Cars of Crackers - Boat.

[SiC]

I'd pressure test and vacuum bleed it too. See if there are any leaks and also prevent any air locks in the system. Are these prone to air locks?

[Bren]

I am sorry you are having more problems.

My 530d is a 62 plate. I have found myself looking at newer - but dull - cars as I am getting the fear that it may throw up a huge bill.

[Six-cylinder]

On 03/02/2026 at 13:04, JMotor said:

TL:DR - Coolant caps can be shit.

Had a similar problem with 1.8 K powered ZT. I replaced the seals in it, but the car was sold before I knew if it had worked.

Might not be the actual fault. But it's cheap and easy to do.

My Rover 114SLi lost a load of water on the way Gaydon Museum, that turned out to be simply a split header tank cap. It was a worry that I had suffered HGF!

[warninglight]

Another vote here for a pressure test. Get some of the UV coolant dye, chuck a bit of that in and pump it up so 13psi or so.

If it's finding a way to leak when hot you'll find it in no time with a UV light.

If it holds pressure for ages without leaking then change the cap!

[Crackers]

Got an empty spot in your yard? Wanna make some money?

Buy my scrap!

"Just scrap it" comments need not apply thanks. 

[Crackers]

^I stupid put this on Facebook for the same money earlier and have already been so inundated with silly questions such as "is the just the fuel rail" and "does it start". 

I can't deal with these fuckwits, I've deleted the FB ad and will repost it with another £400 on the price to see if I can catch anyone with more than one brain cell...

On the plus side, if there's already been that much interest, I shouldn't have too much trouble selling it. 

£1000 price on here still stands if anyone wants a really nice car for almost free. 

[Talbot]

I am significantly* annoyed about the situation with your Jaaag, as to my detriment, I recommended the garage at which it has been sat for the past year.  He is a decent garage, but his communication is non-existant, and clearly he's just not been getting on with this one at all.

I need to pay him a visit very shortly myself, so I'll see if I can fathom what the actual fuck he's playing at.

[Crackers]

7 hours ago, Talbot said:

to my detriment

Not at all, don't worry about it. You were never to have known it'd go this way, so absolutely no reflection on you! 

To be honest, I'm in line with the comments from people on previous pages - it's probably not worth repairing now unless it was done for the cost of parts only, which would be a little unfair.

I need to confirm with him that the car is still there and in a position where it could be collected on a truck, so it can become someone else's problem via Facebook. I'm passing this weekend for the first time in ages, so I might pop in... 

[vaughant]

Sorry to hear about your car woes 😭😭😭, I was quite fancying that mg myself.

If you want something reliable I can recommend a Merc w205 2.1d, or really any of the 4 cylinder diesels. I've no idea jl on the 6's but I've not heard of any real horrors.

I always say it but we've had little bother with ours and 4 others I see regularly have them and have had no majors. Just keep up with the servicing. They're really nice to drive as well. 

Banger to get you about I'd also highly recommended the Laguna 3. Chain engine, solid, very well put together and hugely un-French electrics 🤣🤣🤣. Mines just clicked over 201k, still runs perfect getting hammered up the motorway everyday right now and even if left for weeks of only occasional use, it still works fine. 

Mines a non dpf model which the FAP apparently can give troubles so worth remembering.

I think the Mégane 3 is a good car as well, but it needs a belt being a 1.5d, still easy to factor into the price.

Honestly a few years ago I laughed at French cars thinking how shit they were in every respect but I'm happy to admit I was hugely wrong. They've been my main form of conveyance since 2020 where I've worked away in all that time and I've never failed to get to work. I think they're well set up to take the abuse the french give them as they care very little about cars as they don't seem to carry the status out there that they do in Britain, like the minimum wage worker still living in a terrace with her nan up the Rhondda driving a Merc on finance parked in the street with a plate like P41AGE or T33GUN on it.

In France millionaires still seem to drive 15yr old Clio's and Berlingo's.

[Crackers]

HGF? 

Dunno m8. Fluid Was meant to turn yellow if it's got combustion gas in it.

The instructions sheet says "Green = Inconclusive", so that's brilliant. 

Lost several litres of water running it with the cap off (don't how normal that is?) but according to the digital readout on the dash, it never got hotter than 93deg.

Didn't notice the cooling fans come on although I wasn't really paying attention as I was on the phone. Definitely didn't overheat. 

Might try a new coolant cap before any more drastic measures.

Notice how clean it looks? My mate waxed it for me and it looks amazing now. To counteract that, the headliner fell down. 

Fucking cars. 

[Heidel_Kakao]

At least the headliner is easier to replace with it being an estate.

