How often should the water pump be changed?

[AndysPlit]

.......I'm going through my receipts from the last 11 years of owning my Z, and I discover that the water pump was last changed about 83,000 miles ago. I am about to embark on a 1600 mile roundtrip around the Southwest, as some of you may know.

I've changed the thermostat, the hoses, and flushed out the radiator recently. Now I'm having concerns about the water pump since it's been a while. So far no signs of leaking, overheating, or funny noises.

So, 2 question:

-I heard these things (water pumps) can last anywhere from 50 - 250K. Is there an average for the 280Z?

-I don't have my manual handy right now. Is the pump easily accesible for a roadside repair if necessary? gaskets need?

ps....Just called MSA and was told there are no regular intervals recommended by Nissan. One associate claimed that his lasted about 130K. Anyone else?

[rtaylor]

If it did go out, a water pump is not the type of part that you would want to change on the road, especially if the bolts that hold it to the block snap off in the block. The bolts are prone to rust issues that can't be seen. After mine broke I had to drill it out after breaking an ez out in the block.

Not saying that you need to change it, but the above is what could happen if the water pump did go out.

[Arne]

Not Datsun specific, but since water pumps aren't all that expensive, on my cars I typically replace them any time I'm doing any kind of cooling system repair. Not during coolant change, but if I do a thermostat, or radiator work and everything is already drained, the effort and cost to change it then is minimal.

[JonnyRock]

I just replaced mine two weekends ago. It's the first time it's been replaced, but my engine only has 65k on it. The bearing was obviously going out. Once I got it off, most of the bolts were considerably rusted. And the old gasket was ridiculously difficult to get off.

Let me tell you, it is not something you want to do on the roadside! It is a PITA. You've gotta drain the coolant, and bend over the block for a good while. Yes, there's a gasket. But it usually comes in the box with the pump. Be sure you bring silicone sealant with you if you decide not to change it pre-trip. Unless it's not obviously bad right now, it's not something I think I would worry about right now. Have you had any concerns about cooling recently? Any signs it's been running hot?

[AndysPlit]

I just replaced mine two weekends ago. It's the first time it's been replaced, but my engine only has 65k on it. The bearing was obviously going out. Once I got it off, most of the bolts were considerably rusted. And the old gasket was ridiculously difficult to get off.

Let me tell you, it is not something you want to do on the roadside! It is a PITA. You've gotta drain the coolant, and bend over the block for a good while. Yes, there's a gasket. But it usually comes in the box with the pump. Be sure you bring silicone sealant with you if you decide not to change it pre-trip. Unless it's not obviously bad right now, it's not something I think I would worry about right now. Have you had any concerns about cooling recently? Any signs it's been running hot?

No signs of it running hot whatsoever. As far as I've been concerned it's been "tip-top" in that area. However, that does sound like a P.I.T.A. Is the silocone just for safe measure in case it leaks?

[JonnyRock]

It's needed to properly seal the gasket. I used basic engine "blue" silicone. There are a few different forms, like "high heat," but blue works just as well.

[Arne]

I normally use true gasket sealant instead of silicone. Same reason.

[Nissanman]

I heard these things (water pumps) can last anywhere from 50 - 250K.

Maintenance interval is really dependent on the quality of the coolant that has been used in the engine and the tension of the water pump drive belt.

If for example the edges of the alloy thermostat housing neck are still smooth and corrosion free, then it is reasonable to assume that the water pump is in good condition.

However the bearing may still get a dose of the growls.

If there is no wobble in the water pump and it feels smooth and quiet when rotated by hand, chances are it is still serviceable.

I would advise against using any RTV type sealant.

Use a non-hardening gasket sealant like Permatex.

It is excellent stuff, won't damage your engine and any that squeezes into oil/coolant passages is harmless.

NOT SO with RTV

Also, I advise the use of Nissan Long Life Coolant.

Great stuff, designed for Nissans and relatively cheap:love:

[Beefcakez]

Mine just started to leak.. so this weekend i have to replace it so as for yours.. if you want to do it. then do it... because you will probably end up doing it anyways am I right?

[Walter Moore]

I usually replace water pumps when they start leaking from the weep hole.

I also usually add some stop-leak to the radiator after I replace one, just because it seems like if I don't do it initially I will have to do so later.

Strangely, when I rebuilt the 240Z's engine I didn't need to do that. Perhaps because I had the block cleaned at a machine shop before I rebuilt it.