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MG MGF Technical - mayo in expansion tank no water in oil
|My MGF 97 vvc has what appears to be oil in the expansion tank, sticky as well over the top inside of the tank and over the expansion cap itself. Now I hear you say Head G failure, now the tricky bit... no coolant loss, no water in oil no performance issues and no increase in engine temperature and a pressure check shows nothing.|
So what is it? Trying to determine what happened lately.. I had my Radiator replaced some 2000miles ago and the coolant was "replaced" - possibly not all of it checking a couple of times since I have topped it up this weekend and hence noticed the issue. Prior to me replacing the Rad, i tried putting in "No leaks" you know the brown stuff that fixes leaks, now this was a few thousand miles before I replaced the rad since i was hoping that the minor leak could be fixed, eventually the rad gave in.
Now, the stickyness to the top inside of the expansion tank could be elements of the "no leaks" however I wouldn't think it would be sticky?
So guys do have have a bizzare HGF or is something else going on?
What colour is the goo?
|Cream colour, also the cap above the engine itself is as clean as you like, car behaves fine with no smoke out of the exhaust. I have resently used STP fuel additive to clean the valves and engine.|
the residue is around the top of the expansion cap and in the fluid as well (surface) not sure how deep it goes. When I opened up the expansion cap the pressure was there as you would expect.
I have had the car for 3 years and as far as I know the HG has not been replaced.
|It could be HGF between water and high pressure oil (usual is water and low pressure oil, so the contamination is the other way).|
>Prior to me replacing the Rad, i tried putting in "No leaks"
Euch, I'd never use this stuff*, but I don't know if it would cause HGF.
Is the coolant the same stuff as before (you havn't switched to OAT coolant or from OAT coolant?)
|Sorry but I say you have a HGF.|
Identical to what I experienced. Do not use the car. You have probably caught it early enough not to have resulted in too much damage.
Get the car towed. Who replaced the radiator?
|I was thinking though regarding the coolant comment, Since the Rad was replaced they would have stuck new coolant in which possibly mixed with my old stuff. The new stuff is green - the old blue, I have been topping it up with Blue. Unfortunately the garage that replaced my rad have shut, they were a good and honest garage (rare) - possibly to honest hense they are shut now!|
would mixing coolant cause such a reaction ?
|If you mix OAT and non OAT then yes.|
Blue? I don'r remember the F ever using blue, IIRC it's just Green/yellow (non OAT) and Pink (OAT). Halfords sell Blue, but I don't know if it's OAT (says good for three years (OAT) VS good for two (nonOAT))
|I still think a CO2 test in the expansion tank would be a good idea to further assess the potential of a HGF.|
|The HC (not CO2!) test only tells you if you have a leak from the combustion to the water - remember:|
HG keeps apart:
1 Water (medium pressure)
2 Outside (very low pressure)
3 Oil (high pressure)
4 Oil (low pressure)
5 Combustion (pressure cycleing)
1&2 = wet alternator
1&3 = mayo in water
1&4 = mayo in oil
1&5 = HC in water, apparent boiling over
2&3 = oil leak
2&4 = oil smear, dirty engine
2&5 = noisy, unusual
3&4 = invisible, non terminal
3&5 = blue smoke (very unusual)
4&5 = nothing
So a HGF can be one or more of these things (usually 1&2 leads to lack of coolant, leads to cooking of rubber in HG, leads to multiple failure). and just cause you have one and not the others does not mean you don't have HGF.
gunge in the water will lead to HGF as the engine cannot cool itself properly.
|The gundge causing the engine not to cool itself properly is my main fear which will kick of a HGF regardless even if that is not the main cause. So what we are suggesting here is to remove my coolant totally, replace it with the defined correct stuff and start again. How am I going to get this crap out of the expansion / pipes then?|
Are there any sniffer tests worth doing?
Thing is you know the score, garages want to make money if I take it in and ask they will all say ... ah the Kseries engine, HGF mate hmmm with VAT that will be......
I wonder how many HGF are infact that as opposed to people like me mixing my fluids!
