TDCi (apparent) head gasket failure

Mondaveo · 04-12-2021, 01:32 AM

So I dropped the car off Friday at a local independent mechanics' shop to carry out the 10-year major service (timing belt change, etc).

Around lunchtime they rang me up to say that after removing the old belt, they'd uncovered that the head gasket has failed and is allowing coolant to leak down the front of the engine. It wasn't wet (which would indicate a catastrophic leak) but there is clear evidence that seepage has been occurring behind the timing belt cover, originating from between the engine block and cylinder head.

I discussed the situation with the technician a bit who advised that it's not likely to worsen rapidly and I'll be able to have forewarning that it's getting bad by monitoring the coolant levels and watching for puddles under the car, etc. (I may be able to inspect for myself with the timing cover off also.) On that understanding that it may be okay for at least a little while I gave the go-ahead to proceed with installing the new parts and completing the service.

The tech advised that with a diesel, replacing the head gasket is not really viable as it's a very involved job, and that diesel engines are never really the same once it's put back together. ("Not a job we'd be happy to do.") He floated engine replacement (with a second-hand unit) as a safer option. Or promptly trading-in the car.

It bites, after the brouhaha with the transmission 5-6 years ago I was really hoping to get good service out of this vehicle for many years to come. It even felt markedly better driving back after the service (fresher, smoother, more responsive), but I can't escape this is probably terminal for the engine. The absolute best I can hope is the leak never worsens?

Pic below provided to me by the tech after removal of the old timing belt.

whitelion65 · 04-12-2021, 07:44 AM

Bugger! Doesn’t look too bad though.
I’d be rolling the dice on continuing to use it. What have you got to lose? It’s not likely to catastrophically fail suddenly. The only issue would be if it lets you down inconveniently.

Mondaveo · 05-12-2021, 10:12 PM

Well.
I've got a young family (three kids under 7) so safety and reliability are priorities for the family vehicle.
Unfortunately it looks like those were delete options on this example

We do have a fair business case for getting into a people mover (and I do like the new Carnival) but I was hoping to forestall making any kind of upgrade for at least another five years. Because finances, and I do (or I did) like my wagon.

I'll certainly continue to use it while I try to gauge how bad this leaking is over the short term. I still need to get a look under the timing cover for myself and set up a monitor on the coolant level. Maybe it won't significantly worsen, and I'll arrive at the belt change 20 year service and wiping the same little wick of seepage off the block. Or maybe she'll be kaput in six months, hard to say

What's to lose? While it's still a functional car, and the problem is minor, I could trade it in and at least get something toward replacement. If in the time it takes to understand the scope of the problem it worsens significantly then I possibly won't be able to unload it at all. But these retain so precious little of their value, I'm unsure whether that's in my favour or not...

Citroënbender · 05-12-2021, 11:05 PM

What about temporarily looping the heater hoses and getting a leak-chasing sealant into the motor? Even if you do that annually, it should see you good. Look for one that mentions the block, not just a radiator leak temporary fix.

I understand the mechanic’s reticence about a head off repair, the issue is these usually come after overheating and that’s when you have all the joys of stuff like precomp chambers loosening.

Tassie f100 · 06-12-2021, 09:13 AM

Maybe try backing off the head studs and retorquing as they seem to loosen over time.Years ago with the Jap import engines head gasket leaks were very common,but we found by retorquing head studs the problem was almost nonexistant.

**aussiblue** · 06-12-2021, 02:26 PM

Perhaps ask Allan Howatt of Steve's Taxis and Car Sales Alconbury UK https://www.youtube.com/c/alan4x6677 Try messaging him at https://www.facebook.com/alan.howatt/about He'll certainly an expert with these engines and will know if the advice you got is correct and the alternatives. He's apparently pretty responsive to such request but I locate his email address. Perhaps try him at StevesCarSales@stevescarsalesalconbury per https://www.facebook.com/stevescarsalesalconbury . Otherwise wait for one of his YouTube Question and Answers love streams.

cobrin · 06-12-2021, 05:55 PM

I'll have to look at my photos Mondaveo, I don't want to get your hopes up, but I'm not seeing an issue here personally.

Have you ever washed down the engine, or it has gotten wet by driving in the wet?

I'm sure mine took me by surprise with rust patterns, but I did have a weeping WP. Me personally I'd drive it and enjoy it till a problem arises. Monitor coolant for now, but it shouldn't be a cause of concern.

Again I'll have a look at my original pics.

