HGF how can I tell for sure?

[frostybox]

Hi

I have a '99 MGF with a VVC engine that was fitted in '01. It's been stood for a long time and now I'm ready to get it back on the road but I suspect HGF. However the only symptom is a very small amount of 'mayo' on the dipstick, very small and I loose steam through my expansion bottle. The expansion cap seems fine with no signs of coolant spillage and there is no oil mix in the bottle either. Both engine fans work fine and there is no coolant leaks under any part of the car. Could the steam be an air lock in the system somewhere? How can I be sure if it is HGF? Can I safely bleed the system and replace the coolant as I'm skeptical of running the engine in case of HGF?
What coolant would you recommend if it is safe to go ahead and replace?

Any advice appreciated.

Thanks

Jo

[SWMG Admin]

Hi Jo, sent you reply to your pm and see you have posted this ;D

Could well be condensation, and very possibly faulty exp cap,they fail frequently even new ones so for sake of a fiver get another and replace it. you should perhaps get it pressure tested,pop down to Mark in Barry at BMS perhps and have it all checked out by qualified Rover MG techie, Dave

[frostybox]

Hi Dave

Replied to your PM, thanks very much. Here's some pics of the offending issue. Hopefully someone can relate as I'll struggle to get the car to Mark as I can't risk driving it as it is. I'll speak to the other you mentioned and hopefully he can take a look with the car in situ and we can go from there.

Many thanks again

Jo

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[frostybox]

Another

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[frostybox]

Cap

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[frostybox]

Another Dip!!

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[SWMG Admin]

My guess is it's still a condensation blob especially as you've not used car for long time,i had exact same symptoms as you once with my F and the blob of mayo on botom of dipstick my F used to stand unused for long periods of time well few weeks at a time as not main car anyway,i'm not suggesting you should do same as me but i gave my F a good hard blast down road for half hour or so and the blob dissapeared,if you should go for blast replace exp cap first though

[frostybox]

That pretty much settles it for me, I'll fill up will coolant and blast the bugger down the M4 dust away the cobwebs ;D what's the worst that can happen - eek don't say it

Look out South wales

Jo x

[frostybox]

Just an after thought, what if it's an airlock? Is it safe to blast it down the M4?

Ta

Jo

[SWMG Admin]

You say you lose steam from exp bottle, whereabouts? does it look like from the cap? also worth a check is the small coolant hose at base of exp bottle, mine was leaking a bit there i took it off cleaned up and replaced and that was that,it's process of elimination really,keep your eye on the temp guage even though they are sort of cr@p but if you see it going way way high,slow down turn your heater on full and full blow to help cool down,where's Jerry,Mike and Pete when you need them,what do i know ha ha

[Jerry & Di]

Ermm - difficult to say over the interwebby, but I'd get a proper new header tank cap (Rimmers etc), check oil and coolant levels etc and see what happens. Run it around a bit. Coolant caps are notoriously "dubious" and can only be tested with special kit.

Steam?? - should be no steam, or do you mean condensation out of the exhaust?

I wouldn't bother changing any coolant after after you are certain that all is well. Bleeding from the three points is always useful if in doubt. I find it easier if the rear of the car is higher than the front.

[frostybox]

Hi Dave, Jerry & Di

The 'steam' is obvious overheating coming from the cap as everywhere else is seemless and tight, no leaks or air gaps. Temp gauges on both temperature and oil seem hit and miss. Temp gauge goes from nothing to steaming to mid way then immediately nothing. The oil gauge has never worked, I think anyway. I've never noticed any fluctuation in the gauge so decided it was faulty so replaced it, only for the 'new one' to register nothing also! just something else to add to the shyte list. I'll get there, just does my head it one thing after another!

thanks for your help guys, I'm really trying to do this and learn from this on my own. All advice and Patience really and truelly appreciated

Cheers

Jo

[Jerry & Di]

The oil gauge is irrelevant - very few cars have had one, it's only for marketing reasons to make it look "old fashioned" and "sporty"

The steam out of the cap is vital to eliminate - replace it.

The temperature gauge going up and down could well be an air lock - the heater valve must be wide open when bleeding.

If you can fix those two things, drive it and see how the oil consistancy develops - or not

[g4wam]

hello there,
on the basis that the steam thing happened to me -check the centre brass valve in the header tank cap -if it is off centre it is blown .
regards
Mike

[Jerry & Di]

Oct 31, 2011 14:41:15 GMT g4wam said:

hello there,
on the basis that the steam thing happened to me -check the centre brass valve in the header tank cap -if it is off centre it is blown .
regards
Mike

That's a fallacy

I took one apart years ago carefully and examined the bits. The reason it was off centre was immaterial to the sealing action, but proved that it had lifted under pressure, and resealed. I still have the bits

I have a rig at home that tests header tank caps, and good caps with off centre brass rivets seal just as well. In fact several new caps with central brass rivets fail to re-seat after lifting, and were rubbish

Finding a good new cap might be easier if you get one from a good supplier, rather than old stock which might have been made with worn press dies.