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.
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.
