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coolant finding its way into the expansion but not back again?


cookci
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the coolant from my radiator pushes its way into the expansion tank overfilling it?

 

the radiator is left with air at the top. I either have to refill the radiator or leave it running with the rad cap off. This happening?

 

 

please help. i fear the worst... although the heaters blow warm and there is no leak in the cockpit.

 

:search:

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An air lock in the coolant system????

 

Use a poweraid (sp) drink bottle and top the coolant up while running at idle with the heater on full. Give the top hose a squeeze now and then and make sure it gets to proper operating temp. Use the poweraid bottle as a header tank and keep it about 1/4 filled so the rad is totally full. Also park on a slope & make sure the front of the car is at the high end to encourage trapped air to move uphill to the rad.

Worth a try for 20 mins work?

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i would flush the coolant from the car with some sort of radiator flush (forte)etc

then drain the coolant system down and replace the coolant with fresh stuff

it may just be a slight blockage

oh and remember to use toyota forlife coolant

the gaskets dont like antifreeze!!

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the coolant is nice and clean as i changed it about 3 months ago. its been fine up until a couple of weeks ago though...

 

 

have given it another bleed as suggested k14 sup. seems there was alot of air in the system...

 

will post back after a day of 2 with results

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I've had/having overheating problems in the summer with the air con on, and parts of my rad are stone cold. Is this not a blockage that can be flushed out? Or am I likely to need a new rad? Sorry to sort of hijack your thread, but defiantly check all over the rad to make sure its the same temperature.

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I've had/having overheating problems in the summer with the air con on, and parts of my rad are stone cold. Is this not a blockage that can be flushed out? Or am I likely to need a new rad? Sorry to sort of hijack your thread, but defiantly check all over the rad to make sure its the same temperature.

 

What parts are stone cold??? Have you ever used one of those *SHUDDER* rad weld products?? What coolant are you running/have you previously run?? What's the colour inside the rad (rusty/creamy/clean)??

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What parts are stone cold??? Have you ever used one of those *SHUDDER* rad weld products?? What coolant are you running/have you previously run?? What's the colour inside the rad (rusty/creamy/clean)??

 

I've not used a rad weld type product, and use Toyota Red coolant. I've just ordered some more ready for the flush. If I remember rightly there are cold patch's around the rad towards the bottom I believe. Maybe I should use a rad flush product before the change?

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. If I remember rightly there are cold patch's around the rad towards the bottom I believe.

 

Sometimes there are cooler patches towards the bottom as that's where the cooled coolant flows out & there are higher flow areas across the radiator than others.... but it shouldn't be much different??

 

Try a twin pack flushing thing. Halfrauds do one that I tried the other week. No problems. Try and reverse flush the rad too by stuffing the hosepipe in the bottom pipe of the rad, sealing it in there and then giving it full blast.

 

The twin pack flushing stuff takes a while as you need to run then flush then add part 1 then fill then run then flush then fill and flush then add part 2 than fill and flush ......... you get the idea!

 

How did the bleeding work??? Has it stopped burping coolant out??

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Guest Intrinsic

http://www.tegger.com/hondafaq/overheating/index.html

 

Air in radiator, but expansion reservoir full

 

Coolant leak

Too much air in system after fluid change

Bad radiator cap

Bad seal between radiator cap and expansion reservoir

Failed head gasket

 

When the gasket goes, typically the first thing that happens is that combustion chamber gases are pumped into the water jacket. You will see this as bubbles in the expansion reservoir. This will quickly lead to low coolant level in the engine, and overheating at idle, even if the fan comes on, since the water pump can't move the coolant around properly any more.

 

If the engine starts to overheat at idle, or in heavy traffic, and the gauge goes down when you rev it, the coolant is low.

 

The symptoms are similar to a failed rad cap. If you top up the rad, replace the rad cap and the problem persists, the head gasket is definitely questionable. To confirm this, a garage can apply a pressure test (NOT a "compression test"), where air is blown into each cylinder in turn until the technician sees bubbles in the radiator. If no bubbles are seen, the problem is elsewhere, such as an external leak.

 

This can be accompanied by an expansion reservoir level that is much higher than normal, and which does not go down once the engine cools off.

 

If you choose to simply add fluid and ignore the issue, eventually oil and coolant will begin mixing together, and coolant will get sucked into the combustion chamber. Ignoring this is a good way to toast a perfectly good engine. Get it fixed early and there will be no further issues.

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