Identify part leaking oil

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I checked underneath earlier car has not been driven since yesterday. There were no new signs of oil leaking on the pipe

Only option is to attempt to thorougly clean the area and monitor
Clean all the hydraulic lines then return to them after a run with a white rag or kitchen roll and clean them again noting where any stains are from.
Where the rubber goes into the steel joint the white rubber clamp has split, could this cause it to leak?
Two things to do here. Detach the hose from the clamp and see what it looks like underneath it. And, look for another hose with similar arrangement and compare.
Dont think you can buy them separately, was thinking of using a small jubiliee clip?
They will be available separately. When you identify the line, consider replacing the corresponding other one at the same time. If the rubber is that far gone to leak it may be breaking up internally. PAS lines doing that can deposit bits of rubber in the valves.
If hose is steel braided (probable) then Jubilee clip wont work - only crimping is strong enough. If it isn't braided - and you can pinch it closed with your fingertips (with the engine off) - then a Jubilee might work but replacing the line(s) would be much better.
Do you think its okay to continue to drive the car?
I'd be cautious. A mere weep isn't a major concern right now but fluid is being lost from whichever system the line serves.
Leaks don't cure themselves and there's always a risk of complete failure. If that line is a trans cooler line and it empties the contents of the transmission not only will it wreck the trans before you can shut it all down, oil dumped on the road surface wont do much for the rear tyres' adhesion.
 
Clean all the hydraulic lines then return to them after a run with a white rag or kitchen roll and clean them again noting where any stains are from.

Two things to do here. Detach the hose from the clamp and see what it looks like underneath it. And, look for another hose with similar arrangement and compare.

They will be available separately. When you identify the line, consider replacing the corresponding other one at the same time. If the rubber is that far gone to leak it may be breaking up internally. PAS lines doing that can deposit bits of rubber in the valves.
If hose is steel braided (probable) then Jubilee clip wont work - only crimping is strong enough. If it isn't braided - and you can pinch it closed with your fingertips (with the engine off) - then a Jubilee might work but replacing the line(s) would be much better.

I'd be cautious. A mere weep isn't a major concern right now but fluid is being lost from whichever system the line serves.
Leaks don't cure themselves and there's always a risk of complete failure. If that line is a trans cooler line and it empties the contents of the transmission not only will it wreck the trans before you can shut it all down, oil dumped on the road surface wont do much for the rear tyres' adhesion.

Will give the area a clean with brake cleaner, although some areas are difficult to reach

For the sake of £13 I may go ahead and replace the banjo bolt, seal and o ring

Other sources of the leak could also be:
air intake hose
cylinder head cover gasket
oil filter housing

Will inspect the above areas and report back

I'll also remove the clamp and inspect


Decided not to drive the vehicle, best to be safe!

Thanks
 
Will give the area a clean with brake cleaner, although some areas are difficult to reach
Skip the brake cleaner. You only need existing wet accumulations removed. Dry is as important as clean.
For the sake of £13 I may go ahead and replace the banjo bolt, seal and o ring
Your call - but if it aint broke, don't fix it!
Other sources of the leak could also be:
air intake hose
cylinder head cover gasket
oil filter housing
It can be a PITA tracing a leak when the fluid is picked up in the airstream and deposited everywhere.
Prioritise a leaking hose which can deplete a reservoir and cause mechanical damage - watch fluid levels.
Will inspect the above areas and report back

I'll also remove the clamp and inspect
Any sign of leakage from that pipe in that join could be the mystery solved.
Decided not to drive the vehicle, best to be safe!
As above - pressurised lines are the concern. Other leaks are merely a messy inconvenience.
 
@Bellow

Car has stood for a few days no new signs of oil leak present on the pipe or anywhere else

Given that that oil residue was found on top of the alternator and above the gearbox it could only point to the oil feed line being the culprit as this was the highest point I could see signs of oil residue and the surrounding area

So went ahead replaced the banjo bolt, 2 washers and o ring

The banjo bolt was the old version, the revised version looks a little different.

Looking at the original o ring, it did look worn, alot more thinner and brittle compared to the new one

Hopefully this has cured the issue. I havent put the undertrays on yet will give it a few days/weeks and monitor.
 
@Bellow

It's been a few weeks since I replaced the banjo bolt, o ring and sealing rings, thought I'd go and check underneath before putting the undertrays back on but lo and behold there is still a leak, I'm at a loss as to what it could be it's definitely engine oil

Could it be the sump? or the seal between the transmission?

