1999 Bug Overheating

[cosbug]

Just purchased a 99 bug from a questionable character and finding it continues to overheat and spew coolant. To date I have replaced the water pump, t-stat, coolant senser in driver side lower part of radiator, Aux/fan control module (near underside of battery), and fan relay # 13 in fuse panel under steering wheel. The car still overheats. The fans don't seem to come on until approx 225 degrees F. Bently's book states fan should come on in Stage I at approx 195 and stage II at about 220. I assume it is something to do with the fans not coming at the correct temps, but I have replaced nearly everything in the cooling department and it is getting costly. Any ideas what could be causing this problem.

[hako]

From your description its probable that the radiator is partially blocked due to incorrect coolant (past owners!!!). Did you replace the timing belt when you put the new pump in? Other possible is a cracked head or a leaky head gasket. If you think its fans then hotwire the fans so they run all the time.
Good Luck.

[veedubmechanic]

I can say 99% you most likely need a new fuse pannel with fuse on top of the battery. The fuse overheats and burns/melts the fuse pannel assembly and the fuse pops. Common issue on 98-00 beetles

[cosbug]

Veedubmechanic,

I looked and checked all of those fuses/fuseable links on top of the battery and they all look fine, nothing burnt and power on both sides of all fuses. Any other ideas?

[hako]

Originally Posted by cosbug

Veedubmechanic,

I looked and checked all of those fuses/fuseable links on top of the battery and they all look fine, nothing burnt and power on both sides of all fuses. Any other ideas?

Like I said before, hotwire the fans by running a wire direct to them or shorting the relay so they are powered all the time - if it still boils it is not the fans.
Also you need to check the condition of the radiator and make sure the coolant is flowing freely thru it - you can remove the unit and reverse flush it OR with a cold engine - start engine, place hand on uppermost radiator hose, wait till it gets warm (when thermostat opens), then feel with your hand on the fins as the hot water travels down the radiator to the lower hose. The radiator should get hot all over...not in patches which indicates blocked tubes. (this method also works on model T's).
Is it at all possible the thermostat is installed wrong way around?

[veedubmechanic]

Have you replaced the coolant temp sensor on the coolant hose by the driver side of the cylinder head?

[Overheating99VW]

Originally Posted by veedubmechanic

Have you replaced the coolant temp sensor on the coolant hose by the driver side of the cylinder head?

A year ago, my wife's 99 Beetle (with only 34k miles) overheated going into the city of Lake Havasu, AZ.

We removed the thermostst housing ourselves as it got so hot it cracked and was leaking. We repaired it with JB and reinstalled it without the thermostat hoping this would allow us to return home OK.

No such luck. We ended up taking it to a local repair facility there. In addition to the theromstat & housing issue, they found the [plastic] water pump was completely destroyed.

The system was backflushed, radiator pressure-checked, a new thermostat & housing and a (metal vane) pump were installed along with the required VW coolant. Afterwards, the car would idle for hours without overheating, but would overheat after driving only 5 ~ 10 miles.


A So Cal VW dealership service manager told us to bring it in as is was still under the 100k drive-train warranty, so we trailered it there. A week later, the dealer informed us that the warranty was void due to a substance called stop-leak being introduced into the cooling system. They said the tell-tale sign was a gray powder substance coating the insides of the cooling system components.

Interesting to note, we had noticed a gray powder residue on the interior of the thermostst housing and coolant hoses prior to leaving it with the repair facility in Havasu, so the problem with the stop-leak substance had to have occurred prior to the inital overheating problem in Havasu.

We just started to look into repairing the problem again a week ago. There is a smell of coolant and steam emitting from the tail-pipe, so it looks like the head gasket is gone.


My wife had always had the car serviced at 'Certified' VW dealers since she bought the car brand new, so we question 'How could this happen to a new car?'

Could someone at a VW dealership have punctured the radiator while replacing a foglight on the car? ... then put stop-leak in to cover up their neglegence instead of replacing the radiator?

The reason I ask is that one dealership said they had to disassemble the entire front of the car to replace a broken foglight. When we received the car back, they had broken the right headlight housing and forgot? to reinstall the hood release mechanism. Poor workmanship is the only logical reasoning I can think of as to how any cooling system damage could have occurred.

Also, after reading similar cooling issues on this forum, was there a recall for the plastic vane water pumps? We don't see anything relating to a recall for a water pump in my wife's documentation on the car ...

Thanks ...