[Koicarpkeeper]

If your radiator was blocked you would have cold spots on it. My Corsa B decided that it was going to overheat on the way to Alton Towers on one of the hottest days of the year. We had to endure having the heater on full blast to keep the temperature down in the engine. When I checked the radiator it was stone cold over about ¾ if the surface and it weighed a ton when I took it out to change it, from all the build up inside it.
As others have said the Corsa D front end comes off easily and is light enough to manage single handedly. Helps if you have a few old tyres to drop it down onto while you disconnect fog lights if you have them, then the outside temperature sensor. No idea why people think taking the bumper off is such a big deal.

 

[SXI_1.2]

You said you did the litmus test but this will only show if there is anything in the coolant that shouldn't be the head gasket could be on its way but not be putting gas into the coolant, i do hope it turns out to be the radiator but don't understand why two mechanics have missed something so simple, feeling the length of the radiator (fan disconnected) when the engine was up to temperature would have told them for sure.

 

[msgabri]

Yes the blocked radiator should have been picked up earlier both by all those who had a look at overheating issues, and myself I also least thought it can be a blocked radiator as the coolant was very clean. So we all missed it sadly. I took my car to two different garages a week apart for litmus test for HG due to presence of mayonnaise on oil filler cap , both said my HG was fine mayonnaise was most likely condensation which they said was quite common to Vauxhall 1.4 engines.

So I was told that I got to be looking at other issues, they were not asked for their opinions but did suggest it could be fans not coming on early, or a stuck thermostat, so this is why I next removed the thermostat as it is an easy option, after it made no difference fan switching was suspected, as fans appeared to come on too late, looking for a radiator mounted fan switch, but this car did not have one so it relied on engine temperature sensor to kick fans in through ECU, so replaced the engine temperature sensor, it made no difference, so then suspected water pump not pumping, took it to a garage to see how much they would charge and one garage quoted me just £100 with pump supplied I left my car with them to go ahead, asked them to save the old pump, for me to see, it looked fine to me, including bearings, all vanes were fine, so then I realised I had wasted £100, the pump was not needed, so unfortunately it is first time in my driving history of over 50 years that I have come across a blocked radiator, most radiator problems stem from corrosion or leaks. Rarely came across blockages unless the car was not being maintained properly, I bought this car last year from a neighbour and soon it developed overheating issues.

Any way that is aside now, I learned a good deal through mistakes, and as per my title for this thread, I wanted to know if I can do this job myself or will I be better off giving it to a garage to swap the radiator, things that I can see is even if the front is relatively easy to unscrew, and moved out of the way, how easy is the rest of the removal procedure, is there a seperate radiator or heat exchanger for the AC, I have been told that if I start messing about removing the main radiator the AC radiator is also mounted to it and will also require unbolting and any pipes carrying refringent can crack etc, and leak, and I could well get into complications, so this is what I mean to know how big a task is this, what is involved, etc.

 

[SXI_1.2]

 

[msgabri]

Thanks mate for the above, I saw this video when I tried to find out how big a job it was, unfortunately the quality of video was not sharp, still a mammoth effort by the poster, but i wish it was more clear and what I am worried about is accessing pipes clips etc, in confined and tight spaces, from inside, so I am trying to book it with a garage to to do it for me.

My confidence is low doing this job, I done lots of work on cars, I last did a complete cylinder head rebuild on a Vauxhall Calibra,2.0 Ecotec, sent head for resurfacing and all new gaskets and reground valve seats etc, etc, its HG failed and engine went into a hydro lock. but this what should be a simple job is doing my head in.

I appreciate all of your help, some of the information could be useful to others who want to indulge in this, if i have lost my confidence in able to do it right without causing other damage to other parts.

