Trivia Q: What's the REAL reason for the weep hole on water pump snouts?

On the web, Automobile Water Pumps Weep Holes cuhulin

Reply to
cuhulin
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Why would you need to protect the bearing on a bad water pump?!?!

Reply to
twisted

twisted wrote in news:5bbd38e9-dfab-430b-8b64- snipped-for-privacy@a6g2000yqm.googlegroups.com:

Probably because a bearing that becomes contaminated with coolant will probably seize up solid really quickly. Most, if not all, belt-driven Hondas have water pumps that are driven by the timing belt, so water pump seizure would be a disaster.

Reply to
Tegger

The pump may be run a long time with the seal that is "weeping" a little.

The reason for the weep hole is to mostly protect the bearing. This is pretty standard design for any horizontal centrigugal pump. There is usually not much space between the bearing and the seal so even a tiny amount of leakage would fill up the space and threaten the bearing (the bearing usually has its own seal but not one that is designed to keep hot coolant under pressure out). If the pump is driven by a belt the weep hole is protecting the bearing. If the pump is driven off a shaft from inside the engine the weep hole is also protecting all the engine internals from getting contaminated with antifreeze.

-jim

Reply to
jim

Makes sense.

Reply to
twisted

Until you realize that the weep hole is between the bearings. For the coolant to weep out, it must pass thru one bearing.

Reply to
Steve Austin

Seems like those weep holes are a mystery, to some people anyway. I still find ''them'' a mystery.

Oooooops,,,, cuhulin

Reply to
cuhulin

Every bearing i have seen is a single bearing with a double row of bearings. the outer race is solid. There is no way water can get out between the bearings.

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Reply to
jim

jim wrote in news:h5idnSZGU60N18fWnZ2dnUVZ snipped-for-privacy@bright.net:

Going from memory here 'cause this is nothing I ever thought to study with a microscope... but all the OEM Honda water pumps I've seen appear to have a single, wide roller bearing. The bearing is contained within the snout, which is itself buried inside the hollow, cogged pulley that engages the timing belt. The seal is inboard of that, and the weep hole is between the two. So...

Reply to
Tegger

The bearing looks like a single long bearing but it is really the equivalent of two ball bearings side by side. At least that's the way most car engines are configured. Heavy duty engines usually have tapered roller bearings more like car front spindle bearing. No matter how the bearing is designed the weep hole is put there to allow any coolant that gets by the seal to drain, instead of getting into the bearing.

The weep hole is the end of a passage that can come out anywhere on the bottom of the the pump casing (depending on where they want the water to drip). The hole may look like it comes out from the front or middle of the bearing, but the passageway originates from the gap between the bearing and the seal.

-jim

Reply to
jim

Do you want to be able to drive it home, adding coolant as needed... or do you want it to seize up solid and strand you 130 miles from the nearest town in the Nevada desert on a sunday afternoon?

Reply to
Steve

You forgot the part about locking up and tearing the timing belt causing the engine to destroy itself, on those engines where the timing belt drives the water pump. (Yes, I think that's a stupid idea too.)

--scott

Reply to
Scott Dorsey

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