mgzt 180 auto: oil in the water and in the V

[simon74]

Hi all, I have just bought a 2003 mgzt 180 auto in le mans green, I bought it as a non runner . the previous owner says it had been overheated he stopped the car and had it recovered. Having stripped the car down I found the worst thermostat bodge I have ever seen(see picture)25735. the v was full of expanding foam and the thermostat
had exploded also the inlet gasket had split. having spent a week cleaning it up I cannot find a reason for oil in the water ,I did a compression test and all pots were about the same,the plugs were dry. my question is could the head gasket have expired? ive put it all back together with new gaskets all round and new thermostat kit and it runs smoothly with no smoke or steam but im having a job cleaning out the cooling system but I how can i tell if there is any new oil going into the water? any assistance would be great thanks

[SD1too]

Hi Simon,

I was in this situation a few years back when I repaired a VW Golf with a failed ATF cooler. The expansion tank was full of 'strawberry yoghourt'. I am trying to remember now what I did. I'm fairly sure that I removed the expansion tank and washed it in a hot detergent solution to remove all the oil residue. If you have any Gunk use that first. I think I did this a couple of times and kept draining and refilling until the coolant was no longer contaminated.

I doubt very much that your KV6 head gaskets are responsible. The split inlet manifold gasket is more likely I'd have thought.

Simon

[kaiser]

Hi all, I have just bought a 2003 mgzt 180 auto in le mans green, I bought it as a non runner . the previous owner says it had been overheated he stopped the car and had it recovered. Having stripped the car down I found the worst thermostat bodge I have ever seen(see picture)25735. the v was full of expanding foam and the thermostat
had exploded also the inlet gasket had split. having spent a week cleaning it up I cannot find a reason for oil in the water ,I did a compression test and all pots were about the same,the plugs were dry. my question is could the head gasket have expired? ive put it all back together with new gaskets all round and new thermostat kit and it runs smoothly with no smoke or steam but im having a job cleaning out the cooling system but I how can i tell if there is any new oil going into the water? any assistance would be great thanks

Water in the oil can come from basically 4 places.
1. Head gasket
2. Inlet manifolds
3. Leaks around the liners
4. A crack into the water chamber.
5. And for good measure the oil cooler.

Normally these engines are not prone to head gasket failures. The inlet manifolds are more likely, usually there would be associated hesitation when cold and even water lock, if severe.
Leaks around the liners will usually result in water in the oil, mayonnaise under the oil filler cap even with a hot engine, and if bad, water in the oil.
A crack can happen in the block.
The oil cooler can be by-passed, and is only present on the automatic V6, afaik.

I would replace the inlet manifold gaskets and the thermostat as a first option. Run the engine and see.

It is almost impossible to give better advice until you have some experience with a running engine.

But whatever you do, check water often. These engines are cumbersome to fill, as trapped air is often present if not careful. Don't rely on the temp gauge, they are painted on the dash, or might as well have been.:D

[simon74]

HI thanks for the quick replies, I can confirm there is no water in the oil or water in the bores, I am hoping it was just the inlet manifold gaskets, I have all new gaskets from rimmers,im just waiting on a genuine mg thermostat housing as the pattern one I had was rubbish...and wouldn't seal , the car on the outside is immaculate but the engine looks like it has not been serviced in 40,000 miles except for the thermostat bodge.
will rebuild it next week when the parts arrive and let you all know how I get on.thanks

[kaiser]

Many Rover engines have been neglected. they usually are black and sooted up inside.
I think the service interval is far too long as a standard.

I would get a good Diesel engine oil and use that with a new filter. These oils have a lot of detergents to loosen carbon and sludge in the dirty Diesel engines, that should help your engine too.

Also be aware of the belts on these engines. They are not prone to giving trouble, but should be replaced at 90000 miles or 6 years according to Rover. Many have lasted much longer, but if there has been problems with water leask etc, it might be worth having a look. Check also the water pump, they are prone to leaking and will leak near the belts. Don't forget to renew anything in there having a bearing, is usually good advice.

