MichaelR

Hi, folks. Question about my 85/auto. I've just noticed, over the last week or so, a strange rattling/clanking sound from the front of the engine. It's RPM related, and gets better as the engine warms, till it's hard to notice at all.

At first I thought it was coming from the air pump, and as it warmed up perhaps the change in the belt made the noise stop. However, today I've removed the fan, shroud, and air pump belt. Noise still there. Seems to be coming from closer to the top of the engine, rather than down low by air pump. A little left of center, too.

Checking with the stethoscope didn't help pinpoint it too much, other than the general vicinity. Left cover is off, belt looks good, and tension is good (Kempf tool). Does the area and description sound like a water pump on the way out? I've never "heard" a water pump fail, just had them start leaking. As I said, the noise is somewhere between rattling and clanking, almost diesel-esque, perhaps.

I'm thinking seriously about rolling the car back into the garage until I can get a water pump to replace it with. Don't want that thing to sieze. Any suggestions on a way to make sure it's the pump? Or another theory?

Thanks for any advice...

Randy V

When was the water pump last replaced Michael?

They typically last 2-4 years, depending on how much you drive the car.

If you have the pump type with the metal impeller (instead of plastic), a pump bearing failure could cause damage to the block (so I've heard).

MichaelR

Belt and pump were done June '01, so it's not quite 1.5 years yet. Seems a little premature to me.

MichaelR

Anybody got any BTDT experiences with noisy water pumps...or other related noises? Still want to pin this down a little more before replacing it, then finding out that wasn't it!

Incendier

Dunno if this is the same, but see my recent post "Bullet Dodging" for what happened to me after my water pump was making the same sporatic noise at startup.

You don't want to see my garage about now...or the grenaded water pump that came out. Drive at your own risk...

Thom1

Hi Michael,

Let me call anything such as a roller or idler with bearings in it a bearing. For a BTDT, see my TT (Torque Tube) write-up excerpt below. With the stethoscope, the air pump seemed noisiest. I also found noise in every accessory, and the water pump, e.g., every such device with bearings driven by a belt. Wherever there was a bearing, there was a noise. It turns out that the TT bearings and TC (Torque Converter) bearings were bad. I imagine that the stethoscope would have revealed those bearing failures with tremendous racket had I put it up on a lift. Instead, my mechanic with a lift found the culprits. One of the bearings in the TT was half on the shaft, half a few inches down the tube. Brad theorized that the TC bearings failed as a result of the TT bearing failure. I really heard the RPM dependant noise inside the car. It wasn’t coming from the engine compartment.

There are also other bearings that interface with the timing belt. Since the front timing belt cover is isolated from the timing belt bearings, I don’t know if the stethoscope applied to that cover will provide a definitive diagnosis. But, you may be able to get the stethoscope in there, and find louder noises. Those bearings bolt to the block.

TO DIAGNOSE TORQUE TUBE (TT) BEARING FAILURE:
Just when I thought I had it about right mechanically… that new noise has been diagnosed as torque tube bearings… kinda’ like a grrr… rpm dependant… more obvious noise inside the car, than when listening under the hood. To identify source, use automotive stethoscope, or long screwdriver (press ear closed with screwdriver handle, and hold tip to suspected noise source). Put car on lift. Hear more intense noise along the TT area.

Let us know what you find.
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John.

I've seen pumps make moise before leaking. It is possible. Is it possible it was low quality rebuilt unit? There are a lot of them out there. If you do it over, make sure to get the rebuilt unit with the plastic impeller, as the cast one can work its way straight into the block if there is major bearing failure.

MichaelR

Thanks for the advice, guys. Looks like I'm gonna learn how to do a water pump replacement!

PorKen

I too have had a nasty clack/grinding noise, especially when cold, and feared it was the water pump.

(I noticed it the day after a short 138MPH run )

Finally this morning I did as my old timer neighbor had suggested and rubbed a soap bar on the belts as the engine was running (carefully).

Sure enough, it was a loose power steering belt!

Kind of like those Capitol One commercials, I saw the approaching dollar signs running away...

MichaelR

Thanks for the tip! Can't hurt to try...unless I get appendages caught in the fan, that is. I know the alt belt is OK, but can't remember checking the PS belt too closely. Worth another look.