tomcat59alan
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Have you taken the rad off to check the condition of the fins and to see if it's blocked?
P38 v8 Petrol Overheating
- Thread starter madbrit
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Brand new rad fitted todat
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of course anythings possible, but you can't just 'take the thermostat out'
you could put it in a pan of boiling water then put a bolt through it so it jams it open
its cold on the bottom because the radiator is doing its job, only when the thermostat is fully open (over 96c) will the temp eventually equalise because its cutting off the bypass which is straight from the engine at 90+c
this might help...
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Is the thermost fitted correctly?
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Always a possibility but the hoses are all different sizes (should be)
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The bypass is the important one, goes to the small connection in the centre
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Sorry, the bypass is the one that T's off the top hose
The other small one is the heater return. If these are the wrong way around then that could explain the heater blowing cold when the engine gets up to temp and the thermostat opening, which in turn closes off the bypass. Have a good look at the diagram i posted, hopefully helps make sense of the nest of snakes
The other small one is the heater return. If these are the wrong way around then that could explain the heater blowing cold when the engine gets up to temp and the thermostat opening, which in turn closes off the bypass. Have a good look at the diagram i posted, hopefully helps make sense of the nest of snakes
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I'll have a look at mine over lunch see if i can get a pic for you
dubbleRR
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Unfortunately ,heaters going cold is a sigh of gasket failure
as air in the system finds the highest point , the heater matrix ,causes an air lock ,air expands with heat ,water gets pushed out ,try running it with the cap slack loosened might let some pressure, air out ,,I see you said you tested the water for gasses ,but iv never really trusted them ,if its an old test kits....
as air in the system finds the highest point , the heater matrix ,causes an air lock ,air expands with heat ,water gets pushed out ,try running it with the cap slack loosened might let some pressure, air out ,,I see you said you tested the water for gasses ,but iv never really trusted them ,if its an old test kits....
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You can run up to 90c with the cap off, there shouldn't be any bubbles
As I said before I have had the head gasket done or rather head gaskets a few months ago and it’s been running fine but it is bubbling with the Off and pushing water out or was until I forced water through the matrix going for a drive now see if makes a difference
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I'd think you'd get bubbles all the time.
If you run it from cold with the cap on for a few mins then leave over night, is there still pressure in it? If so that's the tell
If you run it from cold with the cap on for a few mins then leave over night, is there still pressure in it? If so that's the tell
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Can't get a pic but it should be quite obvious i think if it's wrong
Hope you have good news after your drive
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On a separate note had random issues which i didn't prove, but narrowed down to a crack in the block that only leaked exhaust gases into the coolant over about 85c. The thermostat was drilled and engine temp rarely got over 70c