But first, as you say, have a look and see if the engine behaves. Look at the service book and check for belt change or if not available, check the belts physically.

Good luck!

[chris75]

The oil cooler can be by-passed, and is only present on the automatic V6, afaik.




I can confirm that my 2.0L v6 manual also has an oil cooler :}

[simon74]

well,i got the car back together,got it running and it drove ok but there is too much pressure in the header tank and there is fresh oil in the water so I am afraid its gonna have to be stripped back down and the head gaskets replaced.....wish me luck
:shrug::shrug:

[Ched]

Before you do that bypass the oil cooler, ask me how I know.:)

[SD1too]

Before you do that bypass the oil cooler, ask me how I know.:)
:wot:

And remember your own evidence Simon:
I did a compression test and all pots were about the same, the plugs were dry.
Don't rush into messing with the head gaskets on the KV6. I challenge you to find a single proven incidence of their failure through overheating on this, or any other, forum. :)

Simon

[simon74]

HI
well I thought about the oil cooler but, it just seemed there was too much pressure in the header tank , when its ticking over when warm(not hot)with the cap off it just spews the water out,if you rev it seems to just spray more and more out. Kaiser mentioned on one of his posts about filling the cooling system with the engine running but as it is there is no way I could do this.
I will try bypassing the oil cooler and see what it does, on another note I cant get the heater to bleed but I wonder if this is full of oil too.will let you know the result and thanks for your advise!!!:}

[SD1too]

... when its ticking over when warm(not hot)with the cap off it just spews the water out ...
That's normal; you should always have the expansion tank cap fitted once the engine has warmed and the coolant starts to expand.

Have you followed MGR's procedure for refilling the KV6? Firstly, the expansion tank needs to be raised during the filling and bleeding process. It is then refitted before the engine is started, run at a very fast idle and coolant added until the level begins to rise. Then you fit the cap! For full details, search the forum under my user name, ensuring that you find the KV6 posting (the other engines are slightly different).
I cant get the heater to bleed ...
You can't bleed the heater separately. There is only one bleed screw, and that's in the bottom radiator hose beside the throttle body. If you suspect that the heater matrix is blocked by emulsified oil, I'm afraid you'll have to remove it to clean it out on the bench.

Simon

[kaiser]

HI
well I thought about the oil cooler but, it just seemed there was too much pressure in the header tank , when its ticking over when warm(not hot)with the cap off it just spews the water out,if you rev it seems to just spray more and more out. Kaiser mentioned on one of his posts about filling the cooling system with the engine running but as it is there is no way I could do this.
I will try bypassing the oil cooler and see what it does, on another note I cant get the heater to bleed but I wonder if this is full of oil too.will let you know the result and thanks for your advise!!!:}

The method of filling the engine requires that the revs are kept high. The engine will always spew water out if close to full, when the revs drop if not capped. About 2500 is about right. I normally fill the system then invert a full 2 liter coke bottle in the header tank, and leave it there while I rev the engine. Then you can see what is going on.
Once the bottle does not empty anymore, I take it away and close the cap, while keeping the revs.

Works fine, but let it cool and then top up as (if) required.

The revs forces water through the heater, even if the thermostat is stuck and minimizes any air there.

The filling while keeping the revs high was originally suggested by Rover for the V8 engine, which also tended to trap air in the penthouse inlet manifold. But of course that was in an age where people on average knew more about their cars than seems to be the case today.
I suspect today you would have to write two pages about the dangers of hot water, the harmful side effects of anti freeze, safety regulations regarding protective clothing, glasses and gloves not to mention a helmet and shoes.:getmecoat:

The pressurization you see is most likely normal and not excessive as from HGF.

And the heater element can be flushed in situ. Just find the two hoses going in/out of the bulkhead behind the engine, and separate them at the most convenient places, now the hoses are attached to the heater only, and you can force water through in both directions. Get a white plastic bucket, and make sure the water that comes out goes in there first. That will give you a visual on what comes out in terms of sediment. And yes, there could will be quite a bit.