 

[msgabri]

LATEST UPDATE:

Overheating issues on my 1.4 Corsa Automatic.

to save you reading complete thread this is what I diagnosed and changed in order to get to the bottom of the problem in this order:-

1. Expansion bottle filler Cap ( Tried 3 new caps so far as being the cheapest option first)
2.Removed Thermostat altogether, ruling out any problems with it not opening
3.Noticed Fans were cutting in rather seemingly very late once the engine coolant had boiled out through the pressurised cap. Running dry.
4. Radiator fan blowing cold air, indicating radiator is not getting coolant flowing through it so could be water pump issues. ( However I overlooked the fact that once coolant goes out, water pump is devoid of any coolant then it is not going to pump anything, I learned this rather late)
5. Also suspected Head Gasket problems so had 2 sniffer tests carried out at two different garages. Both came with No HG issues.
6. Next I suspected Water Pump, since I was also not getting internal heater giving hot air either to heat interior, it blew cold air even when engine is just warm, so first the water pump was suspected not pumping strong, when that was replaced the internal heating still did not work.
7 So Internal Matrix blockage suspected and removed and flushed with a hose and cleared off any blockages, it then started to give out adequate heat for as long as coolant remained in the system, if once the coolant has spewed out it would blow cold air.
8. Finally thought it may well be the Main Radiator blocked, so had that replaced yesterday with a brand new one, still no joy. Bought another new filler cap, my 3rd cap.

So here is the latest on radiator replacement outcome:
Took the car to a garage to have the radiator replaced with a new one, also asked the mechanic to flush through the hoses and engine block, in case there is any debris and the new rad might become blocked as the old one was highly suspected to be blocked. (not proven but suspected that it was, so for the price of new one under £50, I chose to just replace it)

So after going for a test drive, engine overheated, coolant spewed out, warm air vents started blowing cold air, indicating lack of coolant and circulation.

So I am back to square one, no joy, car still overheating, so bought a third new expansion bottle cap, and still no joy, fan kicks in around 103c-105c , by which time coolant has already spewed out so radiator has no hot coolant flowing through it to cool, as coolant level drops below the water pump impeller.

I had a new water pump supplied and installed by a garage, I was not too sure if they replaced the thermostat, so just for peace of mind 3 screws and I took the thermostat housing out, there is NO Thermostat so no question of thermostat not opening.

But if the fans cut in early, this overheating can be prevented, fans are under the ECU control and relies on Temperature sensor sending a reading to ECU, which fires fan relays. I can cheat or trick the ECU to kick fans in a bit early; by adding a 1K resistor in parallel, but this messes up cold starting as ECU thinks the engine is already at normal temperature so does not send extra fuelling. But once start, car runs sweet and cool.

I also looked at this thread boiling coolant? so it is now evident there is a strange issue with these cars, this poor guy on this thread ended up trading in his Corsa with a different brand car, shame on Vauxhalls for running engine fans too hot.

In a pressurised system, engine does not have to run hotter than about 85c to 90c, that means cooling fan should cut in early, do not forget most Corsa's have a radiator fan switch which, most of these fan switches cuts in at 85c independent of ECU control, my Corsa has no radiator fan switch, so is under ECU control through a engine temperature sensor, so programmed incorrectly (in my view) to bring the fans on too late, since in most other cars fans cut in early, never seen fans cut in over 100c, My own other car a Vauxhall Calibra has a radiator fan switch, a two stage switch, stage 1 fan runs slow through the resistor, when temp hits 83c, and stage 2 fan runs at full speed when engine temp hits 87c, my Calibra never overheated, I bought this Corsa as my Calibra is now subject to dreadful King Khan's ULEZ Charge ! A Pathetic charge if you ask me. However, Vauxhalls must have got it quite wrong on this Corsa, switching fan on when engine is at 105C ! Bad Engineering.

( Incidentally, I brought the old radiator back with me, ran a hose through it, it has no blockage what so ever! ) The whole issue is fans not cutting in early enough to prevent overheating and coolant blowing out.) This is my conclusion, and fortunately I will be able to overcome this by adding some electronic sensing that trips fan relays in early and hopefully prevent these issue. and who knows Vauxhalls are aware of this and have modified fan switch on thresholds in their firmware in the ECU)

Lastly it could well be the Head Gasket.....who knows...
If that fails, dump the car outside the Vauxhall head quarters
( may be there is one more option, try a new expansion bottle ??? may be !)

Other Threads I will be now looking at:
OVERHEATING
TEMPERATURE SPIKE
OVERHEATING ISSUES

 

[SXI_1.2]

In a pressurised system, engine does not have to run hotter than about 85c to 90c, t

that is irrelevant Corsa D run up to 105c thats the way they are designed

However, Vauxhalls must have got it quite wrong on this Corsa, switching fan on when engine is at 105C !

