[Glaucus]

Greetings Supra fans!

For months now my car has been emitting this whirring sound from the front end of my '83 P-Type. It's not the normal chirping you get from loose belts, I've heard that before and it doesn't sound anything like that. This is a constant, high-pitched whirling sound - the sort of sound you'd expect from a piece of metal rubbing up against a rotating rod or pulley. The sound starts up as the car warms up and the idle starts to go down. Once it hits 1000RPMs the sound gets loudest. If the RPMs drop below 1000 the sound seems to get a little fainter but doesn't go away (btw, my idle RPMs seem to be around 900, is that too high?). I can't hear it when driving but it's possible other engine/road noises mask it.

What I'm not sure about is where it's comming from. Now, the A/C compressor has been removed so I know it's not the problem. This leaves the alternator, power steering and possibly the water pump. Which of these would be the most likely source of such a sound? Do alternators make this sort of noise before they die? Aside from this noise the car runs great, no problems at all, but I'd really like to know where this sound is comming from and if it's an indicator of any near-future break downs. Norally I wouldn't care but I'm planning to drive out to the West coast (about 2500km from here) and I'd like some peace of mind. Any thoughts? Any tests I should perform to narrow it down?

- Mike

 

[Glaucus]

Thanks for the replies guys, I am leaning towards the water pump as the possible problem as well. I have a spare water pump taken from an '85 5MG-E, will that fit? I've never installed a water pump before, does it require a special gasket or anything else? Don't want to take it off to realize I'll need to make a trip to a dealer before I can put it all back together again!

For things driven by the fanbelts, you can remove the fanbelts one at a time until the noise goes away.

I thought of that but was worried about running the car without the alternator functioning. Don't want a dead battery on my hands.

- Mike

 

[Glaucus]

Btw, is there a good way to test if the water pump is function well without taking it off? The car did overheat once when I took it on the high-way about a week ago, but since then I flushed the rad out (3 times) and changed the t-stat. I had since taken it on the highway again at high speeds on a hot day and the temp was normal the whole time. It seems that the cooling system works.

I did however pinch the top rad hose and I didn't notice any real strong pressure inside. How much pressure should I expect from simply pinching the top rad hose?

- Mike

 

[Glaucus]

If your water pump turns out to be the culprit, you'll need a new OE water pump and gasket.

Do you mean to say that installing the spare '85 water pump I pulled off my buddy's parts car is not a good idea?

- Mike

 

[Glaucus]

Okay, well I'll remove the belts one at a time tomorrow morning to see if I can isolate the problem (I'm also considering using my sister's stethoscope - she's an MD ;-) - to pin point the source).

If it turns out to be the water pump I might just go ahead and replace it. Today I noticed some grinding noises, the sorta sound you'd expect from bad bearings. Since I'm considering driving this out to Vancouver later this week (about 5000km round trip) I should get it patched up now and avoid any headaches later on.

 

[Glaucus]

Okay, well, using the process of elimination I concluded that it's not the water pump at all but the alternator! So I have one on order and should be installing it some time later today or tomorrow morning. The water pump on the other hand seems to be rock solid. After I took the belts off I tried to wiggle the pump's pulley and it was solid with no movement. I spun all the pulleys with my hand just to see how freely they spun and again the water pump's pulley spun without a problem and was totally silent. The alt. on the other hand was un-even and noisy. In fact the whirring sound only happens when the alt belt was installed.

Also, to completely exclude the water pump as the source I hooked up one of the alt. belts to just the water pump pulley, by-passing the alt. pulley completely. With this set up, aside from some belt slippage, I could not hear the whirring sound at all. This tells me it's the alt. So that's that. Thanks for the suggestions everyone!

- Mike