[SD1too]

The method of filling the engine requires that the revs are kept high. About 2500 is about right.
Simon74; you may like to know that MG Rover specifies between 1,500 and 2,500 rpm. I have always stayed at the lower end of that range and never had any problems.

Simon

[Simon.h]

All KV6 have a engine oil cooler which uses engine coolant!
Ask Ched as he has had a leaking one!

[simon74]

HI all just a quick update, I took the water pipes off the oil cooler and found the water pipes completely full of oil25984
I bypassed the oil cooler with a piece of copper pipe and ran the car.
the car bled the air straight away and the heater became warm.
also I noticed the open water unions from the oil cooler were dripping oil so I can assume this is the culprit, so I have ordered a second hand one from fleabay and will fit as soon as it arrives.
Many thanks for everyones help and knowledge

[SD1too]

... there is fresh oil in the water so I am afraid its gonna have ... the head gaskets replaced.....
Lucky that you didn't go ahead with that idea, eh Simon! :D
I really must start counting.

Simon

[Simon.h]

Lucky that you didn't go ahead with that idea, eh Simon! :D
I really must start counting.

Simon

I think you should Simon!

Is it me or is oil cooler faults on the increase? Just think how many times a KV6 engine with this fault is put down as HGF as we all heard the saying 'its a Rover so it's your HG mate'

[Canonite]

ive read this thread with interest and while troublesome for the OP it has provided some helpful knowledge.

[AURORA MG]

This forum is a 1st Class dats base of knowledge & knowhows!! Just a shame that there are not more people that think of looking here before they keep breaking up the cars & advertising bits on fleabay! :mad:

[simon74]

This forum is one of the best places for Knowledge,i could have quite easily caused myself loads of work thinking it was H.G.F,all I can say is thanks everyone!!!!!:):):)

[SD1too]

This forum is one of the best places for Knowledge,i could have quite easily caused myself loads of work thinking it was H.G.F,all I can say is thanks everyone!!!!!:):):)
Of course we always welcome satisfied customers as full club members. The annual subscription is less than the cost of two gallons of petrol! ;)

Simon

[Ched]

Check your replacement carefully, after fitting mine it leaked, this time water and only when it reached operating temp.
Its replacement is fine.
Oh and if you can get one with he pipes already fitted even better, I couldn't shift mine at all,and I used a lambda socket to undo the pipes from the engine, so easy.

[simon74]

Hi all,
I have become a full member!, as you say I think its worth it to keep a great site like this going..
Ched thanks for this, I bought one with the pipes attached as I thought the pipes on the cooler might be a pig to undo. whats the access like attaching the pipes,i know you said you used a lambda socket but I don't own one of them yet!!will I be able to get in there with a spanner

[Ched]

I did try with a spanner but there is not enough room, it really is easy with the lambda socket, put it on full right lock and remove the o's front wheel and you have a bit more room to work, I also jacked the front of the car so that the wheels were just clear of the floor.

[simon74]

Hi all
just a quick update, the car is back together and back on the road...:}the car is not losing any fluids,and seems to drive quite nice but maybe a little bit sluggish, the idle is even and correct, only thing I have found is the heater only gets hot when the car is driven quite hard and the cooling fan kicks in after a short journey,the car doesn't seem to be overheating(I know the gauges on these aren't accurate)but the engine doesn't even feel that hot so im hoping an airlock?, I followed the advice on filling the system but is there anyway to get the air out once and for all when I do a coolant change again..


thanks all

[capese21]

is there anyway to get the air out once and for all when I do a coolant change again..

There is a way, Vacuum fill it. Make a system from a pela pump. There is a thread on it somewhere...........I will have a look.

found it!!

http://www.the75andztclub.co.uk/forum/showthread.php?t=41864

[kaiser]

It sounds as if you still have air in the system, or you are loosing water.
Check (and top up) whenever the car is cold.

If the heater only works when the car is at high revs, it is usually a sign that water is low.

The sluggishness could be either a slack accelerator cable, the VIS system not operating properly, wrong cam timing or a blocked exhaust.

Check that the accelerator does not bottom out on the carpet prematurely.

