rounded edge to it that edge faces downwards towards piston skirt, the top ring has a faint dot on it that faces upwards,, the SM rs1600 i was using came in a east packet and was clearly marked TOP on the rings,, the oil rings i set 180 degrees apart from each other and they dont matter where they sit so much ,
 
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