Power Steering Whistle

[john keefe]

Can't seem to isolate this noise. It's a very loud whistle that seems to be coming from the PS pump when cold, and now sometimes after warmup. Loud enough that I want to shut it off for being annoying to the neighbors. Not the usual PS whining or chuckle. It would seem like a massive vacuum leak, but haven't found any, and the engine runs fine (just rough while warming up).

Spraying belt dressing only causes a loud racket, like the PS pulleys are out of alignment; like the spray creates friction between belts and pulleys which "grabs" the pulleys and causes bearing chuckle.

I've noticed on ocassion that the whistle will cut out after the auto shifts. But, can't find an air leak. Aren't these Saginaw pumps? Is this something peculiar to that brand? The only reference I can find on-line to whistling is with the GMC Saginaw pumps...

[Ed Lijewski]

No idea what the cause is, but try a bottle of LubeGard power steering additive. Company tech recommends it to shush Ford pump whines.

YMMVZ

[john keefe]

Thanks Ed. Used that when I flushed the 5.0L pump a couple weeks ago (not a whole bottle, though, only holds about 1.5qts.). I suspect this is a Saginaw pump, like GM... should work, right? Also, any idea about why I'd get such a racket when spraying belt dressing? The belts are snug. I'm thinking something's up with either the PS bearing, or somehow the pulley shaft got misaligned.

ps. just cross-referenced, and that pump fits all sorts of GM products in that era, and a couple of Jeeps. Remans are relatively inexpensive, but I'd rather solve this the old fashioned way, rather than throwing parts at it.

Anyone tried to shim the pump on the bracket to align the pulleys better with the water pump pulley? Thinking that would take an awfully thin washer.

[Ed Lijewski]

I'd loosen the belt and rotate the pump pulley manually to see if you feel heavy resistance or bearing rumble.

Just replacing the pump strikes me as reasonable. No idea how many miles on yours but my '89 with only ~85K on it when I got it was leaking (one reason the owner decided to let it go-it was his wife's car but she had passed). I had a spare used one with ~100K on it that I installed which is working fine, no leak or bearing noise).

The pump on my '88 is original with 150K and no leak or bearing noise.

The belts/pulleys on each car run true.

Your pump may be "prematurely" dying. It happens.

YMMV

[john keefe]

Seal kit, or whole new pump unit?

[Ed Lijewski]

I always try to cheap out where I can, but for just under $50 shipped for a reman unit on Rock Auto I'd go that route. Especially since your pump seems to be generating a noise rather than leaking.

But noises under the hood can be deceiving re their sources. Use your engine stethoscope (I bet you have one) to see if it is coming from the pump.

YMMV

[brokencase]

Also - watch out for deteriorated power steering hoses and/or clogged power steering rack.

If you put the new pump on and it still makes noise then you have issues elsewhere.

Also suggest you put a power steering filter on the return line back to the pump reservoir.
https://www.autozone.com/filters-and-pc ... /13909_0_0

[john keefe]

Thanks for the info, guys. Will hopefully have some time in the next few days to look at it, probably get a rebuilt/reman.

[andyofcolumbusmerkur]

I've heard those high pitched noises before, usually a tensioner or idler pulley. Shoot a small amount of oil on them and see if the sound changes.