NZ XR6 · 06-12-2021, 09:05 PM

Quote:

Originally Posted by cobrin

Have you ever washed down the engine, or it has gotten wet by driving in the wet?

I'm sure mine took me by surprise with rust patterns, but I did have a weeping WP. Me personally I'd drive it and enjoy it till a problem arises. Monitor coolant for now, but it shouldn't be a cause of concern.

Agreed, I'm not sure that a coolant leak would leave marks like that.

Did they do a pressure test or any tests on the coolant such as leak down?

Sent from my SM-G980F using Tapatalk

Mondaveo · 06-12-2021, 09:44 PM

Thanks folks for the suggestions.

Quote:

Originally Posted by Citroënbender

What about temporarily looping the heater hoses and getting a leak-chasing sealant into the motor?

When I received the news I asked their opinion on the magic gasket-in-a-bottle (my brother has had success using one of those products on his venerable Vauxhall). The response was that those solutions require the heat of the combustion chamber to trigger the chemical reaction that seals the leak, so unlikely to work for a leak on the exterior here. Though there could be different formulations that are ideal for this application, I'm not sure. Still, it would be worth trying before putting the engine out to pasture.

Disconnecting the heater core is an ingenious idea so thanks for that.

Quote:

Originally Posted by Citroënbender

I understand the mechanic’s reticence about a head off repair, the issue is these usually come after overheating and that’s when you have all the joys of stuff like precomp chambers loosening.

That's a good point. If it were to come to it I would shop around to see if there are other shops that might view performing the repair more favourably. (Although from reading my Haynes manual it sure doesn't seem like a great job.)

Quote:

Originally Posted by Tassie f100

Maybe try backing off the head studs and retorquing as they seem to loosen over time.Years ago with the Jap import engines head gasket leaks were very common,but we found by retorquing head studs the problem was almost nonexistant.

My father-in-law had enough stories of machinery that wasn't bolted together right at the factory, so I asked the mechanic if anyone had checked the torque on the head bolts. The answer was no, but the reason is that it's a very involved job to even access them. If I'm reading Haynes right, these motors have a two-piece cylinder head, and one would need to remove the cylinder head cover integrated with the intake manifold (so, an opportunity to do Cobrin's manifold cleaning) AND the upper cylinder head and all its assemblies to reach the head bolts in the lower cylinder head.

Quote:

Originally Posted by aussiblue

Perhaps ask Allan Howatt of Steve's Taxis and Car Sales Alconbury UK https://www.youtube.com/c/alan4x6677 Try messaging him at https://www.facebook.com/alan.howatt/about

Yeah ok, I can try reaching out to him.

Quote:

Originally Posted by cobrin

Monitor coolant for now, but it shouldn't be a cause of concern.

Quote:

Originally Posted by NZ XR6

Agreed, I'm not sure that a coolant leak would leave marks like that.

Did they do a pressure test or any tests on the coolant such as leak down?

Sure, I hope you guys are right. The coolant level is currently a bit below the MAX mark so I'm topping it up to a clear reference mark and then we'll monitor. The shop cleaned up the engine for me so when I get to look under the timing cover I'll know any marks I see are new.

I don't think there were any tests done, the diagnosis was based on experience of seeing multiple motors with gasket failure (though they've never seen it on a diesel Mondeo before). The mechanic gave a first-hand account of a Falcon he owned, which had this issue and looked exactly like this when he bought it. He monitored it and over some span of time the leaking worsened, until he did the head gasket to repair it.

**Silver Ghia** · 06-12-2021, 10:39 PM

Quote:

Originally Posted by Mondaveo

Thanks folks for the suggestions.

When I received the news I asked their opinion on the magic gasket-in-a-bottle (my brother has had success using one of those products on his venerable Vauxhall). The response was that those solutions require the heat of the combustion chamber to trigger the chemical reaction that seals the leak, so unlikely to work for a leak on the exterior here. Though there could be different formulations that are ideal for this application, I'm not sure. Still, it would be worth trying before putting the engine out to pasture.

Disconnecting the heater core is an ingenious idea so thanks for that.

That's a good point. If it were to come to it I would shop around to see if there are other shops that might view performing the repair more favourably. (Although from reading my Haynes manual it sure doesn't seem like a great job.)

My father-in-law had enough stories of machinery that wasn't bolted together right at the factory, so I asked the mechanic if anyone had checked the torque on the head bolts. The answer was no, but the reason is that it's a very involved job to even access them. If I'm reading Haynes right, these motors have a two-piece cylinder head, and one would need to remove the cylinder head cover integrated with the intake manifold (so, an opportunity to do Cobrin's manifold cleaning) AND the upper cylinder head and all its assemblies to reach the head bolts in the lower cylinder head.

