Coolant leaking?

[JamesG]

I checked my coolant level the other day and it was below the low mark, so I filled the expansion tank back up to full. Checked again a few days later and it was back to below the low mark again. It's done this a couple of times now.

 

I did a quick search and someone had suggested checking the radiator cap (the rubber bit looks okay - but I don't really know what to look for), and the oil filler cap (which also looks okay to me - no gunge or anything on it).

 

The level in the radiator is nearly up to the top when cold.

 

Any ideas what the problem is? Might it need a new radiator or a new water pump or something? Are these really expensive?

 

Cheers

 

James.

[Bobbeh]

I've had the exact same problem.. no leaking or signs that the cap is faulty. Its weird.

[Terminator]

I've had the exact same problem.. no leaking or signs that the cap is faulty. Its weird.

This is quite common on Jap cars, when the cap releases pressure too early the excess is vented into the expansion tank and if that fills, out on to the road as you are moving. When the system cools the system draws from the expansion tank so the rad looks OK but the tank looks low.

 

I would say 90% its your cap at fault..

[JamesG]

Thanks! I'll get a new radiator cap and see if that fixes it.

[Rob]

Coincidentally, mine has been leaking for a long time now. Toyota dealer could find no leaks but all the mulched up leaves at the bottom of the radiator front are constantly damp. I reckon its leaking into there and thus never shows itself like a split hose type leak would.

 

Could be the same with you?

[hadyn]

did the rad cap fix it?

[Nic]

Also make sure that your cooling system is full to start with, by filling (whilst cold) through the rad cap. Once the cooling system is full, fill up the overflow bottle. If the cooling system isn't full to start with, it could just be that the fluid in the overflow bottle is getting drawn back up into the system.

 

edit: Just realised this is an old thread...