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4.5 Water pump bearing change?

Posted: 12 Dec 2019 07:14
by Florian320
Good morning!
I have just been to Kruger and had a few occasions where I went through deep water paddles.
The day after I‘d have a bad sound out of the engine bay after starting, most probably from the water pump bearing.
I put some Q20 onto it and after some KM the sound disappeared.
The water temperature was normal, so the impeller always worked.
Anyhow I want to change that bearing now.
My question is: is that possible at all, or will I only get the pump as a whole?
I am also not sure if maybe replacing the water pump is a good idea when having it out already.
What are your ideas?

Best regards,

Florian

Re: 4.5 Water pump bearing change?

Posted: 12 Dec 2019 09:04
by iandvl
If you're going to the effort of taking the pump out, I'd suggest replacing the pump entirely. Might be an idea to do the viscous coupling too if that has not been done before.

Re: 4.5 Water pump bearing change?

Posted: 12 Dec 2019 09:53
by hugejp
X2

Re: 4.5 Water pump bearing change?

Posted: 12 Dec 2019 10:07
by Dungbeetle
Florian320 wrote: 12 Dec 2019 07:14 Good morning!
I have just been to Kruger and had a few occasions where I went through deep water paddles.
The day after I‘d have a bad sound out of the engine bay after starting, most probably from the water pump bearing.
I put some Q20 onto it and after some KM the sound disappeared.
The water temperature was normal, so the impeller always worked.
Anyhow I want to change that bearing now.
My question is: is that possible at all, or will I only get the pump as a whole?
I am also not sure if maybe replacing the water pump is a good idea when having it out already.
What are your ideas?

Best regards,

Florian
Just some experience from my side on my 4.2D:

I had a similar issue and also sprayd some WD40 around there, and at the back of the water pump belt pulley. Long story short the problem came back after a short while. BUT as I discovered later- it was not the water pump bearing. It was the tensioner pulley bearing screaming.

Re: 4.5 Water pump bearing change?

Posted: 12 Dec 2019 10:18
by mvcoller
Replace the complete pump rather.......

Waterpumps are finicky when replacing bearings. You have to heat the bearing to remove it, which invariably damages the seal. The same happens if you have a hydraulic press available and try and press the bearing off the shaft.

Bearings can be found, generally, but seals are not so easy to find, if at all....

It is just not worth the trouble....

Re: 4.5 Water pump bearing change?

Posted: 12 Dec 2019 12:11
by NoPressure
Just for interest sake, how many km is on your 4.5?

Re: 4.5 Water pump bearing change?

Posted: 12 Dec 2019 13:06
by Florian320
Thanks for the replies!
It is just around 275000km.
In parallel I also thought you don‘t f..k around with the water pump.
Funnily my Nissan Dealer offered me a replacement pump not being genuine for around 600 ZAR.
But the pump being quite vital I‘ll go for a genuine one.
In addition I‘ll also replace the thermostat when work has to be done on the cooling system anyhow.

How can I rule out that for sure it‘s the water pump and not the viscous coupling of the cooling fan?
Shouldn‘t that one be silent if the fan stands still, or will the bearing always move?

Re: 4.5 Water pump bearing change?

Posted: 12 Dec 2019 14:52
by iandvl
The coupling will need replacing at some point. And at that mileage, I'd do it anyway. When replacing the thermostat, make sure it works. ie: Boil the kettle, pour boiling water into a coffee cup and chuck the new thermostat in there. It should open up.

Graham also normally removes the funny valve thingy on the thermostat and drills the hole a little bigger. Get hold of him for details about this.

Re: 4.5 Water pump bearing change?

Posted: 12 Dec 2019 16:38
by Peter Connan
I think the chances are 95% that it is the bearing in the tensioner pulley. It is a common bearing that you can get from any Bearing Man or similar outlet, but the guys tend to fit the wrong type of seal (normal single-race bearings usually come in one of three different variations, you need the one with the metallic end caps).

They commonly give issues after water crossings, whereas the water pump doesn't because it is well protected by the pulley.

Re: 4.5 Water pump bearing change?

Posted: 13 Dec 2019 08:19
by Florian320
Hi Peter, thanks a lot for for the advice, also thanks for the other replies!

The sound came from the area of the waterpump quite precisely.
But obviously the bearing of the cooler fan is just in front of it so I can‘t rule that one out.
I guess I can only see who the culprit is by taking them of the car, isn‘t it?

Now as I had my ears on the belts I got the impression that the free wheeling mechanism of the a/c compressor also could have a very slight screeching sound.
Can that one be changed alone or would that mean a new compressor?

I‘d like to get that area done in one move when I have it worked on...