coolent leak !?

[Mgaz]

:(

Just took the misses to work 10 minutes down the road, got back and noticed a puff of steam coming from the front of the bonnet as i parked up.

Turned engine off immediately and popped the bonnet to find coolant over the sides of the expansion tank and sprayed on to various other areas.

Temperature gauge was normal dead in the centre.. But I did think id lost a little coolant the other day when i checked the level in the morning. And ironical id bought some OAT to top it up with. Was going to top it up this morning but forgot. It was only on the minimum mark when i checked it yesterday.


Hope the engine is okay.. :(

why would it have spat it out of the expansion tank ?

[suzublu]

Forget the temp gauge, useless until too late, use this to monitor correct temp https://the75andztclub.co.uk/forum/showthread.php?t=55585
Your cap seals may be goosed due to overtightening, replacement viton ones can be found on EBay. Be sure you don't overfill the tank;)

[Yorkshire GOC]

:(

Just took the misses to work 10 minutes down the road, got back and noticed a puff of steam coming from the front of the bonnet as i parked up.

Turned engine off immediately and popped the bonnet to find coolent over the sides of the expansion tank and sprayed on to various other areas.

Temperature gauge was normal dead in the centre.. But I did think id lost a little coolent the other day when i checked the level in the morning. And ironical id bought some OAT to top it up with. Was going to top it up this morning but forgot. It was only on the minimum mark when i checked it yesterday.


Hope the engine is okay.. :(

why would it have spat it out of the expansion tank ?

I have had a failing cap - lost 1.5 litres and my HG as a consequence. From what you say you have not gunned her or lost much coolant so should be ok. Try the T Cut test - take her out and give her 20 mins of dual carriageway at speed - leave to next morning and open the expansion cap - if no pressure then fine ie no whoosh or hiss from the tank - if there is pressure it points to exhaust gases in the coolant system:shrug:

Since my cap issue i swop my cap out every 12 months and fitted one of these - gives you control over temperature issues - took Trikey 45 mins to fit and can be done DIY as well.

https://www.ebay.co.uk/itm/E-Zee-K-Bus-Digital-Temperature-Gauge-for-Rover-75-MG-ZT-DIY-Self-Fit-Kit/132359953363?hash=item1ed1449bd3:g:m1cAAOSwtfhYsZw N

[Mgaz]

I have had a failing cap - lost 1.5 litres and my HG as a consequence. From what you say you have not gunned her or lost much coolant so should be ok. Try the T Cut test - take her out and give her 20 mins of dual carriageway at speed - leave to next morning and open the expansion cap - if no pressure then fine ie no whoosh or hiss from the tank - if there is pressure it points to exhaust gases in the coolant system:shrug:

Since my cap issue i swop my cap out every 12 months and fitted one of these - gives you control over temperature issues - took Trikey 45 mins to fit and can be done DIY as well.

https://www.ebay.co.uk/itm/E-Zee-K-Bus-Digital-Temperature-Gauge-for-Rover-75-MG-ZT-DIY-Self-Fit-Kit/132359953363?hash=item1ed1449bd3:g:m1cAAOSwtfhYsZw N


Oh dear... Is the tolerance of the engine really that low?

Hope the head gasket isn't damaged :( , I shall be gutted if it is.



I wonder, could a larger expansion tank be fitted to increase the coolent capacity and lower the risk of over heating from a small amount of coolent loss?

:(

[LeRich]

I wonder, could a larger expansion tank be fitted to increase the coolent capacity and lower the risk of over heating from a small amount of coolent loss?:(

You could possibly fit a larger tank if you can find one that fits a suitable void in the engine bay. You'd be better off fitting a low level sensor or just keeping a close eye on the level. I check mine weekly as I have a slow weep on my IMG and need to occasionally add a few ml to keep the level correct.

[Mgaz]

Since my cap issue i swop my cap out every 12 months

where do you buy your new caps from?

might just order a new one before driving it again.

EDIT: apparently there seems to be two different caps. Rated at different release pressures for diesel or petrol engines. So need to make sue I get the right one.

