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Water pump lube: yes or no?

I have a '99 Honda CR-V, bought last year with 60k on it. Previous owner had just replaced the timing belt, but not the water pump. If the water pump ever freezes, it will break the timing belt and wreck the interference engine. I will have the pump replaced next time I have the timing belt done at 120k or so, but the current pump is already 11 years old and I’m worried about it freezing up before then. I’ve read some people recommending “Zerex water pump lubrication,” but I’ve read other people saying that the bearings are sealed and don’t need lube. Who’s right? I’m tempted to go ahead and add some of this stuff regardless, on the grounds that it probably can’t hurt, and the stuff costs only $3 for a bottle. Plus it contains mostly salts (sodium nitrate) for corrosion protection, so even if it doesn’t help the pump at all, it should do something useful inside the radiator. Let the debate begin.

I wouldn’t worry about it. I believe your OEM Honda water pump will make it well beyond 120,000 miles without any help. Mine made it to 180,000 miles before I had it changed, and it was still working just fine.

Well, my experience with water pumps is that they fail by leaking (caused by worn bearings taking out the seal), or (rarely) by impellers fragmenting, I haven’t had one freeze. So I’d skip it, but that’s me.

Heh. Funny to see that name pop up here. They make a lubricant additive for water-cooled computers too. It’s not a bad product in that unlike some of the others it won’t do any damage. But it’s not really necessary either.

You’re right in that the bearings are sealed. This stuff supposedly lubricates the bearing seal. But the bearing seal isn’t going to dry out anyway, so why bother?

Update: I just called the Valvoline tech support hotline (they own the Zerex label) and asked the guy about “Zerex water pump lubricant and protector” and whether or not it does lubricate the pump bearings. He said the Zerex stuff extends pump life by reducing corrosion on the impeller, which he said is more important because the impeller is spinning faster than the bearings, and when pumps freeze up, it’s due to impeller corrosion, not bearing failure.

Thanks, that makes me feel better…

If your Honda has the correct mixture and is’nt too old, the coolant already has all the lubricant it needs.

BS. The impeller isn’t going to corrode unless you use the wrong antifreeze. If you use the wrong antifreeze, Zerex won’t help you.

He said the Zerex stuff extends pump life by reducing corrosion on the impeller…

What he failed to tell you is that your coolant already contains a corrosion inhibitor. The corrosion inhibitor in your coolant will do that on its own, as long as you use the right coolant and get it changed on time. I get my coolant changed every two years or so.

‘corrosion on the impeller’…wow, that’s a new one! I’ve never seen that. Had he said corrosion in the engine or radiator, at least he’d have a little credibility. Not now…

I’ve seen the fins corroded all the way off of the impeller. It does happen. Of course, that doesn’t cause the water pump to freeze up normally. It just stops pumping.

Don’t. You don’t know how those added salts will affect the insides of your cooling system.

If you want to prolong the life of your water pump, the best thing you can do for it is to drain the cooling system now and again every two or three years and replenish it with fresh coolant that meets the Honda specs for that vehicle. You can flush it out with hose water when you do this, but I recommend against the use of chemical flushes. Then when you hit 120,000 you can replace the water pump and continue the periodic system purging.

Different coolants take different approaches to providing protecting. Typically they use either silicates to coat the system’s insides or chemicals to cause an oxide layer to form, protecting the insides like the oxide layer on the Statuer of Liberty. Some use both. Whatever Honda recommends is the only correct mix, and chenging the chemistry can do no good, only harm.

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Thanks to everyone for weighing in. Based on your collective wisdom, I’ll forget the Zerex, and just continue to change coolant every 2 years using Honda coolant. Sounds like the water pump should be fine until the next timing belt change.

I’ve also seen the impeller completely corrode away on one of my cars. Of course, I never changed the antifreeze.

By the way, since we’re talking coolant chemistry, I found an interesting and informative article on the subject at the Gates rubber company website:

Thanks a million. That’s probably the best article on coolants that I’ve sene yet. I printed a copy for my home files, for when I get old and cannot remember this stuff anymore…what were we discussing again?

I don’t remember either…but since we’ve forgotten, I learned another interesting thing on the Gates site…for my CR-V, they make a “racing” timing belt, as well as the “regular” belt. The “racing” belt is advertised as 3x stronger than the “regular” belt, which makes me wonder if I should install the “racing” belt next time and see how much extra mileage I can get out of it…for a $50 premium over the “regular” belt, if I could get an extra 50k miles out of it, that sure would be worth the investment. May be time to start a new thread on the subject…

The only way you’ll know is by running it until it breaks…something I definitely do not recommend.

My guess is that the “racing” belt you saw has higher tensile strength to handle the larger loads inherant in higher horsepower applications, but contains the same elastomers and will break down just as quickly as a regular belt.