Hyndai I10 engine using coolant – bad diagnosis?

Need some help checking a garage isn’t trying to rip my mum off.

She has a 59 plate I10 that has been using coolant slowly over the last few weeks. We were monitoring it and it was using roughly 100ml every 100 miles or so. I couldn’t spot any obvious leaks and there were no telltale drips underneath it after a longish run or if it was left standing either. It had it’s MOT two weeks ago and passed with just an advisory on the tyre wear and one on a rusty brake pipe.
Last week though it started to use more coolant and yesterday it used a litre in 26 miles so it was taken to the local garage a mile away from her. They drew a blank on any leaks so he got a friend to give a second opinion and now they want to replace the engine! The report has come back saying that it’s pouring coolant through the exhaust and only running on two cylinders but mum and dad have both said it was running fine, plenty of power with no smoke, steam or leaks it was just using coolant. Dad used to race vintage cars and has rebuilt whole cars before so knows his way around a car and my mum isn’t stupid car-wise either and they both think it sounds fishy. I moved the car around 3 days ago and it started and ran fine, I’m suspecting the head gasket has gone drawing coolant into a cylinder.
They’ve used this garage for a long time but recently locals have been mumbling about his prices going up and suspected unnecessary work being done too, we’ve had no issues until now but this smells a bit fishy. Surely if the engine has gone it would run rough or give some sign it was unhappy but as long as you keep the coolant topped up it runs fine. It’s done 68k so shouldn’t be worn out yet!

Does it sound like the engine’s gone or a head gasket as I/we suspect? Dad’s going to ask the garage to whip the head off and look inside as he trusts the owner but not his mate. As some of you may know my parents are caring for my cousin right now so having a car is important to them right now.

Could be a thermostat housing seal. You don’t always see evidence of a leak because the coolant evaporates as it comes out.

…and what is the mechanism to get coolant water into the exhaust? I am a long way from an expert on engines, but don’t see how the coolant circuit would get anywhere near the exhaust.

And surely you’d notice a 4cyl engine running on only 2 cylinders….?

I’ve got an 11 plate i10 and was losing coolant quite dramatically and that wasa cracked thermostat housing. They are a bugger to get off though. Again, I would question how it was getting into the exhaust, other than through the cylinder head. Running on two cylinders as well? Youd feel and hear that.

That’s what got me suspicious, the coolant would have to go through the cylinder and get pushed through the exhaust port. If it was leaking like they say it is it would hydrolock the engine. A dodgy thermostat was my original thought when it started losing coolant as the engine was struggling to get up to temperature unless it was driven hard.

Dad’s just rung me back and the garage are unwilling to remove the head to look inside, they’re just saying it needs a new engine so I’m going there tomorrow and we’ll get the car back. If I can’t spot anything obvious we’ll take it somewhere else and get a second opinion.

Any sign of oil contaminating the coolant? I thought mayo was the big giveaway for a blown head gasket.

And surely you’d notice a 4cyl engine running on only 2 cylinders….?

I think they’re 3 cylinder engines, but all the same…

It is possible for the water to get into the exhaust directly, if there is a crack, or porosity where the water jacket and port are in close proximity. The wall section between the two will typically be around 5mm

(I cast cylinder heads for 27 years at Nissan)

Im pretty sure that some cars can have a coolant leak at the water pump. I think its a Seat/VW know problem, as they aleays replae the water pump at cambelt change time.
May be worth checking there?

If they won’t remove the head there’s no way they can call it a write off. It could be anything from simple thermostat failure to a cracked head, or anything in between (although if it’s genuinely losing that much then my guess would be head gasket failure between water gallery and cylinder bore)
If it is head gasket then unless something catastrophic had happened, chances are a new HG and a head skim will fix it. Unless it’s some bonkers set up then that shouldn’t be too pricey at a decent Indy.

TL:DR – take it somewhere else.

I’m suspecting the head gasket has gone

… was my first thought.

TL:DR – take it somewhere else.

… was my second.

I thought head gasket. Unless it’s particularly hard for them to remove it and they reckon it’s just easier to put a new engine in! The oil only turns to mayo if the damage is between the coolant and oil systems.

It’s quite possible to lose that amount of water through the engine (via head gasket) without hydraulically locking the engine. How many revolutions do you reckon it does in that time? How much fuel has been through the engine?

It’ll be coming out as steam anyway.