[kaiser]

Could we have a moderator correct the speeling in the headline, please:}
A larger coolant tank does nothing to alleviate the problem.
Just ongoing vigilance, and any gadget that will warn you of water loss!
These engines need nursing like a baby, and can go from hero to zero in a very short time.
Check your fan, for starters.

[NigelOBB]

I have had a failing cap - lost 1.5 litres and my HG as a consequence. From what you say you have not gunned her or lost much coolant so should be ok. Try the T Cut test - take her out and give her 20 mins of dual carriageway at speed - leave to next morning and open the expansion cap - if no pressure then fine ie no whoosh or hiss from the tank - if there is pressure it points to exhaust gases in the coolant system:shrug:



Since my cap issue i swop my cap out every 12 months and fitted one of these - gives you control over temperature issues - took Trikey 45 mins to fit and can be done DIY as well.



https://www.ebay.co.uk/itm/E-Zee-K-Bus-Digital-Temperature-Gauge-for-Rover-75-MG-ZT-DIY-Self-Fit-Kit/132359953363?hash=item1ed1449bd3:g:m1cAAOSwtfhYsZw N



I picked up one of these, https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F 232523265551
Just plugs straight into your OBD port.. put temp right in front of your face lol


Sent from my iPhone using Tapatalk

[SD1too]

Gareth; keep this in perspective and don't buy anything until we've diagnosed the problem.


Fill the expansion tank to the 'max' mark.
Carry out the 'demist test' to check that your fan is running on slow speed.
If it is, activate the instrument pack diagnostics to monitor the actual coolant temperature. The gauge is useless.
Report back.


Have you had any work done on the cooling system recently?

why would it have spat it out of the expansion tank ?
Because the coolant overheated.

Simon

[minimutly]

I picked up one of these, https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F 232523265551
Just plugs straight into your OBD port.. put temp right in front of your face lol


Sent from my iPhone using Tapatalk

So can you reccommend this gismo - how long have you used it?
Thanks.

[Mgaz]

Okay.. Cheers for the replies so far.

I do remember something being mentioned about the fan speed when i bought the car. We were sitting in the car and being showed the temperature controls and de-mist function.

In my ignorance I thought he was on about the fan for the interior cabin.

Im guessing then, this means the radiator fan is goosed ?

The car is at home at the moment and i am not, so i can't do the checks mentioned above right at this moment in time.

So.. Im guessing Im in need of a replacement fan? If anybody's got one?

On a side note, if it makes a difference.. I only just worked out how to turn the aircon off and have been driving with the car in ECON mode.

Could this have had the side effect of the fan staying off? And the engine over heating?


Gareth; keep this in perspective and don't buy anything until we've diagnosed the problem.


Fill the expansion tank to the 'max' mark.
Carry out the 'demist test' to check that your fan is running on slow speed.
If it is, activate the instrument pack diagnostics to monitor the actual coolant temperature. The gauge is useless.
Report back.


Have you had any work done on the cooling system recently?


Because the coolant overheated.

Simon

[Yorkshire GOC]

Assuming your fan does not pass the demist test.

When looking through your grill at the front RHS you will see the fan - if you see a silver coloured resistor on the fan this is a classic fan failure point and folk replace it with the upgraded gold resistor. You can get those on E bay.

As to coolant caps you need the 140 PSI type - they are clearly marked 140 psi on the underside of the cap.

[Lord of Hog]

I've got the digital temperature gauge ... it just gives me one more thing to be paranoid about!

[Yorkshire GOC]

Oh dear... Is the tolerance of the engine really that low?

Hope the head gasket isn't damaged :( , I shall be gutted if it is.



I wonder, could a larger expansion tank be fitted to increase the coolent capacity and lower the risk of over heating from a small amount of coolent loss?

:(

The 1.8T/1.8 is most prone to HG problems and needs watching like a hawk - the V6 is considered less prone to HG issues - i suppose one reason being a V6 has a larger coolant volume than a 1.8.:shrug:

[Mgaz]

Assuming your fan does not pass the demist test.

When looking through your grill at the front RHS you will see the fan - if you see a silver coloured resistor on the fan this is a classic fan failure point and folk replace it with the upgraded gold resistor. You can get those on E bay.

