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MG MGF Technical - In need of some advice - white smoke and smell

Hey guys, first-time poster here.

So, I bought my '98 MGF 1.8 VVC about two months ago now. Beautiful car, love it to bits. It has a good service history and according to that, it had the head gasket done with the upgraded one less than 4k miles ago.

Now, to the problem. Recently, I was just coming off the motorway after a two hour drive, and after pulling up to some lights and stopping for a minute or so before they turned green, I noticed a pretty strong smell and misty-looking smoke seeping through the engine cover inside the car. It went away about 30 seconds after I started moving again, but then started smoking pretty profusely from the vents at the back (white smoke).

I was only down the road from my house, so I pulled up and switched the engine off. I opened the boot and, sure enough, smoke was pouring out and the coolant was bubbling. I left it to cool down overnight and in the morning found that the coolant had all gone. I filled it up again I left it running for 10 minutes or so, and it had no problems.

However, nowadays I still smell that same scent sometimes after I've been revving quite high and I pull up at lights and idle for a while. Again, it goes away once I start moving again, but it really is a strong smell and I worry that I'm not doing it any good by driving it.

Since then, all I've done is an oil flush, and i haven't seen it smoke yet but the smell still enters the cabin under the circumstances i mentioned last paragraph.

I really don't want it to be HGF, and it seems unlikely that it is, seeing as the gasket was done less than 4k miles ago.any suggestions? Has this happened to anyone else?

Sorry for the long post, but I really haven't been able to find anyone with these same symptoms so far on the net.

Anyway, best wishes - thanks for reading. Regards,
Matt.
M.W. Barker

Smoke or steam? If the former, I haven't a clue. But if the latter, then this could be a blown radiator fuse or non- or poorly functioning radiator or fan - both quite common. The moving air flow through the rad being enough to keep it cool enough under normal circs without the fan, but slower waterpump and lack of airflow at tickover, being enough to cause a recoverable overheat.
If your expansion bottle has been emptied, you may need to rebleed the system - airlocks can accentuate similar symptoms.
If you are new to the F, these sites give you searchable archives and all you ever need for maintaining it in good condition:-
http://www.mgfcar.de/index.htm
http://www.apttony.co.uk/
http://mgf.ultimatemg.com/
http://www.mgf-tf-central.co.uk/
If you don't care to wave the spanners yourself, I would take it to an MG savvy garage as overheating can lead to much worse if left......
Charless

Thanks for the reply, I'm fairly certain it's smoke as it is clearly visible when it occurs. I wish I could describe the smell as I'm sure that would give a relatively clear indication of what the problem is. Is it worth checking the rad anyway?

Also, not sure how relevant it is but I fitted an induction kit and the cold air intake is currently pretty poor. Was wondering if the air being sucked into the engine was too hot and possibly contaminated with other stuff from the engine bay. I've been told it probably makes no different except slightly worse performance. Got some tubing ordered so I'll have that sorted soon anyway.

Thanks again, happy sunday : )
M.W. Barker

Where coolant is disappearing, best to regard any visible vapour as steam until proven otherwise. If it was smoke from something mineral-based i.e. oil, I don't think you'd be in any doubt about how to describe the smell. If the induction is pulling in warm or hot air, the only effect that would have is to reduce power slightly.

As Charles suggests, inspection of all the coolant circuit components is very likely to reveal the source. I'd start by removing the engine access panel under the parcel shelf and running the engine up to temperature, and watch for steam coming from hose connections, particularly around the cylinder head - the chances of an elderly hose not having re-sealed fully after the gasket was changed are high. Whilst you're at it, bleed the system - even the slightest pocket of air in the system can have a dramatic effect.

New owners of the F/TF sometimes assume that because the dashboard temperature gauge didn't climb as far as the red sector the engine hasn't overheated. Sadly the gauge is not a reliable indicator of this, even the slightest rise above the 'normal' position of the needle means steam is going around the cooling system, i.e. overheat is in full swing.
bandit

Replace the Coolant Bottle cap with a new one. it sounds as if system is not pressurised and you could be loosing coolant through the faulty cap.
Julian S Foulger

Does it smell like curry?

If so, it's overheating coolant.
Sam Murray

Cheers for the input guys. Gonna have a fiddle and see what I can find. Curry? Haha, I don't think so. Its a hard smell to describe, but it can get pretty strong at times.
M.W. Barker

Certainly, the orange OAT coolant has a scented smell, wether one would think its curry, i guess depends on ones preference..Occasionally ive spilt some OAT while topping up the header tank, and when those spills evaporate on anything warm enough to enable that.. is has a scented smell.. not sickly sweet but certainly like a poor quality aftershave..:) ive never seen steam or smoke, but definitely the smell of evapaorating OAT is distinctive.. and given that anything acidic is likely to smell sweet.. ( Organic Acid Technology) then a sweet smell in anything that is coming out of the engine in any way.. is likely to include coolant, and if one considers that.. then looking at this.. should tell you why. http://en.wikipedia.org/wiki/Ethylene_glycol
N.J. Simon

Quite a number of years back in my old MGF I was travelling down the motorway when there was a large bang from behind me.

In looking in the mirror, I could see smoke, white smoke and I wasn't sure what had happened.

I was convinced it was on fire, due to the smoke and pulled over to the hard shoulder, got out and loads of smoke coming from the grill in the boot.

The coolant pipe (it a complex pipe with multiple joins) and one of the joints had given way .

I didn't know that at the time, and had the car towed home.

Once home I was able to open the engine bay, by unscrewing the panel and could clearly see pipe had gone.

Replaced pipe, refilled coolant and bled system. Car when on for years and traded in against TF.

So smoke could be steam

Brian
b buick

This thread was discussed between 04/03/2012 and 08/03/2012

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