Hi,
can anyone help with a problem that has been baffling garages around here with my P reg MGF VVC?
I am by no means mechanically minded so forgive my potential incorrect use of terminology!
The problem first started a week ago when after driving at 70mph for 35 miles, I dropped down to 30mph. The temp gauge started to rise, got to just underhalf way then stopped. Here's the first problem, apparantly the normal level for the gauge is one bar under the halfway mark, yet mine normally sits one bar above the lowest bar! A couple of mninutes later steam started to come out of the coolant tank. My first thought was HGF, so I checked the oil, no milkyness. I called out the AA, they did their pressure and chemical tests and the car was fine. They towed me to a local garage who said it WAS HGF and the head had to be sent off for the tests - ie £££.
I was not convinced so I got the AA out again, they did the tests again, the car passed again and with them following me, I drove 35 miles to another garage I had been recommended. They diagniosed a leak in the pipe taking the coolant from the back to the radiator. This was apparantly causing a loss of coolant, hence the problems. They changed the pipe, problem solved!
But unfortunately it is not! The same thing has happaned twice again, I drive at speed, slow down, the temp gauge rises to just under half way, then steam comes out of the coolant tank!
It is as if whenever the car has been warmed up and isnt travelling at speed, itsl liable to heat up, however the temp gauge never gets above just under half way, so is it really the engine overheating, or there too much pressure in the 'system'? Does the coolant need bleeding?
This morning I arrived at work after doing a 70mph stretch (no problem), drop down to 30mph - gauge starts to rise, get sto just under halfway and stops at that level. I pulled up at work and I assume the fan kicked in as the gauge dropped. I had a look at the cooland tank and despite the cap being tighly screwed on, there was a slight hissing noise coming out of it.
On my journey home, I was driving mostly at speed and therefore the airflow I suspect keeps everything cool, I pulled up and left the engine running. Temp gauge went up to one below middle bar - which is not something to worry about I believe - and I left the car running idle for about 8-10 mins. The gauge never went above this level, but sure enough, despite new cap, after 8-10 mins the steam begin to rise out of the back of the car again!
I opened the boot and it sounded like there was a 'gurgling' noise coming from the left hand side of the engine (sorry cannot be more descriptive than that) and the coolant level in the tank started to rise to above its normal 'cold' level. It was bubbling away.
I have changed the coolant cap so it cannot be that.
Turning the heater on and off seems to make now difference.
Does anyone know what is going on!!!
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Fairly safe bet it's HGF on this pathetic engine.
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Could be the seals on the water heated inlet manifold.
They go first, then the HGF..
madf
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Fairly safe bet it's HGF on this pathetic engine.
>
Ditto Xileno
My brothers (factory built) Caterham with the MGF engine did it's first HG at 3 yrs old and 7000 miles.
Thats why you can pick second hand MGF's up for peanuts as most mechanics want nothing to do with them.
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SNIP comments removed - DD
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">SNIP comments removed - DD<"
I'll rephrase my comments. HGF probably occured due to lack of use. 7k in 3 years? Why bother owning it?
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>>HGF probably occured due to lack of use.
Nothing to do with it
7k in 3 years?
Why bother owning it?
whats that to do with you???
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Steve
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">Nothing to do with it<"
Leave an alloy engine unused and there is a risk of corrosion within the coolant system, leading to micro-boiling and subsequent HGF failure.
">whats that to do with you?<"
You posted it, I responded.
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">pathetic engine.<"
R500
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amkdl
These things are a nightmare and I'll run a mile before getting involved with one. Some of their innumerable cooling faults:-
The gauges don't read correctly. Get a laser thermometer so that you have true readings to work with.
The jiggle valve in the pipe to the expansion tank gets stuck and they airlock. They may need a vacuum bleeder to get all the air out anyway.
There was a tip about drilling a hole in the t/stat; you should use a lower [82] one anyway. Makes the heads last longer.
If they crack the head or the cylinder liners, it may only show up under load and very hot.
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>>There was a tip about drilling a hole in the t/stat;
They dont have a bypass,so worth doing
>>you should use a lower [82] one anyway. Makes the heads last longer.
Wont make any difference as far as I`ve seen so far
It does sound like an air lock,they do suffer this the K-series and sometimes very difficult to bleed
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Steve
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">These things are a nightmare<"
One the toughest engines on the race track.
">Get a laser thermometer so that you have true readings to work with.<"
No it won't, because laser thermometers don't measure coolant temperature.
"> They may need a vacuum bleeder to get all the air out anyway.<"
No, just needs someone to follow the correct process
">you should use a lower [82] one anyway. Makes the heads last longer.<"
Why? In fact, running at lower temps can lead to more problems. I've run a K-series in a kitcar with an electric coolant pump and no stat, coolant temp could be maintained at a steady 98', no overheating, no coolant spewing out of the expansion tank. The biggest design problem with the K-series is the location of the thermostat, coolant inlet rather than coolant exhaust. That's why the OP needs to see a specialist.
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I'm quickly coming to the conclusion that it's becoming a waste of time posting on this forum.
"One of the toughest engines on the track."