As to coolant caps you need the 140 PSI type - they are clearly marked 140 psi on the underside of the cap.

Im sure i found a post on the dot org forum that stated the 140cap was for use on the diesel?

Also said that the 140 marking wasn't a psi rating.and its about 23psi or something?

[Yorkshire GOC]

Hi,

The 140 cap is what you need - certainly on a petrol car ( i think its the same for the diesels as well anyway - but no doubt someone with a diesel will confirm this ) - but that is the Spec you need - see link below;)


http://www.ebay.co.uk/itm/New-Radiator-Pressure-Expansion-Water-Tank-Cap-For-MG-ZT-Rover-75/361619770046?epid=1675236641&hash=item543237cabe:g:GZIAAOSwH05ZuxSg

[T-Cut]

The '140' cap (that's kiloPascals, not PSI - it's about 22psi), is now the standard for all engines.

TC

[Mgaz]

The '140' cap (that's kiloPascals, not PSI - it's about 22psi), is now the standard for all engines.

TC

Thanks T-Cut , your names been mentioned a few times on here and dot Org :)

I've also found a 140 cap from here : https://www.eurocarparts.com/ecp/c/MG_ZT_2.5_2002/p/-/-/-/-/?204110040&1&e887eb5780256f1f28650f0598dd9283ad6c5136&000263

but the picture looks strange? what Am I looking at? is it a BMW expansion tank? :shrug:

Anyway, as long as its the right thing, I'll buy a new cap to be on the safe side.

[Yorkshire GOC]

Hi,

The 140 cap is what you need - certainly on a petrol car ( i think its the same for the diesels as well anyway - but no doubt someone with a diesel will confirm this ) - but that is the Spec you need - see link below;)


http://www.ebay.co.uk/itm/New-Radiator-Pressure-Expansion-Water-Tank-Cap-For-MG-ZT-Rover-75/361619770046?epid=1675236641&hash=item543237cabe:g:GZIAAOSwH05ZuxSg


The cap advertised on the above link is what you need ;)

[suzublu]

Thanks T-Cut , your names been mentioned a few times on here and dot Org :)

I've also found a 140 cap from here : https://www.eurocarparts.com/ecp/c/MG_ZT_2.5_2002/p/-/-/-/-/?204110040&1&e887eb5780256f1f28650f0598dd9283ad6c5136&000263

but the picture looks strange? what Am I looking at? is it a BMW expansion tank? :shrug:

Anyway, as long as its the right thing, I'll buy a new cap to be on the safe side.

Nooo, that's not right:duh: https://www.dmgrs.co.uk/products/rover-75-mg-zt-coolant-cap-oem-esr1480-fits-all-petrol-diesel

[Mgaz]

Have you had any work done on the cooling system recently?

Simon

P.S the car is new to me as of Saturday 20th of January. So I'm still just getting acquainted with it and I've not owned a ZT/75 before either. And I've had no work done to the car at all yet.. apart from changing the head unit.

[Mgaz]

Nooo, that's not right:duh: https://www.dmgrs.co.uk/products/rover-75-mg-zt-coolant-cap-oem-esr1480-fits-all-petrol-diesel

cheers.. though it says postage is £4.99 on top
Where as the ebay item linked to by Yorkshire GOC has free postage.

Anybody had any bad experience with the ebay ones?

[suzublu]

Just replace the rubber seals https://www.ebay.co.uk/itm/Rover-75-MG-ZT-Coolant-Pressure-Cap-VITON-O-Ring-Seals-Expansion-Header-Tank/132484862055?hash=item1ed8b69067:g:Rv0AAOSweW5VXOL W
Sorry to bombard you with options, just trying to help:o I know you'll feel confused a bit as a new owner, but it'll all come out in the wash:D

[Mgaz]

Just replace the rubber seals https://www.ebay.co.uk/itm/Rover-75-MG-ZT-Coolant-Pressure-Cap-VITON-O-Ring-Seals-Expansion-Header-Tank/132484862055?hash=item1ed8b69067:g:Rv0AAOSweW5VXOL W
Sorry to bombard you with options, just trying to help:o I know you'll feel confused a bit as a new owner, but it'll all come out in the wash:D

okay.. I might just do that. But I will first check that I have the correct 140 spec cap before I do decide.

