overheating....

[dgcrsn]

I have a 95 golf with the 1.9 and it is over heating. I have replaced the thermostat twice, replaced the rad, fan comes on, rad cap is newer, water pump seems fine. the thermostat is working because the bottom hosegets hot. It will idle fine but builds alot of pressure. but when i take it down the road it pushes out coolant and the gauge rises really quick. It seems to work fine though if i drive with the heater on and keep it under 100kms. nothing is making sense to me....any ideas? thanks

[Quantum TD]

Sounds like a HG. One last thing you might try is to pull the rad, backflush it, and clean the fins with some acid (any rad shop can do it). That will help cooling, but if the fan is working, the switch is new, the t-stat is new, and the water pump is working, then I'd say you probably have a bad HG, or a severely clogged rad.

Obviously, the easiest way to test it, is to do a compression test. Low numbers on adjacent cylinders means blown hg.

Good luck

[jimfoo]

for one thing that worked for me, see this.

[clbanman]

If it is OK when you run your heater, it may well be a heat transfer issue.  Most likely cause is rad -either clogged internally or missing/severely corroded fins.  If the fins feel soft and disintegrate easily when touched, replace your rad.  Otherwise, check to make sure the suction side hose from the rad isn't collapsing or you don't have internal blockage.  The reverse direction flush suggested above may work if it's relatively minor and recent blockage.  Your car likely heats up normally which shows the thermostat is OK at least up to the opening point.  As long as you know the thermostat is opening, the heating shows that the part of the system (rad) designed to remove heat from the coolant is not functioning correctly.  If your heater core can remove enough heat to keep the coolant temps in acceptable ranges at 100km/h, then you don't really need to pull a lot of heat out of the system.

[shegel]

my car was doing the same thing what fixdedc it for me was:

when i took the old radiator out to replace it i found that some mice had made a nest between the ac condencer and the radiator. cleaned it and now its fine

[theman53]

my first rabbit I thought the water pump was working...but sadly it didn't. I had a fairly even stream at idle, but it got hot like yours. When I did the timing belt I also did the water pump * and broke all the bolts that went through*.   After that it never overheated on me again.
        I would stilll check your compression as Quantum said. It is easier than that stinking water pump change.

[dgcrsn]

Thanks for the replys guys. Uh i changed the rad and found out it had wat seemed to be the original rad in it and it seems to be fine now but ill see as i drive it which i cant at the moment because my powersteering pump blew apart today and my clutch cable broke.

[Quantum TD]

Rough week man. Good luck on the rad.

I've heard that if you mix standard green antifreeze with the VW recommended G12 (pink) it will clog up the guts. So, if you've swapped the rad, might be a good time to flush and put in the right stuff. G12 at the dealer is not too expensive: like $15-20 a gallon, and you mix it 50/50, 60/40, or 70/30 depending on climate. Either way, a gallon is all you'll need for one car.

Good luck.

[fastvicar]

G12+ is what I'd go for.  You can mix the "plus" formula with other antifreeze.