[RoverFolkUs]

@Crackers whereabouts in Sussex are you? From your Jag advert it sounds like we may not be far from eachother at all

I'm in-between jobs at the moment and have the next couple of weeks off. With your utter shit luck with cars, if you get really stuck I'd be more than happy to help another shiter out and take a look at the MG with you to see what it might need and whether I can decipher any signs of OMGHGF? 

Sometimes another pair of eyes with a fresh mindset is all it takes 

[SiC]

21 hours ago, Crackers said:

The instructions sheet says "Green = Inconclusive", so that's brilliant. 

I kept getting this on the Astra H that I fixed this weekend. That had boiled over at least 6 times (she admitted that it was actually far more than that). After I fixed the fault (thermostat jammed shut) and replaced the cap which broke, it's done ~35 miles fault free. She's now going down to Cornwall in it, so we'll see if it's still consuming coolant.

How long are you doing the test for? My instructions say an absolute maximum of 5 minutes as the heat from the coolant will affect the test result colour. I did the test three times (actually four but one I had it too hot and it boiled all it's coolant out) and got the same result.

New fluid for colour comparison under the light I was taking photos in.

Results

This last one I kept religiously to the instructions and stop the test in just under 4mins. To me this is still the most blue.

Looks to be a similar result you are getting?

Maybe not all lost and at least not yellow.

21 hours ago, Crackers said:

Lost several litres of water running it with the cap off (don't how normal that is?) but according to the digital readout on the dash, it never got hotter than 93deg.

You'll get evaporation when the coolant is that hot with no cap on. Sounds a fair bit more than just evaporation though. I assume it's not pissing out anywhere else? Had a Golf Mk5 GTI with a thermostat peeing out onto the hot exhaust which instantly evaporated it and the engine fans blowing didn't make it obvious.

21 hours ago, Crackers said:

Might try a new coolant cap before any more drastic measures

Definitely try that. Just to check, I assume it's not fallen apart inside? Again on that Astra H it had and so wasn't holding a pressure. With a thermostat opening temperature of 105c, that car will always boil over without a working cap. 

[N Dentressangle]

9 hours ago, RoverFolkUs said:

@Crackers whereabouts in Sussex are you? From your Jag advert it sounds like we may not be far from eachother at all

I'm in-between jobs at the moment and have the next couple of weeks off. With your utter shit luck with cars, if you get really stuck I'd be more than happy to help another shiter out and take a look at the MG with you to see what it might need and whether I can decipher any signs of OMGHGF? 

Sometimes another pair of eyes with a fresh mindset is all it takes 

Great offer!

Take him up on it. If no joy then either park it up and forget for a while or bin it off. Life's too short.

[Crackers]

18 hours ago, RoverFolkUs said:

@Crackers whereabouts in Sussex are you? From your Jag advert it sounds like we may not be far from eachother at all

I'm in-between jobs at the moment and have the next couple of weeks off. With your utter shit luck with cars, if you get really stuck I'd be more than happy to help another shiter out and take a look at the MG with you to see what it might need and whether I can decipher any signs of OMGHGF? 

Sometimes another pair of eyes with a fresh mindset is all it takes 

That is an exceedingly kind offer, thank you. I'm in Chichester. The only sticking point being that I'm working this week bar Friday, and then off to Munich for work for the next 2 weeks. 

Iirc you're further over Eastbourne way, if I'm not confusing you with someone else - drop me a DM if you fancy it, but absolutely no pressure whatever if it's too far or doesn't line up. 

[Crackers]

9 hours ago, SiC said:

How long are you doing the test for? My instructions say an absolute maximum of 5 minutes as the heat from the coolant will affect the test result colour. I did the test three times (actually four but one I had it too hot and it boiled all it's coolant out) and got the same result.

Yup, about the same, I had to take it out the tank a couple of times as the coolant started creeping into the tube, but wouldn't have been more than 5 mins total. 

I've ordered a new cap today, for the sake of £15 it's worth a try as it didn't exhibit more HGF symptoms when I was looking on Saturday. 

[ruffgeezer]

If that is a cheap block testing kit, be very wary of trusting it.  I've known a place diagnosed a headmaster using one, but then test 3 or 4 other cars on the forecourt all of which showed failure too - and no, it wasn't a Rocer specialist! 

[Talbot]

On 15/02/2026 at 11:11, Crackers said:

Lost several litres of water running it with the cap off (don't how normal that is?) but according to the digital readout on the dash, it never got hotter than 93deg.

It's not normal at all.

I've regularly run cars with the pressure cap loose/removed as there has been a small leak somewhere, and allowing the coolant to pressurise means it jets out rather than just weeping.  Even with a weepy leak somewhere, with no pressure in the system and the cap missing, you'd expect to lose a little bit of coolant.  Maybe a litre for every thousand miles driven.  I've been running the C6 like this for a while as it had a split in the de-aeration chamber, meaning if you pressurise the system, it all leaks out.  But with the pressure cap off, it's a mere dribble.

