'07 Honda CR-V, 2.2 Diesel. - Coolant expansion tank keeps filling up.

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Thu 22 Apr 2010 23:22
'07 Honda CR-V, 2.2 Diesel. - Coolant expansion tank keeps filling up. - eddie12

I have recently noticed that the coolant in my expansion tank keeps filling up, even after I have extracted sufficient coolant to obtain the level between the min. and max. marks.

Can any one offer any advice on what the problem might be please?

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Fri 23 Apr 2010 00:47
'07 Honda CR-V, 2.2 Diesel. - Coolant expansion tank keeps filling up. - 1litregolfeater

I can only imagine you're letting air in somewhere, and gradually developing an air lock. Hope it's not your cylinder head gasket. Check the seals on any radiator cap type seals and any hose joints that look high enough to have a leak without blowing water out.

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Sat 24 Apr 2010 09:40
'07 Honda CR-V, 2.2 Diesel. - Coolant expansion tank keeps filling up. - Simon

Is the water turning a murky colour?

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Sat 24 Apr 2010 23:50
'07 Honda CR-V, 2.2 Diesel. - Coolant expansion tank keeps filling up. - eddie12

Is the water turning a murky colour?

No, coolant sample is a nice blue colour, and there are no apparent leaks that I can find.

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Sun 25 Apr 2010 19:54
'07 Honda CR-V, 2.2 Diesel. - Coolant expansion tank keeps filling up. - maximus

Had similar situation on Primera. It turned out that the cap on the radiator was the cause.

£3ish and problem solved. It took me a while to find out my problem as I assumed it was a leak

p.s. When I inspected original cap I could not see anything wrong, it must have been the pressure.

Edited by maximus on 25/04/2010 at 19:57

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Mon 26 Apr 2010 16:01
'07 Honda CR-V, 2.2 Diesel. - Coolant expansion tank keeps filling up. - eddie12

Update; Dealer did a pressure test to-day, and couldn't find anything wrong. I notice that the coolant level is "normal" at present, so I will keep an eye on it and see how it goes. I suppose it's possible that the pressure test could have dislodged an air-lock, so, fingers crossed.

Thank you to all who have replied so far - any other ideas as to possible cause will be most welcome.

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