Why have they got it wrong all Corsa D out there are running fine at 105c max with no problems.

Other Threads I will be now looking at:
OVERHEATING
TEMPERATURE SPIKE
OVERHEATING ISSUES

If coolant is boiling you have no pressure in the system you have checked everything you can and its still not working i am convinced you are going to eventually find out its the head gasket but you seem determined to rule that out because of one litmus test.

 

[msgabri]

By comparison, to most other cars even within the Vauxhall range radiator fan should cut in around 85c, especially when stuck in traffic, but here is the thing, when I cheat the ECU into thinking engine has reached 105c when it may be around 70c, I get no issues, as fans kick in early, apart from a side effect of this cheat is cold starting, that I can sort out in another easy way, like add a relay timer that puts that 1K across the temperature sensor after car has started and running for about 2 minutes, and resistor cuts in to bring fans on earlier. I really have already spent endless time and around £120 on new water pump, £30 on 3 new bottle caps, £50 on rad, £10 shipping charge, £120 labour for replacing rad, £50 on new oil and filter as well just in case there was any coolant in oil, but none was evident, so now HG would be very costly affair, i use this car for short journeys, and use my Calibra for long Motorway trips, but I also have access to a Vauxhall Astra 1.4 Turbo satnav 2017, which drives beautifully and never seem to overheat or smell as though it is running this hot as does Corsa, and another friends Corsa runs pretty rough when his engine reaches 103c with fans on.

 

[msgabri]

Why have they got it wrong all Corsa D out there are running fine at 105c max with no problems.

I take your point, the only thing I can now do is to have it pressure tested, see if the system can hold what is it 1 bar pressure over a couple of minutes.

 

[SXI_1.2]

By comparison, to most other cars even within the Vauxhall range radiator fan should cut in around 85c, especially when stuck in traffic,

Why do you keep posting this as if its some kind of fault with the Corsa, i have said several times the corsa D will run up to 105C then the fan will kick in this is how they are designed and they all do it it makes no odds at what temperature you think it should kick in at and at what temperature other VX cars kick in at 105c is the trigger point for the fan its well documented in the forums.

This quote from your last post says it all your system is working properly and the fan is kicking in between 103c and 105c but you have something that is allowing the coolant to boil which usually means you have no pressure in the system hence my suggestion your earlier head gasket diagnosis was wrong.

So I am back to square one, no joy, car still overheating, so bought a third new expansion bottle cap, and still no joy, fan kicks in around 103c-105c , by which time coolant has already spewed out so radiator has no hot coolant flowing through it to cool, as coolant level drops below the water pump impeller.

 

[SXI_1.2]

I take your point, the only thing I can now do is to have it pressure tested, see if the system can hold what is it 1 bar pressure over a couple of minutes.

If money is tight and it is the HG give this a try i have watched several videos where sceptical mechanics have used it and they have been impressed at how good it is like the guy here -

This guy uses a sniffer test but as you say yours passed the litmus test so it may be leaking elsewhere which the pressure test will show.

 

[msgabri]

Believe it or not, I have tried the very thing, it just did not work on mine, I followed instructions meticulously, it cost me £36, I forgot to add this to my expenditure list, so after I emailed the manufacturers, that it did not work on my car, they wrote back that they need a report from a VAT registered garage who diagnosed HG failure, so in other words, this thing would not work or need to not work if you do not have a HG issue, and issues are something else. So basically i cannot make a claim against its 100% guaranteed to work if in the first place my head gasket had no leak, secondly if there were other places where there was a leak, like split hoses, or lose clips, you would see steam or pressure leaking from there. This is why I had two separate sniffer tests carried out at two different garages, each costing £10, again I have not added this to my overall expenditure on this car.

So do I still suspect my HG? I guess I will now have to get someone to carry out pressure test but in the mean time, I have ordered a £3.50 temperature sensor electronic kit from ebay which I intend to wire to switch on the cars' fan relays,hopefully this will stop more drain on my pocket.

Or I could try and get a new expansion bottle, may be the caps do not seal against its mouth, may be.