Yeah ok, I can try reaching out to him.

Sure, I hope you guys are right. The coolant level is currently a bit below the MAX mark so I'm topping it up to a clear reference mark and then we'll monitor. The shop cleaned up the engine for me so when I get to look under the timing cover I'll know any marks I see are new.

I don't think there were any tests done, the diagnosis was based on experience of seeing multiple motors with gasket failure (though they've never seen it on a diesel Mondeo before). The mechanic gave a first-hand account of a Falcon he owned, which had this issue and looked exactly like this when he bought it. He monitored it and over some span of time the leaking worsened, until he did the head gasket to repair it.

I'd first monitor the coolant level, leaving things such as heater hoses alone to start with. Expect the level to still drop slightly initially, after topping up as you mention. Conditions must be the same at each check in the morning after being left overnight with the car on a level surface in the garage at similar ambient temps each time, or allowing for ambient temp variations. Also expect coolant levels to still vary slightly each time, only when the level is consistently dropping over a relatively short period only then you should start thinking further.

And don't take too much notice of other peoples experiences, situations are generally different especially with different engine types.

AlanD · 07-12-2021, 04:52 PM

Hi Mondaveo,

I'm siding with Silver Ghia, Cobrin and NZ XR6 because I'm not convinced that what is shown in the photo is a gasket failure.

I'm basing this on what I suspect are fluid tracks on the face of the Head immediately above the gasket to the left of the welch plug. I think the head is an alloy (?) and that would not give the kind of corrosion marks you see on the face of the block.

I'm also thinking that the filaments of the head gasket that are shown protruding would tend to break up a slow fluid flow into a differing pattern on the block face when the fluid finds a path between the gasket filaments.

Keeping an eye on coolant levels is wise advice. I'd expect that you will not see major coolant loss in short periods of use. If that were to occur then it's time to get the timing belt cover off and have another look.

I would not be considering a change of vehicle or a major repair until things got considerably worse than they are now.

I'm betting that the rate of loss, if that is what it is, is so tiny that when the engine is running the fluid evaporates and does no damage. Once the engine is cool enough any fluid remains liquid and causes the tracks until the cooling system pressure equalises with the outside atmosphere, at which point any leak would stop.

Good Luck - if you need it

Cheers

Mondaveo · 07-12-2021, 09:41 PM

Alright alright you guys, you've convinced me (lol).

Agreed I should wait a little bit and see whether there's any evidence to back up the prediction of an untimely demise. The diagnosis did come from a professional but I suppose they might have it wrong.

I did think it odd that a diesel motor could have a fundamental weakness like this, since they need to be built strong to work at all. Also since the coolant is a ten-year service item, and I've never noticed it was getting low or had to top it up since I've owned the vehicle, it's either only leaked a minute amount or is not actually leaking at all.

The advice I've gotten from some who claim to know is I ought to just get rid of the black sheep. It's lucky we don't rely on experts or everyone might believe that Powershifts are going to grenade on you and Fords retain no resale value

XR Martin · 07-12-2021, 09:58 PM

I dont think there was ever an issue with the wet clutch powershift in the diesels, it was the dry clutch ones that was the problem.

Mondaveo · 08-12-2021, 12:29 AM

Not wanting to get off track...

Quote:

Originally Posted by XR Martin

I dont think there was ever an issue with the wet clutch powershift in the diesels, it was the dry clutch ones that was the problem.

Actually, early examples of the wet-clutch Powershift (up to sometime in 2012) were prone to a faulty electronic sensor that could cause erratic driving behaviour as it went bad. Replacement of the sensor cures the issue, but requires specialist skills and equipment as the transmission must be completely dismantled to reach it.

Ask me how I know!

bundybear75 · 08-12-2021, 10:19 PM

Quote:

Originally Posted by Mondaveo

Not wanting to get off track...

Actually, early examples of the wet-clutch Powershift (up to sometime in 2012) were prone to a faulty electronic sensor that could cause erratic driving behaviour as it went bad. Replacement of the sensor cures the issue, but requires specialist skills and equipment as the transmission must be completely dismantled to reach it.

Ask me how I know!

Me too.....

bundybear75 · 08-12-2021, 10:22 PM

I would not be surprised if the tracks you see, are remnants of engine cleaner or degreaser that may have squeezed past the timing belt cover in the past.

Detailers and car yards will go to town trying to make an engine bay look like new when selling a second hand car.

