MGF VVC 1996 : Engine coolant boiling, bubbling and steaming from the expansion tank. The valve in the expansion tank cap let steam out. (cap recently replaced) However, the radiator was hardly warm.
My conclusion: thermostat not opening. QUESTION: Are there any other likely causes I should consider? Should I also replace both jiggle valves? Any other suggestions?
Frank-in-Sweden
Boiling coolant - radiator not hot
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Not many rules really, this board being aimed at technical issues, it shouldn't fall foul (hopefully) of some of the more personal issues that can affect forums.
Rule 1 - Is that you need to think very carefully before posting anything technical or asking anything technical relating to the security system of the car - See 'Security Issues' sticky for more info.
Rule 2 - We (MGF Register) do not support copyright infringement and therefore references to CD ROM, PDF versions or paper copies of the workshop manual (for instance) should not be posted on the forum. We don't want to get into trouble and we'd rather sell you a genuine hard copy through our Regalia shop anyway!
Because advice is honestly and freely given in this technical section, much of it will be amateur experienced based, so any information is given in good faith and is not guaranteed as correct.
Not many rules really, this board being aimed at technical issues, it shouldn't fall foul (hopefully) of some of the more personal issues that can affect forums.
Rule 1 - Is that you need to think very carefully before posting anything technical or asking anything technical relating to the security system of the car - See 'Security Issues' sticky for more info.
Rule 2 - We (MGF Register) do not support copyright infringement and therefore references to CD ROM, PDF versions or paper copies of the workshop manual (for instance) should not be posted on the forum. We don't want to get into trouble and we'd rather sell you a genuine hard copy through our Regalia shop anyway!
Because advice is honestly and freely given in this technical section, much of it will be amateur experienced based, so any information is given in good faith and is not guaranteed as correct.
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frankedwinsson
- Posts: 4
- Joined: Wed Aug 17, 2022 9:06 pm
- MGF Register Region: Europe
- Model of Car: MGF VVC 1996
Re: Boiling coolant - radiator not hot
First. Bleed the system.
2nd Proper MGPart cap. The MG parts fail, forget the aftermarket parts.
3rd, Check the compression pressure of each cylinder. Low pressure indicates a HGF,
Check the radiator for failure by loss of fins on older radiators.
2nd Proper MGPart cap. The MG parts fail, forget the aftermarket parts.
3rd, Check the compression pressure of each cylinder. Low pressure indicates a HGF,
Check the radiator for failure by loss of fins on older radiators.
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RobboMC
- Posts: 1059
- Joined: Wed May 09, 2012 1:36 am
- MGF Register Region: Eastern Australia
- Model of Car: 1999 Mpi
Re: Boiling coolant - radiator not hot
Thermostat seems most obvious but also check water pump is circulating coolant properly,
you should be getting a steady stream back into the reserviour when idling
you should be getting a steady stream back into the reserviour when idling
Re: Boiling coolant - radiator not hot
As these engines, (K-series), are notorious for head gasket failure, you could also get the coolant checked for combustion gases. This is done using an electronic device.
Of course with a cool radiator, thermostat failure does seem the most likely candidate
Of course with a cool radiator, thermostat failure does seem the most likely candidate