But what throws me is there is signs of oil leak above those areas, pic 5 for example

Pics attached, thoughts would be appreciated
 

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@Bellow

It's been a few weeks since I replaced the banjo bolt, o ring and sealing rings, thought I'd go and check underneath before putting the undertrays back on but lo and behold there is still a leak, I'm at a loss as to what it could be it's definitely engine oil
I honestly don't know - and I'm not familiar with your engine to hazard a guess.
Could it be the sump? or the seal between the transmission?
Shouldn't be because there shouldn't be oil within that void - only the (sealed) torque convertor.
If there is, it points to a leaking rear crankshaft seal - are these engine prone to that?
Are the engine breathers all clear? Choked breathers can allow crankcase pressurisation which can force leaks.
But what throws me is there is signs of oil leak above those areas, pic 5 for example
The air movement in the engine bay can deposit oil from anywhere to anywhere. I'd wipe it all down (to dryness) and after the next drive to the same again with kitchen towel and try and identify the source of the leak before the oil has a chance to cover everything.
If you are absolutely certain it is engine oil, you have already narrowed down the possibilities.
 
Are you sure it is a turbo line? Looks a little low for that. And - though it's hard to be sure from the photos - where the pipe is of larger outer diameter it appears to be rubber. Turbo lines are usually hard throughout.
 
Turbo line has been eliminated as the banjo bolt, seal and o ring has been replaced.

I also posted in mb world and have been advised it could also be the valve cover gasket as the cylinder head cover is part of the PCV circuit and is pressurized, so any weaknesses in the gasket will allow oil to be blown out

Although I'm not convinced as I can see no signs of an oil leak between the cover and engine!
 
I also posted in mb world and have been advised it could also be the valve cover gasket as the cylinder head cover is part of the PCV circuit and is pressurized, so any weaknesses in the gasket will allow oil to be blown out
It shouldn't be pressurised.
Petrol engines run a slight vacuum in the crankcase. To prevent pressurisation when the turbo is boosting there is (usually) a one-way valve in the line that leads to the inlet manifold. These if they stick (open) will permit the crankcase to become pressurised and promote leakage. That's how it is with port injected turbo petrols at least. Direct injection units are possibly different - but if they have a throttle butterfly, probably not.

The one-way valve is easily checked by removing and blowing through it. It should only flow in one direction.
 
It shouldn't be pressurised.
Petrol engines run a slight vacuum in the crankcase. To prevent pressurisation when the turbo is boosting there is (usually) a one-way valve in the line that leads to the inlet manifold. These if they stick (open) will permit the crankcase to become pressurised and promote leakage. That's how it is with port injected turbo petrols at least. Direct injection units are possibly different - but if they have a throttle butterfly, probably not.

The one-way valve is easily checked by removing and blowing through it. It should only flow in one direction.

Not sure what else to do :( either I wait for it to get worse which hopefully will allow me to identify the source of the leak or just change the valve cover gasket and see how I go.

May also take it to a garage to see if they can pinpoint the leak
 
@Bellow Could the air intake hose cause such a leak?

The connection doesn't appear to be in the best condition!

Also the turbo return line has signs of oil
 

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@Bellow Could the air intake hose cause such a leak?

The connection doesn't appear to be in the best condition!
Yes - if the pipe is downstream of the turbo ie, pressurised. There's usually some oil 'carry over' going on in the induction system but as I'm not familiar with diesels, hard for me to be more specific.
It might be worth tightening the clamp a little in case it's on the slack side. Do it after a run when everything is hot and the hose more pliant.
Also the turbo return line has signs of oil
It does look a bit dirty for a new seal.
 
Yes - if the pipe is downstream of the turbo ie, pressurised. There's usually some oil 'carry over' going on in the induction system but as I'm not familiar with diesels, hard for me to be more specific.

It does look a bit dirty for a new seal.

It's a petrol not a diesel, c250 cgi facelift blue efficiency saloon
 
It's a petrol not a diesel, c250 cgi facelift blue efficiency saloon
Apologies for my dreadful slur!
The only turbo I've had was a petrol smart and there was always a bit of oil in the induction system - carry over from the turbo compressor and/or the PCV system.
Try tightening the hose clip (when warm).
 
Apologies for my dreadful slur!
The only turbo I've had was a petrol smart and there was always a bit of oil in the induction system - carry over from the turbo compressor and/or the PCV system.
Try tightening the hose clip (when warm).
Haha 🤣

Will try tightening the jubilee clip
 

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