oil leak after change to synthetic

[-=white-zombie=-]

hey all, ive had my vr4 legnum for about a year now its done 190,000kms and when first got it i did an oil flush/change.
i put in semi synth mobil s 10w40, ran all good then 3000kms later changed to 5w30 castrol edge synthetic which ran good also but my lifters seemed abit noisier, so another oil change 3000kms later to the current oil 5w40 shell helix ultra synthetic and some proma mbl8, running nice and quiet and smooth.. and just the other day noticed an oil stain on the garage floor, so i checked under the car and the eng oil sump is all coated in oil (not heaps but a few drips forming) so i took all the side covers off and cleaned all the oil off and took for a long drive and got under again with a torch and can see a small trail of oil running doen under the crank pulley, so i suspec the crank shaft seal is rooted now... i removed all the top covers to make sure it wasnt a rockercover gasket leak and nothing leaking up top....
cambelt/waterpump was done when i first got the car everything was replaced but not camshaft/crank seals so i guess its tear down again and replace them.. now im worried that the synthetic has/is removing any sludge deposits from engine from over the years what if it causes rear main seals to leak, im thinking of changing back to semi-synth to maybe prevent this from happening or should i stick with the synth oil???

[Turbo_Steve]

Or one of your turbos could be failing, and allowing pressure into the oil system, which will cause repeated failures of various seals: but crank seal is a common one.

Unfortunately, the cheapest way of finding this out is to change the crank oil seal....and if it goes again then it's a turbo.

Not sure how viscous 5W40 "ultra" synthetic is.....if it is too thin this can cause issues on a fluid bearing turbo like ours.

[-=white-zombie=-]

pretty sure 0w30 or 5w30 is whats recommended for vr4s so the 5w40 wont have a problem of being too thin... i am also thinking i should replace PCV valve can this pressurise crankcase if too old/ faulty?

[bernmc]

I've heard of this happening when you change to a decent oil. The additives dissolve all the crud and gunge that was helping to maintain a seal, and it starts to leak...

[-=white-zombie=-]

does anyone know if the oil pump seal goes on these motors? cars booked in to get seal replaced in a few days but might get oilpump seal done aswell if thats gone??

[Turbo_Steve]

I've not seen it on here previously: and usually it's a sign of the turbos letting pressure into the oil system, so it might be worth getting them checked out whilst it's having the work done.

[-=white-zombie=-]

if the turbos were leaking pressure in the oil systen wouldnt they be smoking out exhaust aswell? is it just case of seal in turbo gone? mine dont smoke at all and doesnt use any oil, cars always been run at 7psi standard boost prefacelift tiptronic...

[-=white-zombie=-]

got crank seal replaced and no more leaks now.. mechanics said the seal was hardened and good for nothing..

[chris1956]

im not a mechanic but i think mine is leaking from the same place
is it a big job what is involved

[pitslayer]

im not a mechanic but i think mine is leaking from the same place
is it a big job what is involved

Not sure which way it works on the VR4 as I have not done it but it will involve the removal of either the gearbox or the engine to replace what will probably be a £3 seal



ETA: hmmmm would need one of the other VR4 owners to confirm but camskill are showing this crank shaft oil seal
http://camskill.co.uk/products.php?plid=m22b0s1399p9758

Which is on the cambelt side, so at a guess you will need this oil seal, new cambelt kit, if it hasnt been done, do the water pump aswell, so you would be looking at around £600 job or so, but thats only what I can gather from the information I already know