So, the fact that you lost several litres while running with the cap off for such a short time suggests heavily that you have a leak somewhere.  A big one too.

If you have bought a new cap, a lovely test to do is get the old one, drill out a hole in it, and connect it up to a compressor.  Put 15psi into the top of the header tank on a cold engine, and see what happens.  it will be one of several options:

• You immediately spot a big leak coming out from somewhere obvious.
• You spot a leak that would normally be onto something hot, so it's less obvious.
• You pour a load of coolant into the exhaust manifold : A split EGR cooler is the issue here.
• You hyrdolock a cylinder : HGF mate.
• You notice a weep from a spot on the engine:  Either a split/corroded core plug, or something has gone porous.
• The coolant level stays solid for several hours:  No issues.  Or at least no issue that happens when the engine is cold. 

It's a very powerful test.  Which if you need assistance to run, I'd of course be glad to assist!

[Crackers]

21 minutes ago, Talbot said:

So, the fact that you lost several litres while running with the cap off for such a short time suggests heavily that you have a leak somewhere.  A big one too.

OK, now I'm home I can upload a vid, the coolant does not appear to be coming out anywhere other than here. 

Engine wasn't overly hot when this clip was filmed but the behaviour is more or less the same from cold to operating temp. This is one of the things that suggests to me that a cap won't miraculously make the problem go away. 

If its run with the cap on, when taking the cap off after it cools down there is a bit of pressure behind it but not masses. With the tester in the hole, there's a bit of gas bubbling through the fluid, but not a huge amount. Doesn't seem enough to push so much water out as shown in the video. 

I've not experienced this sort of thing before as obviously all my previous cars have been perfect* and faultless*. 

[SiC]

Are these prone to air locks when bleeding?

I tend to vacuum fill coolant systems nowadays. Bought a kit for £60 off Amazon that also has a pressure test pump. 

Perfect for testing to see if a system holds pressure and also makes filling quick+easy.

 

If it's only bubbling out when hot, I'd strongly think it's not HGF as that should be doing it all the time given an engine is a pump. But never say never with cars I've learnt over the years 🙃

How strong is the coolant now? Again that Astra H would boil over at 100c when it was effectively straight water (as topped up so many times) as obviously that's the boiling point of water which is a lot lower than mixed coolant would be. Evaporation will be more with straight water versus mixed coolant. Also far more likely hot spots that bubble out inside the cooling system if not under pressure.

[SiC]

14 minutes ago, Crackers said:

OK, now I'm home I can upload a vid, the coolant does not appear to be coming out anywhere other than here. 

Engine wasn't overly hot when this clip was filmed but the behaviour is more or less the same from cold to operating temp. This is one of the things that suggests to me that a cap won't miraculously make the problem go away. 

If its run with the cap on, when taking the cap off after it cools down there is a bit of pressure behind it but not masses. With the tester in the hole, there's a bit of gas bubbling through the fluid, but not a huge amount. Doesn't seem enough to push so much water out as shown in the video. 

I've not experienced this sort of thing before as obviously all my previous cars have been perfect* and faultless*. 

To me that looks just as likely an air lock. Googling suggests the KV6 can be a bastard to bleed and is air lock prone with special bleeding procedures. (Or nowadays use a vacuum fill as they're far more affordable than they used to be)

I'd be interested to see what others think.

[SiC]

Googling suggests the KV6 can be a bastard to bleed and is air lock prone with special bleeding procedures.

Christ... 
 

Secondly, with a KV6 you must follow the MGR procedure for refilling as follows:
- Apply Loctite 242 to first three threads of cylinder block drain plug. Tighten to 20 Nm.
- Remove bleed screw from radiator bottom hose.
- Remove bolt securing expansion tank and raise as high as possible (approx. 125 mm).
- Fill cooling system keeping level at expansion tank neck until a steady stream of coolant is emitted from bleed screw hole. Fit and tighten bleed screw.
- Continue to fill expansion tank until level reaches neck and remains static. Refit tank to body, tightening bolt to 5 Nm.
- Press 'Econ' button to switch air conditioning off [this is to prevent the radiator fan from running continuously].
- With expansion tank cap off run engine at 1,500 - 2,500 rpm, filling as necessary to keep coolant level just below expansion tank neck. When level starts to rise, fit cap.
- Continue running engine at same speed until the radiator fan starts, then reduce to idle until it stops. [in practice this may not be achievable, in which case establish that the engine has reached above 90° by activating the IPK diagnostics.)
- Allow the engine to cool for at least 30 minutes and top up the expansion tank no higher than the 'Max' marker. If this is not visible, remove coolant until it is. [in practice, topping-up will be necessary three or four times after a journey.]
You'll need at least 7.5 litres of coolant.

