MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGF Technical - Expansion tank cap

Morning everyone. Just a quick question about the above mentioned cap. After a wonderful run in the sunshine yesterday i parked her up in the garage and was getting the shopping out of the boot when i heard a hissing coming from the cap. I left her to cool down and took the cap off. Coolent level normal and i make sure the cap was on tight. I've ordered a new one from Victoria to be on the safe side but am i being a bit paranoid? Can i use the car today? Is it normal to get a little hissing?

Thanks
M J Smith

Were you driving particularly enthusiastically? The cap's function is to release excess pressure which usually only occurs when the engine is unusually hot - worth checking that your radiator fan is kicking in. Wise move in ordering a new one, but as long as you're not actually losing coolant then no worries about driving it.
Mike Hankin

Learn something new every day! Dumn question, but do you mean the fan in the side vents or is there one by the rad. The rad is about 2 months old. If the 'rad fan' wasn't kicking in would my temp gauge reflect that?
M J Smith

The fan on the side vents is just for cooling the engine bay, the one that should be kicking in is the radiator fan.

The gauge may not show any increase in temperature until the overheat is severe, the fan should kick in even while the gauge reads 'normal'

If the rad was replaced recently, presumably the cooling system was bled at all 3 bleed points? If not you should do this again asap.
Mike Hankin

if youre worried about water loss i would really recomend a water level sensor it comes with a new tank and cap and a bit of peace of mind.

http://bg.mgcars.org.uk/index1.html?o=114943399820284
d l brown

the fan should kick in even while the gauge reads 'normal'

As a new MG F owner, what is a normal reading?
R Miller

The F's temp gauge always, always sits one notch under half way. If it ever moves then something is seriously wrong!
Dave Livingstone

<< The F's temp gauge always, always sits one notch under half way. If it ever moves then something is seriously wrong! >>

I've often wondered why that is. Why didn't they set the gauge so it registers exactly half way as a normal healthy reading?? Weird and quirky I say!!

(Mine is one notch under half way phew!)

Fiona :-<>
Fiona

Well i did go for a long run yesterday and have had no problems at all. My temp gauge did and has always sat just below half way. Water level normal. I've not notice the front fan coming on but it must have done. AND i've a new cap coming on wednesday for more peace of mind (along with my AA warranty of course).
Cheers for the info.
Martin

This thread was discussed between 04/06/2006 and 05/06/2006

MG MGF Technical index

This thread is from the archives. Join the live MG MGF Technical BBS now