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MG MGF Technical Hmmm.... mystery coolant loss... BBS discussion at MG-Cars.info
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MG MGF Technical - Hmmm.... mystery coolant loss...
| Afternoon folks, I was driving in this morning and the water temp guage was going a bit nuts.... stopped in traffic and it wandered upwards towards the top... then pulled off again and it went straight back down to the normal... So took a look in the expansion tank at lunch and whoopy do... no coolant... I've filled it up again with just water at the moment... took it out for half an hour and all seemed ok... no fluctuation in temp guage... the expansion tank showed no signs of contamination and the oil and dipstick look fine. I'll have another look at the end of my day to see if any more coolant has gone but there's definately something odd as I know it's not supposed to just dissapear. Think I might be off to MGR or B&G in the morning If it's the underbody coolant pipes will I be able to see it on the floor after a while? '99 MY2000 VVC by the way... And had an HGF back in July/August - but not a "spectacular steam" one... no cross contamination of oil/water. There is also no burnt coolant smell like there was just before the HGF was diagnosed... Chris. |
| Chris Tromans |
| Sounds like the fan didn't spin up, leading to boiling coolant and loss via the pressure cap. Check the fan fuse |
| Will Munns |
| Which one is that Will?... I haven't got my manual on me or my rave cd... just give me a fuse number and I'll nip out and have a gander... Chris |
| Chris Tromans |
| http://www.mgfcar.de/schedules/sb13.jpg Under bonnet fuse 6 Passanger compartment fuse 15 |
| Will Munns |
| Fuse locations: http://www.mgf.ultimatemg.com/group2/common_problems/hgf_pages/related_problems_overheating.htm |
| Rob Bell |
| #6 under bonnet, is #2 in the owners manual btw. Change if 15Amp to a 20Amp immidiately in any way. |
| Dieter K. |
| Guys, The fuses all look ok... I'm going to drive the car back home again this morning and then give it a check over this afternoon... I will let you know if I find anything.... just took a look in the coolant... no discolouring or anything... looks bright green... Chris. |
| Chris Tromans |
| You should check, whether the front fan works. Easy mode: Lay under the car front. Get your hand up in direction fan vanes and try turning by hand. Does it run free ? Then let the engine idle for up to three quarter hours, and it should come off. Dificult mode: (See Robs link above) Dismantle the engine cover plate under the rear window. Locate the brown coloured sensor, switch ignition on, pull the sensor connector and the fan must come off. |
| Dieter K. |
| The engine has to be running for this to work |
| Will |
| Thanks guys, I might f@rt about with this tomorrow... never had the engine cover off before so that could be fun... or interesting... whichever way you want to look at it... Cheers Chris. |
| Chris Tromans |
| Any news Chris? |
| Rob Bell |
| Rob... sorry nothing new really... had no chance over the weekend to look "under the hood" (or boot in this case)... Since I filled it up on Friday, I'm sure its gone down a bit again but not by much... with me having no spare time at all to myself this week I think I'm going to have to drop it down to B&G for a day and get them to have a check over... that is unless I can sneak out of work early today while my boss isn't watching... Will keep you updated... Chris. |
| Chris Tromans |
| Relating to the above... has anyone got any good photo views of the underbody coolant pipes and what I'm looking for if corrosion to them is letting the coolant out... same goes for the hose clips... how many are there I need to check and got any pics of them? Cheers Chris. |
| Chris Tromans |
| Chris, Have a look at my site at www.apttony.co.uk and look down the contects list for 'Heater Pipes - underfloor' Tony |
| Tony |
| It's worth having at look at the coolant pipes under the inlet manifold as well as the manifold itself. I had to replace all. Underfloor pipes, manifold gasket and the pipes to the thermostat, everthing was leaking. I have a photo of this but no site to show it. |
| Ken Waring |
| Ken... can you email the photo to me... Cheers Chris |
| Chris Tromans |
| Chris, You should have mail. I've had a few problems sending large attachments since I installed a new version of Norton AV. If you don't receive it give me nudge and I'll have another go. |
| Ken Waring |
| Ken, got the image thanks... All, Took a good look under the car yesterday and the pipes look fine and I couldn't see anything wrong. I can't see evidence of coolant escaping... Also took a look at all the hose-clips and I was suspicious of one... as I was looking at the top of the engine from the back it is down the right hand side and is where the coolant pipe connects to the engine block. A picture is as follows: http://pc14.hyperknowledge.com/velma/coolant/connection.jpg My question is should the coolant pipe be pushed on further than that? it looks odd to me... Cheers Chris. |