They're also apparently prone to leaking between the V - which I imagine will be hard to spot.

[mercedade]

My W124 260e did very similar with no cap, and with a fully refreshed cap was 100% perfect. 

It scared me at first, but was persuaded that's exactly what it was supposed to do, and why the cap was pressure rater as opposed to an old school expansion tank 

[mercedade]

2 minutes ago, SiC said:

Christ... 🤣

 

The only car harder to bleed than my KV6 ZT190 was my MR2

[Crackers]

48 minutes ago, SiC said:

Christ... 
 


They're also apparently prone to leaking between the V - which I imagine will be hard to spot.

Now where are those spare sets of limbs I leave lying around? 🤣 I count at least four arms and one 10ft leg required to carry out that procedure! 

[N Dentressangle]

1 hour ago, SiC said:

To me that looks just as likely an air lock. Googling suggests the KV6 can be a bastard to bleed and is air lock prone with special bleeding procedures. (Or nowadays use a vacuum fill as they're far more affordable than they used to be)

I'd be interested to see what others think.

I agree - that looks like fairly normal water pump 'surge' to me and possibly an air lock somewhere in the system.

The bad HGF I've seen had bubbles coming up through the tank and a jet of bubbling water shot out when revved! 🤣 That was a P38 V8 with a badly blown HG at any rate.

My 924 did this thing when you switched off it would bubble and boil up, and spit a load of water out of the expansion tank pressure release. Had me slightly worried, but a new pressure cap fixed the problem completely. So it is possible.

[Split_Pin]

I agree theres no bubbles in that, its being purged out somehow.

KV6 is a indeed a twat to bleed, the diesel just as much but as they run cool you can go for a bumpy drive and run the gauntlet against the temperature in diagnostic mode 😂

As said above there's a procedure for bleeding it.

This is exactly the point in 75 / ZT ownership at which you either stay on the light side and get rid of it or come over to the dark side and actually enjoy the misery 😂

[N Dentressangle]

The bleed method as described by Haynes (which apparently works) is:

Remove the bleed screw in the large coolant hose, visible between the engine and air cleaner.
Release the expansion tank bleed hose from top of rad.
Remove expansion tank securing screw and lift clear. Support the tank as high as hoses will allow (about 5"). So that it is the highest point in the system.
Slowly fill the system through the exp tank filler, untill coolant emerges continuosly from bleed screw hole.
Replace the bleed screw.
With the tank still raised, continue filling to a level just below the filler neck.
Refit exp tank and refit bleed hose to top of rad. Leave the filler cap off for now.
Ensure air con is off, and run engine at fast idle (up to 2500 rpm).
Top up as required while heat builds up.
Fit and tighten filler cap.
Run engine until fans cut in.
Swithc off and allow to cool.
When cool, check level and give final top-up.

I'd definitely give that a go before I did anything else. I remember the 1.1 K series wasn't straightforward to bleed either.

[RoverFolkUs]

On 16/02/2026 at 17:51, Crackers said:

That is an exceedingly kind offer, thank you. I'm in Chichester. The only sticking point being that I'm working this week bar Friday, and then off to Munich for work for the next 2 weeks. 

Iirc you're further over Eastbourne way, if I'm not confusing you with someone else - drop me a DM if you fancy it, but absolutely no pressure whatever if it's too far or doesn't line up. 

Ah ok, yeah Chichester is a bit further out than I thought - I'm in mid Sussex just north of Brighton. 

A couple of things I'll mention with rover cooling systems is that when I have bled the 4 cylinder K-Series in the past it has puked out the contents of the expansion tank a number of times before successfully bleeding. 

My solution to this is fill tank to max, start engine with heaters on full heat, hold RPM at a fast idle (2000rpm) until you start to see the level in the header tank rise, once it starts to rise to the top switch the engine off and allow it to settle until the level drops noticeably, refill to max and repeat until you've got consistent heat inside the car. 

Vacuum filling has always been strongly recommended for Rovers because it makes the bleeding process a lot easier, but without that kit to hand I've found the above method works. 

By running the car until the coolant boils over, it's introducing more airlocks. Some people put the cap on at this point thinking it's bled and then carry on driving around thinking they've got OMGHGF because it's overheating and has inconsistent heater temperature (due to the airlock)

[Volksy]

I had a Passat GL5 years back that used to overheat under any sort of load. Would throw out its coolant too. 

My friends old man had a look at it, took the expansion tank cap off, put a clear plastic bag over the filler and screwed the cap back on. Never overheated again.