[SD1too]

... the car doesn't seem to be overheating (I know the gauges on these aren't accurate) ..
Activate the instrument pack diagnostics for a digital display of the actual coolant temperature (see "How to ..." section). Make sure that the radiator cooling fan starts running at 100°C.
I followed the advice on filling the system ...
Did you raise the expansion tank during the initial filling? I've found with my KV6 that the expansion tank needs topping up about three or four times once cool after a journey, then it's fine. Check your coolant level today to see if it's at 'max'.

Although filling using a vacuum pump is an alternative method described by MG Rover (mainly for dealers who possess one I imagine), it's not necessary simply to remove air. Following the standard instructions works perfectly well.

Simon

[kaiser]

There is no need to go through a complete drainage and re-fill. To get the air out of the system is just a bit involved if you want it done in one go.
Since you are up and running, so to speak:), it is simply a matter of now checking and adding water/antifreeze, and keeping an eye on the level.

If you continuously have water below the line, between top ups, you are continuously losing water, and you have a leak.
If not, the level will stabilize with the top ups and the system will be full.

But even after that, keep an eye on it regularly.

And just to add, if you overfill, no harm is done, but it will then spit out the excess water and find a natural level, somewhere between the MIN and MAX marks. Continuing to overfill out of ignorance will lead you to thinking the car looses water, as long as the level is between the marks, you are fine. Squeeze the big rubber pipe when checking, and you will see the level in the expansion box rise and fall with the squeezes.

[simon74]

Hi all

I have checked the water level when cool today and its fine. the reason why I want to drain the cooling system again is that there is still a lot of oily gunk(no new oil)but remnents of the oil cooler splitting,i am assuming there is still some of this sludge in the heater matrix .I am quite confident there is no mixing of the fluids so it must be down to an airlock

[simon74]

Hi all
after putting a couple of hundred miles on the car ive come across the following problems
1.No matter what I do, i cant get it to bleed properly, even though I followed all advice on here.
2. the heater is still cold until the car is under load and it gets warm but as soon as it drops to idle the heat fades away?? water level at cold is fine but there seems too much pressure in the system.
3. the cooling fan runs continually even after a short 5 minute drive even though it doesn't seem to be overheating
4.while trying to bleed the car using the bottle method there seems to be more oil in the water.
5 also might not be connected but the car seems sluggish and uses a lot of fuel.
I know this has been discussed before but a mechanic friend said it sounds like the front cylinder head gasket has been cooked.

Not sure what to do im a competent amateur mechanic but im tempted to take it off the road(now that my 1.8t is fixed) and strip the ****** down. but any advice would be great

[kaiser]

The V6 can feel sluggish compared to the turbo.
I suggest you monitor the temperature of the cooling system using the instrument pack. Then you will know if the engine is getting hot.

If there still is air in the system, after several attempts to bleed, it is because you are loosing water. Then you must find the leak. No bleeding is ever going to sort that out.

There are a couple of places where water loss it is most likely. Thermostat, inlet manifold, water pump, rusty steel pipes below radiator in front, expansion box cap.

[simon74]

Hi
there is no leaks I can find
thermostat and pipework replaced
both inlets fitted with new gaskets
new water pump
all pipework checked and no water loss.
I am going to try the temp with the dash at the weekend and do a compression test.
this is the 3rd v6 ive owned and this one just seems to be lacking any go ,I understand the vis motors can be to blame but I keep going back to the suspected h/g

[kaiser]

I doubt that a compression test is going to tell you much. I would rather connect some compressed air into an old spark plug for each cylinder in turn, to see if there is air going into the water.

Sluggishness can also arise from a wrongly timed camshaft, or two, or three or-- well, you get it.

If you remove the rear cam covers, you can check the position of the rear sprockets. They are supposed to be in line when the engine is in safe mode.

The last place where you could loose water and get oil in the water is in the oil cooler. That might be worth a try. You can by-pass it with a piece of piping.

[simon74]

Hi

I replaced the oil cooler, and yes I could I bypass it but would it damage the engine with it not been connected to the water system?