[suzublu]

okay.. I might just do that. But I will first check that I have the correct 140 spec cap before I do decide.

Just look under the cap, it's marked:cool:

[Mgaz]

Just look under the cap, it's marked:cool:

Will do once I'm back home..

I suppose I could try asking the misses to check it out, but her likely response would be "eh!?" :D

[suzublu]

Land Rover caps fit too;):D

[stevestrat]

Anybody had any bad experience with the ebay ones?YES! I had a cap I suspected was allowing coolant past the seals, made the mistake of buying one from Ebay and it was worse than the one it was supposed to be replacing. Buy from a known seller such as DMGRS.

[Mgaz]

YES! I had a cap I suspected was allowing coolant past the seals, made the mistake of buying one from Ebay and it was worse than the one it was supposed to be replacing. Buy from a known seller such as DMGRS.

cheers! :)

Do the caps from DMGRS come with viton o ring seals? what ever 'viton' is ? :cool:

[suzublu]

Viton doesn't compress a much as ordinary rubber, much slippier too:cool: I always apply a little vaseline to them before tightening the cap;):D

[stevestrat]

cheers! :)

Do the caps from DMGRS come with viton o ring seals? what ever 'viton' is ? :cool:

I doubt it but he does sell viton O rings (https://www.dmgrs.co.uk/collections/thermostats-and-waterpumps/products/rover-75-mg-zt-coolant-cap-o-rings-viton-to-fix-esr1480).

[Mgaz]

Land Rover caps fit too;):D

Cheers for that!.. I've also read about fitting a BMW 200 pressure spec cap? Thus giving a higher temperature before boiling occurs. :shrug:

Yay or Nay?

[SD1too]

Im guessing then, this means the radiator fan is goosed ?
Don't guess, do the 'demist test' and find out for sure.
So.. Im guessing Im in need of a replacement fan?
Don't guess! Do the 'demist test' and if the slow speed isn't working the next step is to find out if you have a resistor in the fan circuit (as previously described). If you do, then you most likely need a new resistor NOT a new fan.
... I only just worked out how to turn the aircon off and have been driving with the car in ECON mode. Could this have had the side effect of the fan staying off? And the engine over heating?
No. Whether the air con. is on or off makes no difference to overheating.

Simon

[Mgaz]

Well I've done the demist test...
If I've done it right, the result is not looking too good :(

Also, I can't seem to see where this resister is supposed to be?


MG ZT 190 kv6 Demist test. Fail: https://youtu.be/8GRwVhGZYM4

Don't guess, do the 'demist test' and find out for sure.

Don't guess! Do the 'demist test' and if the slow speed isn't working the next step is to find out if you have a resistor in the fan circuit (as previously described). If you do, then you most likely need a new resistor NOT a new fan.

No. Whether the air con. is on or off makes no difference to overheating.

Simon

[suzublu]

https://www.the75andztclub.co.uk/forum/showthread.php?t=68336

[SD1too]

Well I've done the demist test...
If I've done it right, the result is not looking too good
Brilliant video Gareth which shows that your slow speed has failed. This is very common so don't worry. I've had it and so have many other club members.
Also, I can't seem to see where this resistor is supposed to be?
Have a look at these photographs (https://the75andztclub.co.uk/forum/showpost.php?p=1370153&postcount=4) from Arctic which should help.

Simon

[Mgaz]

Brilliant video Gareth which shows that your slow speed has failed. This is very common so don't worry. I've had it and so have many other club members.

Have a look at these photographs (https://the75andztclub.co.uk/forum/showpost.php?p=1370153&postcount=4) from Arctic which should help.

Simon

Thanks!.. Will have another look in the morning. Though mine is a 2002 model ZT , so Im guessing it will have the 3 speed fan and no resister ???

Can this gold resister be fitted to a 3 speed fan without one already there?

How do i test to see if the fan is working at all?

Is there a wire i can easily connect direct to a battery to make sure?