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-50-110°C W1209 12V Digital Thermostat Sensor Temperature Control Switch Module

which you can set to switch on a relay at any temperature between -50c to +110c, its small steel probe can be clamped to a hot body and relay board mounted in a water tight box, wired to bring on fan relays, independent of ECU switching, this really is how far I can now go,

 

[SXI_1.2]

I really don't know what to think, you said you had a litmus test now you say you had a sniffer test and now you are saying you used steel seal and it didn't work even though you have never mentioned it in the thread, now you are going to spend even more money on some gizmo to trick the fan into turning on to try to mask the real problem, you do realise you could be wrecking your engine by doing this.

As they often say on Dragons Den i wish you luck but i am out.

 

[msgabri]

Sorry mate a sniffer test is what I had meant the word was not coming to me so i used litmus test instead, I had it done twice, a week apart, from two different garages, and yes the Steel Seal thing, I can forward you correspondence with the company, who sent me a claims form as below.

Request for Steel Seal Refund/Replacement

Request is for: Refund / Replacement (delete as appropriate)

Name​	​
Address​	​
Telephone No​
Email​

Date of Purchase​
Date Refund/Replacement Requested​
Registration No​
Make​
Model​
Mileage​

Documents required:

• Proof of Purchase from one of our listed stockists

Also please supply one of the below: (please tick document supplied)

• A statement from a VAT registered garage, that via compression or gas test your vehicle has definitely blown a head gasket
• Confirmation that the vehicle has been scrapped
• Invoice that shows a mechanical head gasket repair has subsequently been carried out (we will also accept a recovery service breakdown report)

Refunds only:

Amount of Refund Requested​

Terms - Only 1 Refund per vehicle. Recommended amount of Steel Seal must have been used. Steel Seal comes with a lifetime guarantee, all we need is this form completed and sent back to us with required information above.


Correspondence below:
Begin forwarded message:

From: Lauryn Webb <[email protected]>
Date: 5 December 2022 at 10:09:42 GMT
To: BLOCKED (ME)
Subject: Re: Fwd: Gurarantee

Good morning,
Please fill in the attached claim form and return this, along with proof of next steps.
Kind regards

On 02/12/2022 22:45, BLOCKED (ME) wrote:

Begin forwarded message:

From: [email protected]
Date: 2 December 2022 at 18:05:24 GMT
To: BLOCKED (ME)
Subject: Re: Gurarantee

Hi,
I can see you are from the UK. Please email [email protected]
They will be able to help you. You have come through to the US customer service.
Hope this helps.
Kindest Regards
Kenzie

On 2022-12-02 12:23, BLOCKED (ME) wrote:

I bought steel seal for my car to stop loss of coolant I followed the instructions from bottle and from YouTube but it didn't work .
I purchased my Steel Seal from
Motor Parts Direct on 30/11/22 it is under Guarantee.
My Car Reg No BLOCKED
Regards
BLOCKED
<image0.jpeg>

 

[msgabri]

So nothing in this I am making up, only that I realised I cannot make this claim as none of the sniffer tests were positive for a failed HG, not any compression tests were carried out, so my claim will get rejected so I never mentioned or needed to mention since if HG is not leaking this sealant is not going to do its job.

But many thanks, i appreciate all help received on these forums, it is really doing my head in, like the other owner who exhausted all avenues and his car would not stop overheating, in the end you can read what he did with his Corsa, traded in with another make of car, (See Bubbling Coolant Thread)

Whilst I have not fully given up, at least with some mods to kick in fans earlier than 105c I will be able to use my car as opposed to not at all, I fully understand you saying these cars kicks cooling fans in at 105c, they run quite hot, that is how they had been intended, and you can see the consequences of any variation in pressure or if the pressure leaks the coolant boils out leaving nothing to pump any more coolant through the radiator to cool the engine down, this to me is an overlooked issue, coolant would not gush out if fans came in early and kept engine temperature well below 90c just 10 degrees short of water boiling point under atmospheric pressure, ( this is my opinion, I may be wrong) so when I tried this mod, the fans kicked in around 75c and the car ran for hours and it did not overheat.

So needless to say more, I will keep others posted as there are perhaps other things I may well have overlooked, such as leaks in the auto transmission fluid plated heat exchanger, I could be losing coolant or pressure through it into auto transmission oil or oil into coolant, but there were no sign of oil in coolant. I must admit I have not suspected it so far, neither have I checked transmission fluid to see for any signs of coolant. So I will for now keep an open mind, any new findings I will post here to help others who may be having similar issues.