Of course, if they’ve not checked anything to do with the head gasket, I’m not sure how they could know it wasn’t that (Maybe they’ve looked for mayo but found none, I’ve encountered bike mechanics with similar weird attitudes to the causes of problems). So it’s hard to tell if they’re talking shit about the water coming out through the engine/exhaust. And it would lose compression to some degree too, which you’d probably notice (although I’ve had a similarly buggered head gasket without it being particularly noticeable when driving except for water consumption) Second opinion/check the thermostat housing etc.

As for the ‘mayo in oil’ thing – as a general rule a head gasket keeps three things apart: coolant, oil, and combustion bits. It could fail in a number of ways, all of which will exhibit different symptoms:
– if it goes between cylinder and coolant passage, you can lose coolant, get steam out of the exhaust, combustion gasses in the coolant, or excess coolant pressure
– if it goes between oil gallery and cylinder you can burn oil, get fuel dilution in the oil or get excessive crankcase pressure, often seen by the dipstick getting blown out
– if it goes between oil gallery and coolant gallery you can get oil and coolant mixing, so you may get gunk in the coolant header tank or mayo (emulsified oil) in the oil filler cap.

(The above is just a few examples, and not exhaustive!)

What I’m trying to say is that ‘mayo’ is neither the definitive test for HG failure (some cars get it when they’ve just been parked up in the cold for a while) or the only sign. 🙂

OP’ easy, non invasive thing to do is commonly called a ‘dip test’ – any garage worth it’s salt should be able to do this, it’s basically a test for combustion gas in the coolant, which is a pretty solid clue that the HG has gone.

If it was leaking like they say it is it would hydrolock the engine.

Doubtful.
We had a golf that was losing coolant slowly then it got quicker…. It was the water pump.
To check to see if it’s getting into the cylinders pull the plugs…. They should be chocolate brown but if one looks clean then it’s a good indication that there’s coolant getting in.

We had a Fiat Punto with a failed head gasket like that. The water temperature was quite erratic too, but it didn’t run rough or terribly steamy.

A bottle of really good sealant sorted it, because nothing lost by trying. Saved a few hundred quid until trade in time.

… which is a point in itself.

Ten year old i10? Flog it / trade it and it’s someone else’s problem.

Any sign of oil contaminating the coolant? I thought mayo was the big giveaway for a blown head gasket.

There wasn’t last time I checked but they don’t always do it. I had a Citroen AX when I was a penniless student and ran it for 3 weeks just topping it up with water every journey as the head gasket was shot, no mayo or steam anywhere! On the plus side it had lovely clean valves on cylinder 3 when I did change it next payday.

I’ll be asking straight away what diagnostics they have done, if any. I know about the ‘dip’ test and checking the plugs, coolant reservoir and any smell/steam out of the exhaust, if they haven’t done the basics we’ll be taking it elsewhere.

Ten year old i10? Flog it / trade it and it’s someone else’s problem.

Mum’s thinking that way as she’s already looking at newer stuff we can look at tomorrow. She’s bipolar so if she doesn’t have trust in something it gets changed. The garage have put the fear in her now that it’s unreliable so even if it does get fixed it’ll be most likely getting changed soon. I hope I’m just being paranoid and it is genuinely an engine failure but as others have said above it doesn’t seem right. A spares/repair i10 with 12 months ticket’s got to be worth something?

Dad getting cancer, cousin taken into care, knackered car. That’s 3 right? Where’s the good luck?

Sounds like you’re getting shot of it.

In the past I’ve tested for coolant leaks by connecting a cheap tyre compressor to the overflow pipe of the expansion tank and removed the cap.
I then blocked the filler with the palm of my hand and pumped up to about 10 psi. Any leaks soon become apparent.

It wants a pressure test doing on it for starters

Pull the plugs out are they all the same colour.

Expansion bottle cap. Is it vented is the seal in good condition.

Does it have a water cooled egr?

Any of the owner forums report cracked heads as an issue.

I’d not go full engine swap. And if its that bang it in as a PX against another if your mum likes it.

Andy do I blame you for the shit yd25 heads then?

if she doesn’t have trust in something it gets changed. The garage have put the fear in her now that it’s unreliable so even if it does get fixed it’ll be most likely getting changed soon.

I was thinking more that a) it’s at about the right sort of age to start having expensive problems every other month and b) this is exactly the sort of issue that might require multiple “fixes” to actually fix conclusively.

