Radiator fills up water reservoir and engine overheats. What's the cause of this.

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AlfredMichael
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Radiator fills up water reservoir and engine overheats. What's the cause of this.

Post by AlfredMichael »

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Bear
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Re: Radiator fills up water reservoir and engine overheats. What's the cause of this.

Post by Bear »

Hello Alfred.
There is a pressure leak somewhere in the cooling system. Check the radiator cap, should be sealing well. The rubber seal on the cap should be good. Look for minor leaks on the pipes. Possible head gasket blown. A radiator shop can check that out by using a dye test.
Hopefully others may provide some feedback as well.
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Re: Radiator fills up water reservoir and engine overheats. What's the cause of this.

Post by Mud Dog »

Most often head gasket or sometimes even cracked cylinder head. in such cases exhaust and / or compression gasses are entering the water jacket and pressurising the cooling system to the point that the coolant is forced past the cap, into (and overflowing) the water reservoir bottle.

There are a number of other possibilities that stem from inadequate cooling and the coolant starts to boil inside the motor, again over pressurising the cooling system with the same result.

As mentioned, the dye test is the first logical step. This will determine whether it's the first case scenario above or if it's just from overheating alone.

First case scenario means strip head off .... usually if it's gasket it will be obvious, if not then the head pressure tested / x-rayed for cracks.

Second scenario is a case of checking all cooling system components - pump, thermostat, radiator not clogged, radiator fins not choked (restricting airflow), radiator fins not corroded, visco fan and of course (as mentioned) radiator cap.

Have the test done first. :winkx:
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Re: Radiator fills up water reservoir and engine overheats. What's the cause of this.

Post by Bear »

Just to add to my comment “Look for minor leaks on the pipes”
From experience on my Honda Prelude I had the same problem driving from Durban to Johannesburg. Problem picked up half way to my destination. Luckily i could see a garage in the distance so with the vehicle overheated I drove to the garage. By the time I reached the garage all the water was drained out. Waited for it to cool filled up water and could not find no leaks. Only after building up pressure I found a pinhole on one of the pipes with a fine spray. Sometimes minor things causes big problems. I used insulation tape around the pipe and drove 300 km thereafter to my destination with a blown gasket and a warped head.
Travel is not really about leaving our homes, but leaving our habits.
Adventure tends to magnify all human emotions.
It's only in adventure that some people succeed in knowing themselves - in finding themselves.
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