Mondeo Mk3 2.5 V6 oil leak from the sump
Discussion
Hi guys,
I have a 2002 Mondy Mk3 2.5 V6 petrol auto with a leak from the sump. I have been told that this is not simply a sump gasket failure, but the result of a broken piston ring pressurising the sump, thus causing the leak. I am surprised that the garage did a compression test and found probable ring damage in number five cylinder - I am even more surprised that the car has just been MoT'd with perfect emissions, does not burn oil, nor is there any loss of power, or any other symptoms of engine problems. I am even more surprised that when I asked the mechanic to service my other Mondy V6 he asked me to find out how to remove the spark plugs as it looks a complicated job! He must have alzheimer's!
I feel like I am being set up! I have not heard of this symptom of ring damage before and wonder if you guys had any advice or comments to make.
I have a 2002 Mondy Mk3 2.5 V6 petrol auto with a leak from the sump. I have been told that this is not simply a sump gasket failure, but the result of a broken piston ring pressurising the sump, thus causing the leak. I am surprised that the garage did a compression test and found probable ring damage in number five cylinder - I am even more surprised that the car has just been MoT'd with perfect emissions, does not burn oil, nor is there any loss of power, or any other symptoms of engine problems. I am even more surprised that when I asked the mechanic to service my other Mondy V6 he asked me to find out how to remove the spark plugs as it looks a complicated job! He must have alzheimer's!
I feel like I am being set up! I have not heard of this symptom of ring damage before and wonder if you guys had any advice or comments to make.
Guys, thanks very much for your feedback which is greatly appreciated. I too feel that blocked breathers (not uncommon) is the issue here. A broken piston ring is extremely unlikely as this would result in (i) MoT failure on emissions - the car has just passed its MoT last week with perfect emissions (ii) Rough running - the car runs sweet as a nut (iii) Loss of power - there's no loss of power (iv) Burning oil - the car does not burn oil.
Basically someone is trying to rip me off; they said they had completed a compression test on the car, then when I asked them to service my other Mondeo, which is again a 2.5 V6 (exactly the same engine) they asked me to find out how to remove the spark plugs "...as it looks complicated"!! Mm....then how did you do the compression test on my other V6 Mondy??
There are also other jobs they have said they have done which they clearly haven't. What makes this worse?....this person has been a "friend" for almost twenty years.
Basically someone is trying to rip me off; they said they had completed a compression test on the car, then when I asked them to service my other Mondeo, which is again a 2.5 V6 (exactly the same engine) they asked me to find out how to remove the spark plugs "...as it looks complicated"!! Mm....then how did you do the compression test on my other V6 Mondy??
There are also other jobs they have said they have done which they clearly haven't. What makes this worse?....this person has been a "friend" for almost twenty years.
Absolute nonsense. Even if someone had done a compression test it's not possible to diagnose a broken ring from that. At best one might differentiate between bore wear and a blown head gasket/ valve problem by doing a test with and without some oil squirted in (dry vs wet test) but to go as far as a saying there's a broken ring is gibberish at that stage.
Plus as you've been told the whole engine is vented by the breathers and pressure can't build up in it anyway unless they're blocked which would cause enough problems of its own.
It's 15 years old. Things do start to leak at some stage. No reason to suspect it's anything other than a new gasket which is needed.
Plus as you've been told the whole engine is vented by the breathers and pressure can't build up in it anyway unless they're blocked which would cause enough problems of its own.
It's 15 years old. Things do start to leak at some stage. No reason to suspect it's anything other than a new gasket which is needed.
Just to add - access to the rear bank of spark plugs is an absolute swine! On the Mk.2 at any rate I have heard of people removing the bonnet to get better access. Which reminds me, my dad is having a clutch change on his (100k miles) so a spark plug change might not be a bad idea while the engine is out.
He's been quoted £500-600 inc parts which seems very reasonable. Okay, the car probably isn't worth that, but to replace it you are talking at £5-6k and that would be a car that was 70-80k miles anyway. Good 2.5Ts are like hen's teeth, and 2.2tdci TXSs are just not doing it for him after being used to a sweet revving V6 all these years, and I have to say I agree.
He's been quoted £500-600 inc parts which seems very reasonable. Okay, the car probably isn't worth that, but to replace it you are talking at £5-6k and that would be a car that was 70-80k miles anyway. Good 2.5Ts are like hen's teeth, and 2.2tdci TXSs are just not doing it for him after being used to a sweet revving V6 all these years, and I have to say I agree.
Zad said:
Just to add - access to the rear bank of spark plugs is an absolute swine! On the Mk.2 at any rate I have heard of people removing the bonnet to get better access. Which reminds me, my dad is having a clutch change on his (100k miles) so a spark plug change might not be a bad idea while the engine is out.
He's been quoted £500-600 inc parts which seems very reasonable. Okay, the car probably isn't worth that, but to replace it you are talking at £5-6k and that would be a car that was 70-80k miles anyway. Good 2.5Ts are like hen's teeth, and 2.2tdci TXSs are just not doing it for him after being used to a sweet revving V6 all these years, and I have to say I agree.
I have heard about the spark plugs! Both of my cars are due for a change. I love my Mondeo's. I have had a rear subframe replaced with a new one on one of them costing around £500 including trailing arms, drop links, anti-roll bar bushes etc which was worth it as the car is in excellent condition. The other car, thankfully, appears to be fine!He's been quoted £500-600 inc parts which seems very reasonable. Okay, the car probably isn't worth that, but to replace it you are talking at £5-6k and that would be a car that was 70-80k miles anyway. Good 2.5Ts are like hen's teeth, and 2.2tdci TXSs are just not doing it for him after being used to a sweet revving V6 all these years, and I have to say I agree.
A friend of mine bought a new Mondeo TDCi in 2003 and loved it I remember. When I was looking for a Mondeo my local garage warned me off the TDCi saying that they were very problematical, so I went for the V6 2.5 which is a superb engine in my opinion. Fuel economy is not bad, but I only do around 100 miles per week anyway.
By the way, I love the Mk2 Mondeo, and may sell my Volvo V70 S1 2.5 to get an estate version as my everyday work car.
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E-bmw said:
Possible, but I would have thought unlikely that there would be sufficient to blow oil out of the sump, possible though.
Main breather route was blocked in my RRC V8 when I bought it - the channels in the plenum were solid with crud & needed a drill bit used by hand to clear it - and I can assure you it can cause oil to leak out of all sorts of interesting places
brrapp said:
Is it a steel or alloy sump? Mondeos can have either depending on age or engine model. The steel ones actually rust through from the inside (amazing for a metal container filled with oil) and become porus and the oil just sort of seeps out with no visible leak source.
This is generally because the powder coating on the sump pan gets stone chipped and water gets in between the coating and the bare metal and then the corrosion happens out of sight until the inevitable leak!Gassing Station | Engines & Drivetrain | Top of Page | What's New | My Stuff