>I wonder how many HGF are infact that as opposed to people like me mixing my fluids!
very few I think, but be sure it was mixing fluids.
I don't know what this stuff is, but I would start by flushing the entire system with water (see Rob's site for details)
Take your time, do it twice alowing the system to get hot to the point of the fan comming on, and allow to cool for 20 mins before draining, and a further hour before filling again (don't want to wreck your engine with thermal shock!) then add the two part radiator flush, follow instructions about filling and draining (first part is evil, second part kills evilness). Then drain and flush with water like before twice again, then refill with 50 water/50 Superplus antifreeze from MGR (buy in five litre can)
|I'm off to an MG owners recommended garage in Bristol to take a quick look at lunchtime, will probably get him to flush it and refill that way I know its done right.|
Will let you know.
Right, '97 cars were before OAT anti-freeze, so it's very unlikely that Nigel's car has had OAT as a replacement, as few people are aware of it and it is more expensive. The original coolant colour (in '97) was yellow/green, SuperPlus 3. For a short time, vins 512772 to 520012, the coolant was blue, Unipart AFC. Later cars have OAT coolant, orange/pink. As an aside, although it is not advisable to top up OAT cars with non-OAT ant-freeze, it can be done in extremis without the engine expiring or creating mayo of any colour. I would stick to the yellow/green SuperPlus 3.
As the mayo is cream I don't think it's a result of the rad bunging-up stuff, which is brown. Although it's too late, I wouldn't use this in the damp-linered K engine, as the coolant jacket around the liners is just 0.65 mm wide (or narrow). In fact I wouldn't use it at all. Who knows whether it has tried to bridge this gap. I'm not too keen on the STP stuff either, but then I am old school.
Follow Will's advice and Rob's instructions and flush the system to try to get all the crap out. Refill using SuperPlus 3. Remember you need to open both pipes under the car to drain the coolant.
Good luck, Kes.
|>>>>>Blue? I don'r remember the F ever using blue,|
Mine came with the blue stuff and it is only available in 25 ltr drums. A right pain in the neck when you have to goto the dealer service bay for it.
Changing to red/pink this week/next
|As Stephen says, the stuff you get from the dealerships these days IS blue!!! AND it is OAT 8oO|
Discovered this only very recently. Until getting my car serviced at Techspeed, the coolant was green, non-OAT. Since then, Techspeed have serviced the car regularly, and have changed the coolant type - now blue.
Following the recent coolant loose thanks to leaking coolant hoses, I needed to top up the coolant. I had some Unipart Superplus 3 - but this was green - and urm, the coolant in the car was blue. So I checked- and the blue stuff in the car is OAT based coolant. The stuff you buy from Rover these days is blue OAT based coolant (I borrowed some from Dave, who had to buy 5-litres of the stuff and had plenty spare).
So the situation is:
If your coolant is GREEN, you have the old Superplus 3 antifreeze in your car.
If your coolant is BLUE, and a Rover dealer or Techspeed etc put it in, then it is OAT based.
Blue coolants from other sources I can't comment on - you'd have to check the label on the bottle.
If your coolant is ORANGE, then you have OAT based coolant.
NEVER mix OAT coolant with non-OAT.
This might be the case here Nigel, so it may be worth getting your cooling system drained, flushed and re-filled exactly as Will and Kes have suggested.
Not sure whether mixing OAT and non-OAT coolant would result in a mayo-like precipitate though? No sure I want to find out - but since I have a little bit of both types of coolant, I don't mind doing a little "chemistry experiment" to find out if you're interested!
|Get mixing, however I think it will need to be warmed up as well. Probably need to get your chemistry set out.|
I am off to this garage in the next hour - bets on they say HGF!
|Okay - might be a bit of fun this evening. Not sure how I am going to explain to my SO why I am boiling a mix of coolant on her beloved Smeg hob... ;o)|
|<<The HC (not CO2!)>>|
A standard test for HGF is monitoring for an excess of CO2 in the expansion tank or radiator. I agree it will not identify all HGFs but it's still often carried out as a precaution.