[kaiser]

I think the oil cooler is necessary if the engine is pressed hard. But I am certain you could by-pass the unit without ill effect, provided you don't overdo things.

I would not hesitate for a moment to by-pass it, just to get an idea of it's complicity in what you see.

But, if it has been replaced, did you test it before you fitted it?

[SD1too]

No matter what I do, i cant get it to bleed properly ...
What do you mean exactly? Are you saying that you never get a steady stream of coolant from the bleed screw? Can you confirm that you have raised the expansion tank during the process?
the heater is still cold until the car is under load and it gets warm but as soon as it drops to idle the heat fades away?
Hmmm. Have you renewed the expansion tank cap? Those symptoms sound like lack of pressurisation.
... the cooling fan runs continually even after a short 5 minute drive even though it doesn't seem to be overheating ...
What do ytou mean by "doesn't seem to be overheating". Is it or isn't it? Have you monitored the actual coolant temperature using the IPK diagnostics as I advised in my last post?
... also might not be connected but the car seems sluggish and uses a lot of fuel.
Concentrate on the cooling system. Don't introduce any more "seems"! :D We'll look at those issues later.
... a mechanic friend said it sounds like the front cylinder head gasket has been cooked.
Hmmm. The KV6 cylinder head gaskets don't give trouble. Ask him why he's chosen the "front" bank (tell him it's actually known as the left-hand bank). ;)


I am going to try the temp with the dash at the weekend ..
Good! I agree with Kaiser that a compression test is not appropriate for your fault symptoms.

I replaced the oil cooler...
New or second hand? Did you thoroughly flush the cooling system afterwards and change the oil?
... and yes I could I bypass it but would it damage the engine with it not been connected to the water system?
Not as a temporary measure, no, and provided that you don't drive like Fangio. Ask club member Ched; he's done it.

Give us some answers to our questions please Simon.

Simon

[simon74]

Right to answer some of your questions :
yes the expansion cap was replaced as the original was split
The coolant was bled as per instructions and coolant did flow
Through the bleed screw.
I also tried the way with the clear bottle on the expansion tank
While fitting (this is where the oil residue can be seen.
My friend said the h/g on front bank(or left bank if you like)
Would most likely have failed as that was the one where the inlet
Gasket had split and the temperatures on that bank would have been
Higher than the other.
The oil cooler was bought as a quality tested unit
And the cooling system had been flushed 4 or 5 times
And it looks like there is fresh oil in the water

I m intrigued that there is not many h/g failures on the kv6
To me all this points to h/g failure but will try the
Ipk and bypass the oil cooler.

Thanks

[kaiser]

I think it would be good if there was a picture of the oil you see. It might not be exactly what you think it is.

In any case the head gaskets on the V6 are usually not problematic.

[SD1too]

Simon,

First of all thank you for your answers. Here's what you said a few weeks ago:
water unions from the oil cooler were dripping oil so I can assume this is the culprit, so I have ordered a second hand one from fleabay ...
Let's not beat around the bush, if you still have traces of oil in the coolant then it's either a residue from the original faulty cooler (it's difficult to get it all out) or you have to suspect your second-hand replacement.

Remember that last time you proved beyond doubt that the oil cooler was responsible:
I took the water pipes off the oil cooler and found the water pipes completely full of oil ... I bypassed the oil cooler ... the car bled the air straight away and the heater became warm.

So there is no evidence of head gasket failure. I don't agree with your friend's idea. A failed inlet manifold gasket would not cause a head gasket to fail. On the forum we have had this before with the V6. Owners seem keen to believe that they have a horrendous failure on their hands. It's always turned out to be something else, and often quite simple.

The oil cooler was bought as a quality tested unit ..
I very much doubt that this is true for a second-hand component from e-bay. That description applies to remanufactured parts from reputable companies. Simon; I strongly recommend that you do the job properly and once only: buy a new oil cooler in a manufacturer's box from X-Part or a reliable motor factor with premises such as Euro Car Parts. You're not saving any money in the long term by messing about with e-bay.

Simon