I few weeks ago, I saw one owner selling his Corsa very cheap on Ebay motors, stating it has overheating issues hence why he is selling it dirt cheap.

But please remember I did join these forums to seek help, after getting no where, I was hopeful that some light may shine, as you have seen I have now tried most things and except for a brand new expansion bottle, new filler caps, check plated heat exchanger and any other signs of leaks, what else can i do, if I contemplate head gasket and if it wasn't the issue I will be going round in circles.

Just one more thing I know about the history of this car is its previous owner had swapped the engine from a scrap car as his original engine blew up. (not much more information other than this)

A BASIC TEST FOR HEAD GASKET LEAKING COMBUSTION GASSES INTO COOLANT
I am not sure how reliable this test is, you fill up your reservoir bottle to brink, start engine, no bubbles should emerge, if they do it indicates combustion gasses are leaking past the gasket seal. SO this test I have carried out a number of times, no bubbles emerge.

 

[msgabri]

Sorry SXI_1.2, I really appreciated every bit of help I could get, I really needed to get to the bottom of this, its doing my head in too, that is the reason I have come here, the last thing I want to do is modify sensor response to cheat ECU, I perfectly understand you said these cars run hot at 105c when the fan kicks in, that is fine, if that is how Vauxhalls intended, but you can see the consequences of any deviation in designed pressure and fan kick in temperature, could lead to disastrous results such as overheated and warped head or blown head gaskets, costing tons of money to put right, I showed my car to many experts as well, no one could point to any specific cause, yes two of them did suggest I replaced the bottle cap, this is why I took their advise and did that, today I done the same the 3rd time, in another thread mentioned above (Bubbling Coolant) one owner got rid of his car in the end after exhausting all avenues, as no one could get to the bottom of it, he swears never to buy another Vauxhall. But I have not yet given up, and would like to as a last resort try my trick, and it may just work as I won't be running it too hot, why does it need to run that hot? (105c)

The "sniffer test" is what I had meant in my posts, the word was just not coming to me so i used "litmus test" or even "acid test" instead, I had it carried out two different times one week apart, at two different garages, and yes the Steel Seal thing is what one garage suggested I tried, and I did, it is real, just last month I tried but unfortunately it did nothing for me, so I wrote to them seeking refund, I can forward you the correspondence with them, but they asked for a proof of my HG being diagnosed as leaking, from a proper garage with VAT registration being their specific requirement.

This is why I did not mention about the Steel Seal, as my head gasket was not faulty otherwise it would have sealed it, if there were no issues with HG then this product would not have done anything to a good sound HG. That makes sense, so unfortunately I will not be able to claim my £36 I spent on Steel Seal.

So you done your best, many thanks for that, yes you have convinced me there has to be or must be leaks somewhere else, so I will look into that, where it might be, I don't know, could well be the plated heat exchanger that cools auto transmission fluid? You never know what i might find.


HAPPY NEW YEAR EVERYONE> LATEST LONG DRIVE TEST IN TOWN
Car stayed cool, engine never heated up enough to kick fans in, interior heated comfortably, thermostat is completely out, I didn't plug in my OBDII adaptor to monitor maximum temperature engine reached, but just in case it did reach around 85c I my 2.2K resistor is a trade off between cold starting and fans cutting in early, not letting engine boil. This way at least I can use my car and not having to carry a jerry can of water to top up every few miles, I did a run of 10 miles, mixed driving. Car drove really smooth.

I will be honest, if car starts to overheat again, or lose coolant , I shall come back here and report that my mod putting a 2.2K across temperature sensor failed to mask the actual problem i.e compensating for loss of pressure in the cooling system and causing it to overheat or boil coolant dry.

 

[msgabri]

Why do you keep posting this as if its some kind of fault with the Corsa, i have said several times the corsa D will run up to 105C then the fan will kick in this is how they are designed and they all do it it makes no odds at what temperature you think it should kick in at and at what temperature other VX cars kick in at 105c is the trigger point for the fan its well documented in the forums.

This quote from your last post says it all your system is working properly and the fan is kicking in between 103c and 105c but you have something that is allowing the coolant to boil which usually means you have no pressure in the system hence my suggestion your earlier head gasket diagnosis was wrong.