Fingers crossed its nothing serious

rondeo · 12-12-2021, 11:57 AM

To me it looks like it came from the water pump and ran up (drafts) to the head where it seems to stop short.

The draft might be from the timing belt. I think it is going up in that area?

**aussiblue** · 12-12-2021, 05:13 PM

Quote:

To me it looks like it came from the water pump and ran up (drafts) to the head where it seems to stop short.

Nah; as the rust stain is not past the water pump gasket area.

**aussiblue** · 12-12-2021, 05:20 PM

It is an odd one. If the head gasket was failing you would expect considerable more corrosion and rust stains. It's almost if it was assembled with some water or other corrosive fluid left on the face of the block.

rondeo · 12-12-2021, 06:06 PM

Looks to me like both trails lead to the pump mounting bolt holes, go around and then into the impeller cavity.

The left one turns left and the right one turns right.

Whatever the case, it doesn't look like a head gasket leak to me.

**aussiblue** · 12-12-2021, 06:07 PM

Has the owner OP actually looked at the engine yourself or is he relying on an emailed photograph? I would at least asked to view it yourself to may sure you are not being conned.

Can someone on this forum confirm that is actually a picture of MKIV Mondeo 2.0 engine as I cannot find a YouTube video for a timing chain/water pump change with a matching picture and it's not an engine I'm that familiar with? I been looking at all the videos and pics I could find of timing chain and water pump replacements to see if the had the same rust staining patterns.

**aussiblue** · 12-12-2021, 06:12 PM

Quote:

Looks to me like both trails lead to the pump mounting bolt holes, go around and then into the impeller cavity.

So perhaps the pump bolts go into the water jacket and required sealant (e.g. https://www.amazon.com.au/LOCTITE-11.../dp/B004QXL4F2 ) was not put on the bolt threads. But even then; water flowing upwards against the force of gravity?

**aussiblue** · 12-12-2021, 07:02 PM

Quote:

Looks to me like both trails lead to the pump mounting bolt holes, go around and then into the impeller cavity.

..and however much I blow up the photo I can't see that. It never appears to go past the outline of the outside of the gasket.

Tassie f100 · 12-12-2021, 07:23 PM

Quote:

Originally Posted by aussiblue

..and however much I blow up the photo I can't see that. It never appears to go past the outline of the outside of the gasket.

Certainly with you on that Blue,there’s no sign of water stains inside the pump gasket line. Wouldn’t surprise me at all if it isn’t old washdown water stain.I would be just keeping an eye of any water usage for a while

bundybear75 · 12-12-2021, 10:13 PM

https://youtu.be/OWkTJToMW1M?t=399

Almost identical water marks on this engine

rondeo · 13-12-2021, 08:26 AM

It's been three years since I did my timing belt, but yes the photo does match the engine.

On mine the water pump seal was weeping, so another theory might be that coolant came from there...

The belt runs more or less between the two tracks of supposed coolant in the photo. The idler mounting bolt holt can be seen immediately to the right of the tracks. My thought was that given it's a ribbed belt whoosing up through there maybe the coolant was swept up.

Mondaveo · 21-12-2021, 10:51 PM

Been looking to get a second professional opinion, and I've come across a mobile mechanic who operates locally with a specialisation in French cars (a former Citroen/Peugeot master mechanic who quit the dealership and went independent).

Mondeo, we know, runs the joint Ford-Peugeot-Citroen diesel engine and thus falls within his purview.

I've asked his thoughts on the photograph I got from the other mechanic and this is his take:

Quote:

That stain I'm rusty brown is not head gasket. It's from water when engines washed. It sits around the injectors and slowly seeps down. I wash every engine after service and degrease and all appear like that behind cam belt cover.

So weight of opinion is coming down handily on the side of this being a washdown stain and nothing to worry for.

bundybear75 · 22-12-2021, 06:32 AM

Quote:

Originally Posted by Mondaveo

Been looking to get a second professional opinion, and I've come across a mobile mechanic who operates locally with a specialisation in French cars (a former Citroen/Peugeot master mechanic who quit the dealership and went independent).

Mondeo, we know, runs the joint Ford-Peugeot-Citroen diesel engine and thus falls within his purview.

I've asked his thoughts on the photograph I got from the other mechanic and this is his take:

So weight of opinion is coming down handily on the side of this being a washdown stain and nothing to worry for.

You wouldn't be able to DM me his details - I need to get the glow plugs replaced in my Pug - looks like a s&*t of a job. Not sure I want to tackle it myself