[SD1too]

So many questions! :D
... mine is a 2002 model ZT , so Im guessing it will have the 3 speed fan and no resister ?
Don't guess! :twonk: It may have had a 3 speed system from new but there's no telling what Mr. Previous Owner and/or his garage may have done. The way to tell is to look for the resistor on the fan shrouding.
Can this gold resister be fitted to a 3 speed fan without one already there?
No. The three speed circuit doesn't need a resistor.
How do i test to see if the fan is working at all?
By performing the 'demist test' you have done all that is required. Repairs are necessary.
Is there a wire i can easily connect direct to a battery to make sure?
No. You have already "made sure" by performing the demist test.

So Gareth, look carefully to see if there is a resistor fitted. If not, it's likely that you have a 3 speed system. If you're DIY minded and don't mind wielding a soldering iron, you can fit new brushes for the price of a round of drinks. Otherwise contact Arctic who may well have a refurbished 2 speed system (with gold resistor already fitted) which you can just plug in. It is necessary to remove the front bumper and headlamps though whatever you do.

Next question please Gareth! ;)

Simon

[kelvo]

So many questions! :D

Don't guess! :twonk: It may have had a 3 speed system from new but there's no telling what Mr. Previous Owner and/or his garage may have done. The way to tell is to look for the resistor on the fan shrouding.


Simon

It's my ex-car so I know that it still has the original three speed fan fitted, of which the medium speed was still working.

[SD1too]

... the medium speed was still working.
Was the low speed still working when you sold it Kelvin?

Simon

[Mgaz]

Okay.. Just had a look where i was directed.

I see an attachment area at the 2'o clock position, but sadly no resister.


So looks like it is a 3 speed fan as stated by kelvo .

As for testing it with a battery, i was only asking because what if the problem was a relay? Or a broken wire somewhere?

Im sure you are right though.. But having had wires chewed by rats on my audis in the past, it can be a cause for electrical problems.



So many questions! :D

Don't guess! :twonk: It may have had a 3 speed system from new but there's no telling what Mr. Previous Owner and/or his garage may have done. The way to tell is to look for the resistor on the fan shrouding.

No. The three speed circuit doesn't need a resistor.

By performing the 'demist test' you have done all that is required. Repairs are necessary.

No. You have already "made sure" by performing the demist test.

So Gareth, look carefully to see if there is a resistor fitted. If not, it's likely that you have a 3 speed system. If you're DIY minded and don't mind wielding a soldering iron, you can fit new brushes for the price of a round of drinks. Otherwise contact Arctic who may well have a refurbished 2 speed system (with gold resistor already fitted) which you can just plug in. It is necessary to remove the front bumper and headlamps though whatever you do.

Next question please Gareth! ;)

Simon

[SD1too]

... what if the problem was a relay? Or a broken wire somewhere?
You'll need the bumper off anyway to check both these possibilities. The favourite however remains a worn down motor brush. The relays are very reliable and only the diesel seems to suffer from wiring damage.

Simon

[Mgaz]

It's my ex-car so I know that it still has the original three speed fan fitted, of which the medium speed was still working.

You'll need the bumper off anyway to check both these possibilities. The favourite however remains a worn down motor brush. The relays are very reliable and only the diesel seems to suffer from wiring damage.

Simon


Well, today I shoved a paper clip into the plug on the air con pipe. And after starting the engine and pressing the demist switch, the fan fired up! (is this the 'highest' speed ?)

So,.. looks like I finally found a use for this guy after all! :D
http://i0.kym-cdn.com/entries/icons/facebook/000/001/180/clippy.jpg

[Mgaz]

What fan speed would i have been seeing when it was engaged with the paper clip in the trinity switch? High, medium or low?

:)

[Arctic]

What fan speed would i have been seeing when it was engaged with the paper clip in the trinity switch? High, medium or low?

:)

Hi Gareth.
You would have initiated the high speed, as we know your low & medium speed are not working, I have replied to your email and am trying to sort out a day for you asap, I also have lots of Viton coolant O-rings FOC as these are fitted to every coolant cap on members cars that come to the nano meets ;) Arctic

[SD1too]

What fan speed would i have been seeing when it was engaged with the paper clip in the trinity switch? High, medium or low?
On a 3 speed system the trinary switch triggers the medium speed.
You would have initiated the high speed, as we know your low & medium speed are not working ...
Do we Steve? Can you keep me up to date with any tests carried out not reported in this thread? :}

Simon

[Mgaz]

On a 3 speed system the trinary switch triggers the medium speed.

