WATER PUMP CONCERNS

[Mike Allfrey]

G'dday From The Wet South!

Yes, we had 60 mm of rain yesterday!!

Has anyone experienced this before?

A while ago, while driving in foul weather conditions, the rev counter ceased to register, the engine laboured and the ammeter went beserk, swinging violently from full discharge to full charge, repeatedly. There was also a 'clattering' in the voltage control box. It was too wet, and were too close to our destination to pull over and investigate. Then things stabilized back to normal. It should be added that the headlamps and wipers were in use at the time.

Later, after opening the bonnet, the front of the water pump and distributor were found to be covered in grease. It was a very careful trip home.

The pump was removed and dismantled. The following points were noted:

1. The drive belt showed signs of excessive slippage.

2. The water pump front bearing (Toyo Kogyo) had collapsed and the race cage had broken up.

3. The pressing, 50614, had cut a groove in the front cover.

4. The impeller had scored the rear shroud on the front cover.

5. The rear spindle bush journal had worn 'only on one side'.

6. The spindle was bent.

7. Miraculously the seals held in the coolant!

My initial theory is this:

With headlamps and wipers going the ammeter had shown a slight discharge for a while. I am fairly certain there was, for want of the proper term, an 'electrical lock-up' that stalled the dynamo for a few seconds. Hence no rev counter function, and the ammeter going through its act. The fan belt, being a grippy Gates Hi-torque belt, probably slipped at the least pulley wrappage -- the dynamo. Dynamics may then have taken over and overloaded the front bearing causing the damage to pump components.

Is this reasoning too far fetched?

I will now get back to my alternator research!

Have a wonderful time in Crieff -- wish I could be there!

Mike Allfrey.