And of course c) what’s a 10yo i40 worth, a grand? £1500 maybe? I’d hazard that something as ‘simple’ as a head gasket replacement is somewhere between half the value of the car and a write-off. New engine? Yeah, no.

You can get a test kit that fixes on the header tank that changes colour if it picks up any combustion gases in the water. That will at least tell you if the head gasket has gone.

Test Kit

Lets assume the garage has done the correct diag on this. An old Korean car will not be worth repairing, so just go for the K-Seal fix:

Well we’ve got the car back as the garage didn’t want to work on it. He was very dismissive of telling us what diagnostics he did so I drove it the mile back home. Starts on the button and the engine runs perfectly fine so it’s sat outside my parents house while we discuss what to do.

Current thinking is to go looking at other cars and if she likes something we’ll get it then worry about offloading the Hyundai in the next few weeks. She wants reliability, which she now doesn’t trust the Hyundai to give her, so even if it was fixed she’d be wanting to get rid soon anyway. That gives me a bit of time to poke around it and see what it could be, if it’s a cheap fix I’ll do it then sell it otherwise it’ll be sold as spares or repairs.

Really annoyed at the garage being very dismissive of repairing or properly investigating it, really unlike them. Could have something to do with they just MOT and serviced it and are worried they’ll find something we can pin on them. Either way it’s a whole lot of stress we could really do without right now.

inbred456 – I’ve ordered that kit, handy to have! I’ve had the car running for a bit outside and it’s not using any coolant currently, no leaks evident either. No time to do anything else today so I’ll put it in the garage and look at it another day.

My wife’s last started guzzling coolant; dealer said it was likely ‘a warped cylinder head’

Turned out to be the heater matrix; still £1500 to fix so bottle of goo as above then PX for something shiny

Current thinking is to go looking at other cars and if she likes something we’ll get it then worry about offloading the Hyundai in the next few weeks. She wants reliability, which she now doesn’t trust the Hyundai to give her, so even if it was fixed she’d be wanting to get rid soon anyway. That gives me a bit of time to poke around it and see what it could be, if it’s a cheap fix I’ll do it then sell it otherwise it’ll be sold as spares or repairs.

Isn’t this exactly what “part exchange” is for?

I’ve ordered that kit

Back in my day we used to just drop an egg into the water.

This had hilarious consequences one time when my then-girlfriend was on her way over to my house, the fan belt snapped and she thought “ooh, I wonder what all those pretty coloured lights mean?” and kept going. As I discovered following a panicky phone call not long afterwards, it’s surprisingly difficult to chisel cooked scrambled egg off a Mini windscreen.

Yes heater matrix is another possibility – do the windows steam up badly?

Lets assume the garage has done the correct diag on this. An old Korean car will not be worth repairing, so just go for the K-Seal fix

K-Seal – that’s the brand I used 👍 Bloody effective!

Just to update and give this an ending: another garage has looked at the Hyundai and says it’s a head gasket that’s gone. They just did the basic tests: plugs out, pressure testing the coolant system and a camera in the cylinders and a compression test. It’s sucking water in on cylinder 3 but it pressurises fine, hence why it runs smoothly. Cost to repair is over £500 due to it needing a skim and the parts cost (belt/chain and tensioners, can’t remember which it uses), that’s more than it’s worth on a very good day so it’s now sat in my parent’s garage waiting for me to give it a good clean prior to selling it as spares or repairs. The head is perfectly fine otherwise, no porosity.

Mum had pretty much made up her mind it was new car time before we knew this so she now has a 5 year old Nissan Note we spotted for sale on the way back from taking my dad to hospital, much easier for them both to get in and out of so they’re happy. She even made a passing comment when the salesman asked how she was paying for it by replying dead-pan “His inheritence!” I couldn’t give a toss, their safety, mobility and happiness are far more important.

Isn’t this exactly what “part exchange” is for?

Usually, yes. But this car doesn’t go very far without losing coolant and it’s also covered in little scratches with an interior that stinks of smoke and is ingrained with ash. Oh and it has lots of dog hair in it too! We did ask at the garage we got the Note from and they gave us a better price without it so it’s going to get listed locally as a spares car or sold to a local breakers, whichever gets us a decent price. It’s the common sliver colour and all the panels are sound (bar light scratches) so it’s got value as a donor, plus the mechanicals that do work. That’s a job for me next week.

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