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VZ over heating

Cams vz

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Hi guys and girls I have a VZ alloytec 6 been driving for 2 years without a problem and today it got hot overheat came on dash and Auto Trans light on after I let it sit for a while opened the radiator cap and no water but has water in overflow bottle,,any ideas please
 

DavesSV6Tonner

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Hi guys and girls I have a VZ alloytec 6 been driving for 2 years without a problem and today it got hot overheat came on dash and Auto Trans light on after I let it sit for a while opened the radiator cap and no water but has water in overflow bottle,,any ideas please
Fill up the cooling system with water and without starting the engine look for signs of water dripping, trickling or pouring from the engine or radiator.
I'm thinking the plastic radiator tank might have split suddenly draining all the coolant.
 

Cams vz

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Fill up the cooling system with water and without starting the engine look for signs of water dripping, trickling or pouring from the engine or radiator.
I'm thinking the plastic radiator tank might have split suddenly draining all the coolant.
Ok thanks will let it sit for about 5 hours first that should be enough time do you think
 

wannaeatyourbrains

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The system is pressurised and sometimes it only leaks when hot. If you don't see anything coming out cold, start it and let it warm up, and reinspect.

Common culprits are the heater tap, the radiator cap, the hoses (including the one going to the coolant reservoir, which can break where it attaches to the outlet with the cap on it), where the plastic conjoins the aluminium on the radiator itself, and less commonly but still possibly the bleeder and drain taps on the radiator, the water pump and the gasket for said outlet. Could have sprung a leak from the radiator vanes too, I have seen that.

Still having trouble, let it cool down again, drain a bit out of it, pull the cap off of it, block the line to the coolant reservoir with your finger and blow and suck a bit there. If you can suck, she's leaking. Chances are you will hear the bubbling or squealing and pinpoint the location as well.

If you can't identify anything, change the radiator cap. Sometimes they look OK, but are not working. Were not really a good design.

When the radiator cap buggers up, it doesn't leak. It lets water out, but not back in again. The coolant is lost cause your reservoir fills up and overflows through the overflow hole on the side of it. Once you get an air pocket, it accelerates coolant loss.
 
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Cams vz

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Thanks it pushing water out the overflow hoses has pressure could it be as simple as the cap
 

wannaeatyourbrains

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Yes, very likely point of failure. Letting coolant then steam out, not sucking coolant back.
 
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