Engine overheats, passenger side fan spins slowly?

GAMY0524

MEMBER
2000 VOLKSWAGEN CABRIO
2.0L
4 CYL
2WD
AUTOMATIC
156,000 MILES

When the A/C is on, the engine temperature rises to about 3/4 in the gauge. Normally it only goes halfway. When I check the engine, the coolant fan on the left side (driver's side) is spinning. The fan on the right side (passenger side) spins very slow like it has no power connected to it. Is this normal? Do I need to replace the slow fan?

Thursday, August 18th, 2022 AT 11:32 PM

3 Replies

BORIS K

MECHANIC
836 POSTS

Hello,

The "slow" fan should be spinning at the same speed the main cooling fan is running.
The secondary fan is belt driven off the primary fan, hence the lack of power cables.
The belt runs on a pulley on the tip of each fan and has no tensioner, see image 2
Ensure that the secondary fan is spinning freely and that there is no play in the fan blade.
The most likely scenario is that the drive belt is missing.

See image 3 for an exploded view, item 4 is the drive belt between the fans

If the secondary fan is in order, I would suggest replacing the belt.
To access the front of the fans the fan cowling should ideally be removed.
I have replaced the belt without removing the fans by accessing the front of the fans through the gaps of the blades, it is fiddly but can be done.

Hope this helps.

Cheers, Boris

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