SXI_1.2, I am indebted to you Sir, thank you for emphasising the fact coolant would indeed boil at much lower temperature and escape and leave vacuum i.e. no water to pump, hence all diagnoses were mislead that water was not flowing, how would it if all the coolant had boiled dry and escaped and pump is just turning air !

So this lead to me believing it had something to do with water pump, when that was replaced, engine still boiled over, so then main radiator was suspected to be blocked and it was wrongly diagnosed, since no coolant is flowing through it as there wasn't any left in the engine to be pumped !

HD sniffer tests revealed that there were no issue with it, even tried in vain Steel Seal and that didn't help either as there was nothing wrong with my Head gasket that this product could seal, not knowing Vauxhall Corsa fan switching thresholds, I assumed they were turning on far too late, so tried to bring fan kicking thresholds down to about 80C from the usual 105c, hence my temporary solution to overcome overheating worked to a certain degree, but coolant would still need replenishing every few days as opposed to every trip.

So finally your post really did have an impact on my thinking, you did emphasise that pressure must be leaking from somewhere, you pointed Head Gasket, yes I agree most likely place hidden away from sight, one can see any external leaks, like lose hose clips, leaking expansion bottle, cracks in coolant pipes, radiator itself, and so on, yet nothing was visible,so you suspected misdiagnosed Head gasket.

I then saw other videos on overheating issues, by far the most important thing I came across was pressure testing, yet none of the experts I consulted offered to pressure test the system, they all suggested that i change my radiator cap, for obvious reason that it may not be holding pressure or sealing well.

So finally I focused on pressure testing, I then used one of the old caps and drilled a hole through it to insert a small pipe through which I could pump air pressure to about 10psi, I went up to 15psi, the pressure seem to be holding well, but I could hear a strong hissing from the cap itself, then it transpired that cap O ring seal was not making a good strong seal with the plastic expansion bottle, I then took one of my new caps my 3rd one, and had the white PTF plumbing tape wrapped around the O ring, laid several layers of this PTF tape, and refitted the cap, and done a drive test, with OBDII plugged in to check engine temperature, all was now well, fans kicked in at 105c, pressure was holding, coolant was no longer boiling, and spewing out, engine reached 110c then started to cool down to about 85c and I was pleased the problem has been arrested.

So it turns out to be the bottle neck, all those new caps I bought were not making a good seal with the old bottle so I have now ordered a brand new GM genuine expansion bottle and a new matching cap, I drove my car to work and back it had not used any more coolant or lost any, so a simple thing like that took ages to get diagnosed.

So if a garage had conducted a pressure testing, this problem may have been arrested much earlier and money saved. So too late now and hopefully lessons can be learned from this, I would now recommend people with similar overheating issues to check their bottle as well as cap seals. Just getting a new cap may not always do the trick.

Some even suggested to get a genuine GM cap, but I was too lazy to go to a dealer, plus the fact they tend to rip us out.

I also looked at what pressure the coolant would boil if it was under 10psi, the figure I got for water only as 116c and it may boil even at higher if it has chemicals mixed with it like anti-freeze and rust inhibitor.

In the end this was a massive learning curve.

 

[SXI_1.2]

In the end this was a massive learning curve.

So it turns out to be the bottle neck, all those new caps I bought were not making a good seal with the old bottle so I have now ordered a brand new GM genuine expansion bottle and a new matching cap, I drove my car to work and back it had not used any more coolant or lost any, so a simple thing like that took ages to get diagnosed.

Glad you finally got it sorted and thanks for posting your fix it may help other members in the future.

 

[msgabri]

I hope this pressure testing should be highly recommended along with head gasket tests with a sniffer test, have a look at this overheating thread Overheating This poster has also somewhat been thorough what I went through, yet no one suggested him about pressure testing, may be SXI_1.2 you could post something about pressure testing and look into his coolant bottle sealing with caps being the weakest link.

 

[Tommygards]

Glad you got it sorted 👍 not done one recently but ironically pressure testing is normally done by removing the coolant reservoir cap and fitting a different one that comes with the pressure kit that allows you to apply pressure via the cap…so even a pressure test may not have identified a poorly sealed cap.