I was clearly describing the car - not the engine.
"Laser thermometers don't measure coolant temperature."
Who cares? I want to know roughly how hot whatever I point it at is; head surface, hose, rad, whatever... It's the temp differential that provides the clues.
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">waste of time posting on this forum.<"
Not at all.
"> not the engine.<"
It's the engine that's overheating.
">Who cares? <"
You clearly do. Laser thermometers have their uses, measuring coolant temp isn't one of them.
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Try new expansion cap 1st , then check inlet manifold gasket! (common) then if still problem HG. Have you had both water pipes replaced?
common cause of head gasket failures on these. When it comes to HG don't skimp on cost have it done properly and make sure bypass valve clear & have a head leak test.
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Visit a K-series specialist.
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Visit a K-series specialist.
Micky, that's a very fine sentiment; it's something that we should all try our best to do.
I'm sure that they would welcome someone to talk to.
< potentially offensive comment removed after complaint > PG
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deleted. PU
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Can we please bring this back on topic. It's starting to irritate me now,, the OP asked a reasonable question and in the tradition of this forum, in particular of Technical can we respect that please ?
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I concur, we must stop this needless criticism of the K-series
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As its had a pipe replaced its not been bled properly,once that has been done I suspect problem will go away!
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Steve
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As a regular to this site to view advice and poster of the occasional question I consider the advice screwloose gives excellent and very knowledgable. Others, however, seem to post their view based on little or no knowledge or experience of the particular discussion subject whatsoever!!!
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Screwloose has given excellent advice which should be followed. Some of the other comments are a bit odd-ball, to say the least.
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A lot of good information on this web site on bleeding MGF cooling systems ... Jiggle valve ... also mentions a 4th bleed location ... scroll half way down ...
www.lame-delegation.de/mgf-net.de/bleed/
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The best advice so far has been to visit an MGF specialist.
The inlet manifold problem didn't *usually* affect the VVC models.
Have you checked your front radiator fan(s) ? - do they come on as the car warms up ? The fuse for the front fan(s) can easily blow - especially if the fan motor is a bit sluggish in starting up.
I would also check for corrosion in the radiator - they don't last long on the MGF; mine had to be replaced at about 7 years old. If you've not replaced any part of the MGF cooling system then you could well have multiple problems - the underfloor pipes being just one.
Incidentally - my replacement underfloor pipes lasted just 14 months :-(
The recommendations regarding bleeding the coolant system are very important - see scotmech's post.
You're probably considering changing the cambelt for the second time, in which case consider changing the water pump also.
take a look at this MGF BBS forum:
www2.mgcars.org.uk/cgi-bin/gen5?runprog=mgbbs&acce...9
You will find some recommendations for MGF specialists on the above BBS.
Good Luck
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I see you had already posted on that BBS :-)
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There could well be an airlock after the initial water loss, you don't need to loose much to start having problems and they can be a real swine to bleed. I'm not convinced either block or sniff tests are conclusive proof of the condition of the HG on these either, the engine need to be very hot and you need to sniff it as soon as the cap is removed, a reading of as little as 26 ppm on the HC's can indicate problems but after only a few seconds the reading can drop and everything look normal.
Usually on these MG's the rad is in poor condition and its my opinion that this causes a lot of the premature failures these engines have become infamous for, the waterpump is also worth a look because only a tiny leak here can cause airlocks and coolant loss may not be visable if the hot engine is causing the water to evaporate before it hits the ground.
A vastly miss-understood engine and no-were near as bad as people will have you believe
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"A vastly miss-understood engine and no-were near as bad as people will have you believe"
The evidence is out there for those who wish to research.
www.freelanderheadgasket.co.uk/
www.carsurvey.org/
And no doubt many more sites as well.
I wouldn't touch one. My advice is to get it fixed and sell it. A MX5 will give far less hassle.
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I think we frightened him off.
He's not posted here a second time - though he has on the MGF BBS.
I do know of MGFs that are good, reliable cars - but mine wasn't one of them.
I'd go with Xileno's advice.
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Xileno, I'm not going to pretend these don't suffer HG faults or the MX5 isn't a better car but I stand by my comments about the engine being miss-understood. I know garages that won't touch these engines because of previous problems but these are also the same places that use cheap head sets, don't use new bolts and check the head with a straight egde to see if it needs skimming (after all how straight is your edge?).
I often see these K series engines that are still having problems after a HG change because the original cause of the overheating wasn't fixed or its had a cheap job done with corners cut, we give a starting figure of £500 for these but its invariably more.
I alos practise what I preach, we had a K series engined Lotus Elise in our family from new for five years (first my brothers and then mine), it covered 60,000 miles and the engine was about the only part that didn't give trouble!!!
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Yep I agree with motman
These are often misunderstood, I have done so many headgaskets on these I have lost count but never had to do the same one twice, but always used new bolts,proper head set, head skim, new belts & water pipes & stat evry time,bit expensive but then reliability proved I was right.
I scored on doing these because so many garages wouldn't touch them or would only fit a new engine!
Had one freelander & one 75 which had to have new engines due to owner driving them too far with no water but 100% sucess rate on HG changes
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