Accord 2000 4 cyl. coolant leak

My 2000 Accord (60k miles) is occasionally losing coolant externally;
i.e. once in a while there is a small puddle (2 inches in diameter) on
the driveway; I can't seem to see where it's coming from. All hoses
appear to be in good shape; temp gauge remains the same as always
(just under half-way). When it is parked after driving, there is the
distinct odor of coolant, but can't find the source. Perhaps a pin-
hole leak in the rad or a hose? What about the rad cap - after 8
years, should it be changed?

Dealer ran a pressure test at last service in June and said all was
normal. Any ideas?

Thanks!

 

Weep hole in water pump?

 

The easiest way to find the leaks is to look first thing in the
morning after it sits all night. A leak this small will evaporate
immediatly on a hot engine, but there should be a tell tale stain or
even a wet spot on the engine/radiator/hose after it cools. If its
the water pump, look for wetness at the bottom of the timing belt
cover or the bottom of the crank pulley.

This, of course, assumes the cap is still good and is holding
pressure. If you are not finding anything in the morning, it might not
be. 8 years is probably beyond the normal lifetime of a radiator
cap. Try a new one, but don't be surprised if there is a catastrophic
failure somewhere in the cooling system a couple of months after
changing it because the weak point in the system will no longer be the
cap.

 

I would suggest to wash your engine bay clean first.
Next day after washing it you will see new stain,
usually whitish color from the evaporated coolant.

I keep my engine bay washed once/twice a year
and all such small leaks are very apparent then
on a clean engine body.

 

Thanks for all the suggestions; hadn't thought of the water pump weep
hole; the pump was changed last winter along with the timing belt job;
perhaps there's an issue with the new pump.

Cheers,

 

| 8 years is probably beyond the normal lifetime of a radiator
| cap.
Then why service schedule does not specify when to change ?
The rubber gasket of my radiator cap made by Toyo in 1990
is still fine. Leaky rubber is hard & has fine cracks, this
gasket has no such cracks, neither do the rubber hoses made
by Yamashita in 1990, all are still soft as new, on my F20A.

 

Its not the rubber that fails, its metal fatigue in the spring. As
for why its not in the service schedule I can only guess that its
considered a normal maintenance item, like checking the air in the
tires & checking the level of the oil. I am fairly certain that if
you pull the cap from any random 8 year old car on the street and test
it, the probability is high you will find it is not holding specified
pressure.

 

Also, there might be some catastrophic failure of the cap
like the leak to the overflow bottle (bleeder fallen off?)
and then you have no pressure in the system, at all...
This is what has happened to my cap at my 1995 camry.
New cap at the local toyota dealership was only $19...

 

not true. or at least, spring failure is very rare compared to rubber
failure. older cars, rubber failure is pretty much certain.