Blown head gasket and other issues

[englishman11]

So, when driving down the freeway my coolant low light came on. I had to get up a hill to a spot where I could safely pull off to the shoulder to check it out (1/2 mile at most). When I started to slow down, the engine died. I lift the hood and my car and noticed that it had puked all of it's coolant out and it was steaming off the engine. I got a tow home and started digging into the engine. I pulled the coolant flange since I figured it wouldn't have survived and sure enough it needs replaced. On top of that, the head gasket seams to be blown since I have coolant on my spark plugs. My question is, where else should I look? I think that the water pump is fine since the belt is still in tact. The timing belt seems to be fine as well. Any advice would be most welcome.

[Smileybug]

I'd check the water pump. I'd bet it failed.

How many miles on the car? If the timing belt and water pump haven't been done yet, in a '98, regardless of mileage, you are long overdue.

[simonsi]

Are you sure it was the warning for low coolant and not overheating?

As it happened on the freeway it cant be down to the radiator fans so that leaves:

1. A leak
2. The pump
3. The thermostat
4. a blockage

The belt being intact means nothing but the first thing to do is compression test each cylinder to show whether you have got a blown head gasket and work from there. My guess is that you have a failed pump, either broken or slipping impellor but you need t determine for sure whether the head comes off BEFORE you change the pump and belt, otherwise you´ll have to do it again if the HG has failed. Renew the coolant with G12 once you have the cause nailed.

[Fl_bug]

Coolant Temp sensor i'm sure too.

Are your cooling fans turning on?

[simonsi]

Originally Posted by Fl_bug

Coolant Temp sensor i'm sure too.

Are your cooling fans turning on?

Shouldn´t think so, it happened on the freeway (so no cooling fans required), and is ACTUAL overheating, not the ECU thinking it is - did you read the thread at all

[70autostick]

A blown head gasket will cause the car to overheat if it eats up enough coolant.

However, chances are, you either had a bad leak or a busted impellar ( Every new beetle is subject to a new water pump before 150k) that caused her to overheat.


You said you drove half a mile while overheating, up a hill, thats not good... I would expect a blown head gasket under those circumstances.

[Pseudotropheus]

Water pump toast. Plain and simple.

Might as well replace timing belt, pump, ECT, flange. Replace with Pentosin or any other VW specififed fluid. Should be good to go. Common problem on these cars.

If you wanna replace head gasket, you can. However, I would dig more to ensure the gasket is in fact blown or no good.

No need to create more work for yourself.

[Fl_bug]

Originally Posted by simonsi

Shouldn´t think so, it happened on the freeway (so no cooling fans required), and is ACTUAL overheating, not the ECU thinking it is - did you read the thread at all

If your cooling fans don't come on to cool the engine down, moving or not, your car will overheat eventually. If you're moving but not moving at a speed high enough to keep the car cool with no cooling fans, then you'll overheat eventually.

A bad temp sensor in turn won't know the car is hot, so won't turn on the cooling fans.

[englishman11]

Thanks for the replies. I'm planning on taking off the water pump tomorrow after work. I have no idea what had been replaced by the p.o. That would be the easiest to check vs pulling the head.

The temp sensor looked pretty rough so I got a new one. Also have a new coolant flange installed and have some G12 on the way.

[Smileybug]

When you do take off the pump, the timing belt comes off too. Might as well put a new one on when you're done with everything.

[simonsi]

Originally Posted by Fl_bug

If your cooling fans don't come on to cool the engine down, moving or not, your car will overheat eventually. If you're moving but not moving at a speed high enough to keep the car cool with no cooling fans, then you'll overheat eventually.

A bad temp sensor in turn won't know the car is hot, so won't turn on the cooling fans.

Any legal freeway speed you are moving many times as much air as the engine needs to keep cool, there is no "eventually" until you come to a stop and need the fans to provide airflow.

The fans use a seperate temp switch in the radiator, the coolant sensor doesn´t come into it. The fans only run when the a/c is on or the radiator is hot, they don´t care about the engine temp, only the radiator temp.

[englishman11]

Well, due to being sick for the last few days I just got the water pump pulled. It has the plastic impeller but it's in good shape, not broken, cracked or melted. Since I'm at it I will be replacing it with a new metal impeller one as well as the timing belt and tensioner.

I pulled all 4 spark plugs and there is coolant on every single one of them. Head gasket is toast. The good news is there is no coolant in the oil. I can be sure the origin of the coolant leak was the flange now. Everything else is in good shape.