| Chris Tromans |
| thats prolly fine, no crusty marks etc. |
| Will Munns |
| Hiya Chris - Don't know if this is of help, but... Had noticed I'd being topping the coolant in our 2001 'F' a bit over last 6 weeks or so & had it on the list to look at during pending holiday. In March, had the car serviced by our local MG dealer (canny little family run affair)... anyway, they replaced the pressure cap on the coolant header tank. Just yesterday (Sunday 18 Oct), ground to a halt in a car park, dissapearing in a large cloud of steam. RAC got us back to same MG dealer. Just collected car, who had done pressure tests etc, & found the new cap to be faulty - said they'd had a few the same. For @ 3 quid might be worth a try... Until this I had wondered about the pipes leaking. (ps thanks to the guys in an F behind us who stopped to offer help!) |
| Dave Smithson |
| Dave or anyone, Can they pressure test just the cap to see if thats the problem? Or is it just buy a new one and wait and see....? I'll go down MGR at lunch today.... 3 quid.. is that all they cost? Chris |
| Chris Tromans |
| yes they can test it - they use the same pump as for the cooling system (just a diffrent adaptor) |
| Will Munns |
| >> I'll go down MGR at lunch today.... 3 quid.. is that all they cost? << Yup, that sounds about right. Halfrauds also sell them for similar money (although a slightly different design). |
| Rob Bell |
| Ken, Chris, may I get permission to include the picture to the coolant bleed webside ? It's just great and showing where to blow the jiggle valve free if the engine stood _dry_ for a longer time. |
| Dieter K. |
| Dieter, You can certainly include mine... it took a lot of arm bending through the engine with a digital camera to get that shot! Cheers Chris |
| Chris Tromans |
| Chris, Your picture of the hose connection appears to show that the aftermarket clip is not square on the hose so that if it does not leek now, then it will probably in the future. I would suggest releasing it, check for adequate engagement and refit. Who did your HGF repair ?? Geoff F. |
| G. Farthing |
| Geoff, Marshalls MG Rover, Cambridge did the HGF repair a few months back... Thats what I thought about the clip as well... if I release it, could I not possibly introduce air into the system? Chris |
| Chris Tromans |
| The new expansion tank cap is on by the way... so I've written a line in pen on the tank to check how the level goes over the next few days... Problem is now, that when I needed to fill it up the other day, I only added water (no coolant available in my office!) so I'm guessing it needs a full bleed and refill? Chris. |
| Chris Tromans |
| After the tank emptied, I think you need to assume that air was allowed into the system. A bleed would be a good precaution - Dave's instructions are here: http://www.mgf.ultimatemg.com/group2/common_problems/hgf_pages/coolant_bleed_procedure.htm If you've only added a couple hundred millitres of water, then I wouldn't worry about the antifreeze concentration too much - when you do the bleed you can always use the antifreeze concentrate. :o) |
| Rob Bell |
| I would agree with Rob BUT I would suggest that you give it back to Marshalls with your problem as if that connection is as bad as the picture indicates then they need to know. Is that an indication of the quality of the rest of the job ?? Geoff F. |
| G. Farthing |
| Geoff, I get your point... would they have undone and removed that connection when they fixed the HGF? Chris. |
| Chris Tromans |
| Hmmm - what's the News then Chris out of interest? By the way, my wife Pollie just got her ZR back from same dealers after it's second annual service. One of the things replaced - pressure cap....! (Topped up the coolant an odd time, but not excessive) Would one from Halfords be more reliable I wonder... Does this happen with other manufacturers?... |
| D Smithson |
| The Halfords is said to be the same Q. Might be better, who knows. However, I'm on the 5th _cap_ since 1998 ;) Three of the new reworked (former white stain marked) since y2000 with my newer MGF. I always have a spare in the bonnet :) My theory is on one hand that the cap fails and breaks, - when coolant level is topped up to high and/or on the other hand, - when the coolant starts excessive boiling due to problems with front fan fuse No2 (or#6), gone thermostat, broken coolant sensor, blocked radiator or ... HGF. |
| Dieter K. |
| Folks, After replacing the cap on the coolant tank... it does seem to be staying at the same level all the time now... which no doubt means it was a faulty cap. Just got to get the bleed and refill done now... going in this week hopefully. Chris |
| Chris Tromans |
This thread was discussed between 08/10/2004 and 25/10/2004
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