Do we Steve? Can you keep me up to date with any tests carried out not reported in this thread? :}

Simon

oh.. If that's the medium speed, then would/should the medium speed have been enough to prevent over heating?

Should i be worried something more serious could have forced the coolant out of the cap ?

Or, Maybe the cap was to blame after all?

[SD1too]

Gareth,

You need to get your fan working on all speeds before making any other decisions or suspecting any other components.

Simon

[Mgaz]

Gareth,

You need to get your fan working on all speeds before making any other decisions or suspecting any other components.

Simon

okay.. so if the demist test showed no low speed, and the paper clip test showed medium speed was okay.. how do I test the highest speed?

[T-Cut]

okay.. so if the demist test showed no low speed, and the paper clip test showed medium speed was okay.. how do I test the highest speed?

Read this: https://www.the75andztclub.co.uk/forum/showthread.php?t=35567

You could also disconnect the coolant sensor connection. This will (should) trip on the fan at maximum speed. But worn away motor brushes affect everything.

TC

[SD1too]

.. so if the demist test showed no low speed, and the paper clip test showed medium speed was okay.. how do I test the highest speed?
According to your evidence your motor won't be running at medium speed, you will get low speed because one +ve brush is out of service. High speed demands two +ve brushes and two -ve brushes but your motor cannot provide that so high speed will not be available to you. You cannot easily test it, but there is no point anyway. You need to stop testing and start repairing! :D
You could also disconnect the coolant sensor connection. This will (should) trip on the fan at maximum speed.
Not on a 3 speed system. It triggers medium speed.

Simon

[Mgaz]

[QUOTE]]

Hi Gareth.
You would have initiated the high speed, as we know your low & medium speed are not working, I have replied to your email and am trying to sort out a day for you asap, I also have lots of Viton coolant O-rings FOC as these are fitted to every coolant cap on members cars that come to the nano meets ;) Arctic


well.. A small road trip today and a big thank you to Arctic for fitting a refurbished 2 speed fan to my ZT .

Cheers! Was good to meet you btw!

[Arctic]

Hi Gareth.
After you left and i cleaned up i managed to open your fan motor, as you can see from the photo's below the low speed brush had worn down so much that it would have hardly been touch commutator.

Four wire 3 speed V6
https://i.imgur.com/7iiSyNhm.jpg1

https://i.imgur.com/sSnSrSvm.jpg2

Metal lid/cover removed brush off debris.
https://i.imgur.com/CyibBwSm.jpg3

Remove the brush holding disc
https://i.imgur.com/v1Z5cH4m.jpg4

Turn over the disc to reveal the brush holders.
https://i.imgur.com/Gtoy5j5m.jpg5

I then removed the socket i use to keep brushes in place.
https://i.imgur.com/rxVorMOm.jpg6

You can see from this photo that the low speed is worn right down and the medium as also been worn down which is what happens 95% of the time, i have seen both these brushes worn down so much that it as damaged the commutator
https://i.imgur.com/beMKZgam.jpg7

High speed as been invoked at sometime as they to are worn.
https://i.imgur.com/utjUcxhm.jpg8

Commutator is not in bad shape so will come in useful
https://i.imgur.com/oQqB5PQm.jpg9

There you have it now you know why your fan was not working on low speed
https://i.imgur.com/KPWOXjcm.jpg10

Your two wire 2 speed gold resistor fan that you now have fitted works perfect reaches 100, then low speed kicks in brings it down to 95 as it should, which as you know we checked a few times.

Don't forget to sort out those Vis motors contact Mr Vis (stocktake) he will get you sorted out then you will know how your car runs properly ;) cheers Arctic.

https://the75andztclub.co.uk/forum/private.php?do=newpm&u=1623

[Mgaz]

Cheers again Arctic.. And thanks to everybody else who have given their input . I've one less thing to be paranoid about now. :D

it's much appreciated . :)