L20b Loosing radiator fluid??

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rob.121
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L20b Loosing radiator fluid??

Post by rob.121 »

Hi all, my L20b 2L 4cyl, has been spitting out the overflow bottle and most of the top tank of coolant. I dont use the car much but its done this twice now. Gave the system a bleed up to operating temperature last time couple of months ago but seems to have done the same thing again. No water in the oil and dosnt appear to be any oil in the fluid thats left in the radiator. no leaks eithier

Any ideas on what could be causing this appreciated!


cheers 8-)
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classicdat
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Re: L20b Loosing radiator fluid??

Post by classicdat »

Bit of a worry, hope it's nothing serious.
Does the car start nice when cold? If it starts on 2-3 cyl it is another sign of a blown head Gasket.
Quick check. run up to temp with the radiator cap of and radiator full. With Thermostat open put engine under load at about 2500RPM if it burps out the radiator this suggests that combustion gases are getting into the cooling system.
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rob.121
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Re: L20b Loosing radiator fluid??

Post by rob.121 »

Starts fine when cold, fires on all 4, but it does have a decent coil and new points etc so that could mask the problem slightly maybe?

but il try re bleed the system then open the cap and load up a 2.5k as suggested and see what happens. Temp isnt irregular when driving on the factory or aftermarket temp gauges. when i bled it last time it seemed to take forever for it to stop bubbling up.

hopefully not the head gasket but i cant think of anything else that could be causing this
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classicdat
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Re: L20b Loosing radiator fluid??

Post by classicdat »

I'm not sure what you mean by Rebleed, but would recommend you don't take the cap off hot, heat it from cold with the cap off. Safer, for you and the engine
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Re: L20b Loosing radiator fluid??

Post by Bartman »

See if you can find a compressor fitting with a spark plug thread on it. (Like the kind you'd use to change the valve guide seals) Then you could pressurise each cylinder one at a time. Do that with the rad cap off, and if it blows coolant out when you put 120spi on it, then you've found your problem.
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rob.121
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Re: L20b Loosing radiator fluid??

Post by rob.121 »

sorry, wrote that wrong, i meant re bleed the air out with the cap off up until operating temp, then give it the 2500 rev.

I dont have a suitable compressor fitting but thats another good idea i could look into

thanks for the help 8-)
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torqued
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Re: L20b Loosing radiator fluid??

Post by torqued »

Whats radiator cap like? Could just be fucked not holding pressure.

A better method than pressurizating the motor is to use tee-kay head check. Does all at once with less effort

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rob.121
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Re: L20b Loosing radiator fluid??

Post by rob.121 »

Radiator cap is new, along with the radiator itself. what is tee kay head check?
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torqued
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Re: L20b Loosing radiator fluid??

Post by torqued »

Its device that sits on the radiator filler neck. You fill it will a special green fluid. If the head gasket is leaking into the cooling system
the CO2 gas turns the fluid blue. Or vise versa I can't remember
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