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Hi Guys,

Replacing the water pump on my RB25DET

Nissan want $108 for an RB20DET pump, and $159 for an RB25DET pump.

Is there any difference between the two? Can I just use the RB20 one or is there actually a difference hence the extra price?

The part number is obviously different but I have always heard all RB pumps (bar N1) are the same

Some clarification would be great!

Thanks!

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https://www.sau.com.au/forums/topic/190706-rb-water-pumps/
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I thought so to, but another user (grigor) has PM'ed me this info.

There is one 6mm bolt at the top of the pump that is placed differently in the Rb25's.

Some slackers just leave it out and use the cheaper pump and extra sealant.

Some guys buy the cheap pump and slot the hole to make it fit.

There are even el-cheapo pumps that come slotted from China, one pump fits all.

So if you've got an Rb20 or Rb26, you can go to Autobarn and pick up a cheap Rb30 pump as they're identical.

But if you've got an Rb25, you need to go to Nissan or do one of the "modifications" mentioned above.

Not me, I like to do a job once.

It's a bit of a task removing all the timing belt gear to get at the waterpump which is why most owners replace the waterpump, tensioner and idler when they do the timing belt. Some will also do the cam and crank oil seals, but that really depends on the K's of the car.

If this is true then il be getting the 25 one. The project/motor is sort of a no expenses spared kind of thing.

While im here is it worth replacing the idler and tensioner bearings on a 80,000km motor? Anywhere other than nissan that I can get them? ($400+)

Bearings on the motor still feel nice and smooth.

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https://www.sau.com.au/forums/topic/190706-rb-water-pumps/#findComment-3434127
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RB30ET pumps are different to the RB30E, they have a slightly larger impellor and a different blade design to prevent cavitation. I believe the Rb25 uses the same impellor.

I would definately use an Rb30et pump on an rb25 not n/a

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