[Olav]

Some time ago I posted a topic about coolant loss and the sweet smell of it inside the car.
The ones that replied were both convinced of the leaking heater o-rings being the cause despite the fact that there was no trace of water in the footwell or anywhere else.

So I removed the glovebox and with a small mirror and a torch you can very well see the spot where the o-rings sit but no evidence of any residue there. I placed some paper towel under the connection point of the 2 pipes going in and out of the heater, just where the temp sensor is wrapped around it. If there was any leak, it would certainly show on the towels.

After a day of short distance driving with multiple cool downs and warm-ups (when the smell is most noticable) I lost about 200cc of coolant and when removing the fillercap on the reservoir there was a hissing noise. So some pressure was in the system. While doing so the level did rise. But the paper towels were still dry, no trace of a leak there.

Apart from the smell I cannot find where the coolant goes. Has anyone got experience with a leaking heater core and does anyone know where the coolant leaks on or into if the leak would be in the core? Or any other suggestions are greatly apreciated.

Regards, Olav

 

[Jos Geuze]

Hi

The heater/AC unit has drains towards the transmission tunnel lying under the car you can see them with a torch light. Any moisture from leaking should end up in a puddle under the car, unless the leak is very small and evaporates during running down over the heater, which could explain the smell of the coolant.

Opening the cap right after a stop will always release pressure. The system is designed to be slightly pressurised. As long as you are able to squeeze the coolant hoses with ease all should be good.

Best regards

Jos

 

[Olav]

Thanks Jos,

With residual pressure I meant after cooldown of about 6 hours.

I'll have a look under the car. I saw a picture of these drains in the 'repair' section of this site.

 

[paul.adshead]

Apart from the smell I cannot find where the coolant goes. Has anyone got experience with a leaking heater core and does anyone know where the coolant leaks on or into if the leak would be in the core? Or any other suggestions are greatly apreciated.

There's a new heater matrix going in mine in a couple of days.

For me, I have slow coolant loss from the header tank and a smell of coolant, after about 10+ mins of running. If I have the HEVAC on "LO" (- where the flaps block air going through the matrix), then there is no smell. But if, after having it on "LO" for a while, then increase the temp settings, then there is a horrible smell of coolant. The matrix is leaking coolant vapour into the HEVAC box, then when the temp flaps are opened, all that coolant vapour is injected into the cabin. Nice. I've now lost soo much coolant (due to top-ups every few days,) that my "coolant" is now water - it's not green any more.....

Does anyone know if ethylene-glycol can be ingested from the vapour? If so my liver is screwed. Should this happen, is the body capable of removing the ethylene glycol crystals over time, or do they just stay there forever?

I don't think you'll find any trace of your coolant loss. The stored heat in the heater matrix will just evaporate it off into the HEVAC box - especially if it is a super-slow pin-hole leak.

The part number is STC3261, it's about 200 quid to buy ,and a pain in the rear to change.

 

[Olav]

Today, before reading the new post, I checked the same thing. Putting it on low and leave it there for a while and then increasing the temp settings all of a sudden.

I went to a specialist and we soon agreed on the matrix leaking. BUT....

As I started the engine to go home again the startermotor encountered some serious resistance just about when the rest of the cylinders took over and the engine was running. While driving off I noticed some condensvapour in my rearview mirror coming from the exhaust. That's o.k. when cold but the engine was allready on operating temperature for about half an hour.
I've parked it on the driveway and it will not start again due to the build up of water on top of one of the pistons, The starter just cannot cope with the force.
It has done 108000km's, that's roughly 67000mls and as you can read on the RPI site that's about the time almost all blocks crack. If I'm lucky it is a blown headgasket. If not you'll be seeing my name on this forum more often at various stages of the rebuild/exchange.

Olav

 

[TerryY]

When I first got mine I had to add coolant to the expansion tank every day. One thing that I discovered is that if I let it go for 2 days it lost a lot less on the second day. I put a towel under the little overflow tube and it was wet every day if I filled to the cold mark.

The solution was to lower the level in the expansion tank until it no longer spit coolant from the overflow tube. Then I marked the tank with a pencil mark and filled to there.

After replacing the heater matrix and o-rings the level stays the same for months. But if I fill it cold to the cold mark again it only takes a day to come back down to the pencil mark.