Every few days I have to fill up the radiator fluid in the overflow tank. It gets to right below where the hose is that leads to the radiator. I'm assuming that its one of three things.

1- Leak in the overflow cylinder
2- Leak in the hose
3- Leak in the radiator

I'm thinking its not in the radiator since the car does not overheat. Any suggestions or test to find out where it might be?

thanks.

 

If there would be a leak, I'm sure it will drip and be noticeable on the ground somewhere, and plus you would be able to smell it. You may not have enough coolant flowing thru the whole system, and the radiator is taking the coolant from the reserve tank. By any chance, did you replace your coolant recently?

 

Do you actually see the coolant leaking? Look under the car. If there is no visible signs of coolant loss under the car, but the bottle keeps going low, it's probably leaking into the motor itself and may be a bad head gasket (uncommon on the VQ though)

 

Yes, it started happening soon after I got my radiator flushed!!

 

OK. Then that explains it. If it was recently flushed and drained, then there must not be enough sufficient coolant running thru the system. The radiator will keeping draining the reserve tank. Just keep filling the reserve tank slowly below the fill line and monitor the tank after every driving cycle (after the engine has cooled). Once the coolant stays steady around the fill line, you'll know you have enough coolant in the system. Quick note... whenever you drain and flush the coolant, it's always a good idea to measure out how much was drained out, so that you have a sufficient idea of putting the same amount back in.

 

You could also have a bad radiator cap. If it's not holding pressure then you will slowly boil off liquid. A cheap fix tho.

When I replace coolant, I run the engine up to temperature with the radiator cap off, topping up the radiator as it gurgles away. As soon as the thermostat opens and you get good flow, all the air gets purged and you can finally fill 'er up and put the cap back on.

Alternatively, keep doing what you're doing and it'll eventually settle down.

 

Your car is probably too young for this. But on my 1990 Maxima, I had a pinhole leak in the coolant bypass hose to the throttlebody. It would not leak cold, and it wouldn't leak fast enough after parked hot to generate a puddle. I would have to refill it weekly.

First I thought it was a blown head gasket, but a mechanic convinced me to look harder for a leak. After getting home from a trip, I had a friend race the motor. Lo and behold I found coolant pulsing out in a needle stream with each rev of the motor.