Old Library

I've been losing coolant lately, and this morning when starting my car,
I was out of coolant again, and when I took the cap off the overflow,
there was some serious pressure in the system. I didn't think that the
cooling system was supposed to be under pressure when it was cold. Is
that the sign of a bad cap? Or should it always be pressurized?

Steve Houck
'95 Jetta GLX

The system should always be pressurized.

Check your oil, if your mysteriously losing coolant,
sounds like your oil cooler went.

Check the oil for signs of coolant? Isn't that an effect of a bad head
gasket too?
If the oil cooler went, wouldn't the oil temp be higher? Mine is
anywhere from 200-220 (normal from what I've read)

Steve Houck
'95 Jetta GLX

Yes coolant in the oil is common for head gasket failure but
our cars are prone to oil coolers going bad.

Unless you overheated your car, or you got some kind of coolant
leak somewhere.
Oil temperature will change dependant on how bad its leaking.

If you think the pressure is to high check the head gasket. In  the morning
before you start the cold car top off the coolant, then with  the overflow cap
off start the car. If no noticeable bubbles or  coolant goes flying out and
about and the exhaust don't look like a fog  machine. Your head gasket is
probably good. I would get a good flashlight  and check the radiator and hoses for
leaks.
Good luck,
Shawn Loughran

 I forgot something. The 2 times I was loosing coolant, it was leaking out
of a) the auxiliary coolant pump, b) heater core.

-John

 From a seal, IIRC. It was pretty obvious & left a coolant puddle on top of
the transmission.

-John

> -----Original Message-----
&gt; From: Steve Houck [mailto:&#115;houck&#64;entyre<img src=/i/dc.gif border=0 width=35 height=15>]
> Sent: Tuesday, January 24, 2006 5:42 PM
> To: John Tumas; VW Golf; GTI VR6 mailing list
> Subject: RE: [gti-vr6] Cooling system pressure when cold
>
> GOD I hope it's not the heater core. It's only 10 months old. The
> auxiliary coolant pump, that's the electric one on the rear side of the
> head, right? I've suspected that thing, but never had a smoking gun.
> Where was it leaking from out of the pump? I'll take a look around, but
> I've poked around in there, and I didn't really see much of anything.
> The bottom of the expansion tank was a *little* wet, but it didn't look
> like there was a giant leak. Maybe it's that. Too bad I have to wait for
> it to empty again until I'll disconnect the hose and reseat it.
>
> Steve Houck
> '95 Jetta GLX

I called my VW shop, and they offered me a used oil cooler for $50. Is
the oil cooler one of those things that I shouldn't risk buying used? He
said that they've only sold 3 in the whole time they've been around
(longer than the mk3), so (he says) it's not the kind of part that fails
that often. Thoughts?
Steve Houck
'95 Jetta GLX
-not very cool oil edition

1. I would not recommend getting a used oil cooler, just for the
simple fact, of doing the job all over again, to find out
you still have a leak.

2. You can replace the oil cooler without removing the front
end off but it will be tight, you will have to remove
the oil filter housing, which is only 3 bolts to give
you that additional wiggle room.  I have done it this way.
3. You can remove the whole thing and go with an
external oil cooler, which I have also done.

4. Seals, cause OIL leaks not anti-freeze leaks!! The
coolant is in the hoses.

5. Did you check your oil for coolant? otherwise, this
is all a waste.

To check your oil for coolant, you can usually pop the oil cap and look in.
if it looks like whipped chocolate moose, yep, dats coolant mixing in there!

if not, your probably fine on the oil.
to be absolutely sure, drain it and look at it once its out, it will
look like chocolate moose if its got coolant in it.

Conlan