I cannot find a suspected SLOW coolant leak. Any ideas?

[968TomR]

When driving home from a DE this past Saturday I stopped to fill up with fuel. I popped the hood to check the oil and noticed a slight smell of coolant. I looked everywhere and could not find anything.

The next morning - after it had cooled - I noticed that the coolant level was just below the minimum level in the expansion tank. I started up the car to go back to the track (after topping up the tank) and experienced some belt whine (as though the belts might be wet).

My problem is that I cannot locate this leak. I drove all day (around 130 track miles plus 110 there and back) and the coolant level never really dropped, but I still noticed the smell.

Can anyone point me to a likely culprit?

Tom

92 968 - Track Toy
99 528i - Family Truckster
96 Saturn - POS

[ballysdad]

pressure test you will find it.. If there is no eveidence under the car it may be the water pump leaking while you are driving, or worse coolant leaking into the oil..

[ballysdad]

After re reading check your passenger footwell for dampness...

[968TomR]

I have no milkshake - so I don't think I have coolant entering the oil. Also, I can only catch a slight whif of coolant and only under the hood. I will check the passenger footwell but I don't suspect it is the heater core.

- Tom

[Rasta Monsta]

I don't mean to talk down to you, but this is a common error. . .by "topped off" you mean filled to MIN when cold, not MAX, yes? Because if you fill to MAX when cold, it will spit coolant out of the overflow, especially under DE conditions.

[968TomR]

Yes - Filled to the MIN level when cold. It was just below there (I would say maybe 1 cm) when I added it on Sunday morning.

Tom

92 968 - Track Toy
99 528i - Family Truckster
96 Saturn - POS

[nightheart]

might get lucky and it just needs a new cap on the expansion tank.

[flash968]

very common to have a leak between cylinders, especially if it is the original head gasket - you will not see any coolant in the oil or oil in the coolant - a compression test should show it though

[968TomR]

But I think I found the problem. See picture posted below.



The fact that I can smell the coolant when I am under the hood makes me think it is more likely that this hose is seeping coolant than I have a blown head gasket.

Here is another shot. I can easily see how this could drip onto the power steering belt and cause the squealing of the belts I experienced.


Here is a picture of the loss after a day at the track in the reservoir.


I really do appreciate all the input. Hopefully I have tracked down a problem that requires either a screwdriver, or more significantly a new hose clamp.

Tom
92 968
99 528i Family Truckster
96 Saturn POS

[flash968]

cool - i hope that's it - a lot of deteriorating head gaskets are popping up, and i thought that could be it, but as i said, a compression test should have shown it if it was

anyway, it looks like you are using either the wrong coolant or using tap water instead of distilled water - that looks like a lot of mineral deposits there

[thekidd]

Definetly clear that shat thats on the water pump hose off. Had trouble with coolent when I bought my '84 a couple months ago. Had coolant leaking, then that hose broke, so I cleaned all the gunk off the water pump, and sinse then havent had to fill the expansion tank back up since. Maybee run the car for a little bit, or take her for a walk around the block, and while the engine is running, check for a leak. Good Luck

[87944turbo]

Hope you found your problem. I had a similar issue and it was an external HG leak that was dripping on the turbo cross-over pipe, so it never hit the ground. Always good to see folks from Indy on here. Were you at Putnam? Plan on getting out there someday.

[rickharrison]

I'd clean it, and drive it a few days to see if it comes back there...you also mentioned a belt whine...could be the water pump starting to go too. They tend to drip/seep onto the t-belt.

Best of luck.

[Slam]

^+1

Whip the timing cover off and check under and around the water pump. May get lucky there and the HG's fine.

[968TomR]

I will certainly check further. The timing belt and water pump are 10k miles and 1.4 years old, so I don't suspect them, but with those items it is always better safe than sorry.

Tom
92 968 Track Toy
99 528i Family Truckster
96 Saturn POS

[ace_944]

Um ok quick question, that plastic part that comes off the hose that connects to the water pump, (i think its some kind of a cut off valve) does it have to be in that position or could it possibly go towards the back of the engine? I only ask cause thats where mine was when I took apart my engine, guess the PO felt like it shouldn't be there. Also what problems would one have if it was placed wrong? Thanks in advance guys.

[TibetanT]

Tom:

Good to hear the water pump and T-belt is fairly new.

However, when was the coolant system last purged? Could also be a bad thermostat causing some grief, as well as like some have mentioned regarding hard water.

As far as the amount of loss from the reservoir, it seems somewhat normal to me.

Also, a bad radiator would cause "smells of coolant" to happen at times. At least that was my experience awhile back with an older 944n/a I worked on. In that case, it turns out the thermostat needed replacement and so did the radiator.

Hope this helps and good luck with that. At least now you know where the smell was originating from.

[944turb0]

I had the same problem last spring, and it turned out to be a belt pulley rubbing against the upper radiator hose. It started as the tiniest hole (and you could smell the coolant) and the belt would chirp because of the coolant seeping onto it. eventually it cut the hose deep enough for actual coolant loss

[flash968]

in 5 years of running my blue 968, i have only had to add a total of about 4 ounces to the system - it never loses coolant - same goes for the year of owning the white one