Good luck Nigel.
|The MG garage said it was possibly a HGF, although he wasn't too sure his view was since they are so unreliable it probably is he quoted me £480 inc VAT for HG and Skimming, he advised the skimming "to be sure". I did notice that the cream had disappeared under heat and pressure after a decent drive, the solution in the tank is far more fluid but on the surface are like collection of small balls of brown and while burning my finger in the solution appear to be greesy to the touch then slighty sticky. During the hour journey the car did not over heat once and the engine temp along with the water temp didn't go above normal, the car drove fine no misfires issues, smoke or nothing even outpaced a cocky MX5 off the start.|
|Nigel, thought you'd like to know the results of the 'chemistry' experiment ;o)|
1. to determine whether mixing 'green' and 'blue' coolant would result in precipitation
2. to determine whether mixing the coolants would alter the boiling point
Methods & materials:
25ml Superplus 3 antifreeze - call it 'A'
25ml Blue OAT-based coolant - call it 'B'
London tap water ;o)
Dilute 'A' and 'B' 50:50 v/v with water. Call it 'C'.
Coolant mixes heated in 100ml pyrex beaker with blow torch (thought I'd better not use the Smeg hob LOL ;o)). When boiling, measure temperature with a mercury thermometer.
'A' actually appears yellow, with a green tinge, especially to its miniscus. Good clarity and transparant, albeit with yellow colouration.
'B' was blue. Good clarity and transparant.
When 'A' and 'B' were mixed, 50:50, the result was,unsurprisingly, a bilious green concoction - probably unlike a student's DIY cocktail nasty... Translucent. Looked rather turbid. No precipitates.
'A' boiled at 103.5C at atmospheric pressure
'B' boiled at 104C at atmospheric pressure
'C' boiled at 103.5C at atmospheric pressure
Tap water boiled at 99C. D'oh. Probably reflects an imperfectly calibrated thermometer and the fact that I was attempting to boil water in a beaker in the garden!!!
apart from the lovely colour (not), nothing too nasty happened when mixing the coolants in respect to precipitation or boiling point. However, I do wonder if the turbid appearance of 'C' might be reflectant of a chemical reaction? Might be worth checking the pH's of each of the coolant mixes. An acidic coolant could corrode the aluminium head...
In essence, I don't think we can use this as an explanation for your 'mayo in the coolant' observation. Most likely an HGF, sorry. :o(
|did you try wisking it?|
|No, but I should have added vingear.|
|Posted the pix of the 'experiment' here: http://www.mgf.ultimatemg.com/coolant|
|Nigel, i've seen a fair few K series HGF in the past and the symptoms you have I came across on a 97 Rover 214 recently. Last December I had this 200 in for routine service and noticed that the coolant bottle had slight mayo effect in it and on the cap. I could'nt confirm CO in the coolant and so ruled out HGF. The car upto this point had FSH from decent garages and I was doing it for the fourth time. The car then came back to me in March with the symptom of slight coolant loss - it had dropped to just under the MIN from MAX. Still had slight mayo effect but no more than before. I then took the plunge and carried out a HG change, the car never overheated in any way and therefore skimming the head was'nt needed.|
Nearly 2 months on and the mayo has'nt returned and cooland level has not dropped (the 200 gets regularly driven between Essex and Liverpool so mileage is quite high).
Catch HGF before it goes big time, your head will need skimming and it's a damn awful job flushing out those coolant pipes and rad etc if oil contaminates fully.
|You are probably right just another form of HGF, I was praying for some other rope to cling onto but facts are facts really it must be oil in there somewhere.|
Yesterday I observed exactly the same symptoms you did, i.e. Mayo smears and lumps in the coolant header tank, clean uncontaminated oil and no hint of overheating but about one inch of coolant missing.
My Rover dealer has just confirmed that my '97 MPi 1.8 (62k miles) has head gasket failure and coolant pipe corrosion and quoted £450 for labour alone!
What's worse, I was booked on Highlander tomorrow!
This thread was discussed between 25/04/2004 and 30/04/2004
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