engine and drivetrain Screaching noise

[bigboysurf]

Just picked up a 1972 2002, descent body, tired engine.

Blows blue smoke when leaving a stop, smokes on long deceleration

(going down hill), smells like burnt oil inside car. guessing valve guides gone

from the deceleration issue, but are the rings maybe going too? Blow by?

Compression #1 150, #2 135, #3 140, #4 130.

Engine still pulls well.

Other problem, car screaches when rolling, when first start driving. Accelerate up, noise starts

push clutch in same, neutral same, slow down noise slows down, in gear or neutral, will just

stop and pick up again mostly when cold, but sometimes when hot. engine running or not.

Not wheel bearing, not consistant. Sometime hardly make any noise, others, well a lot.

Ideas?

[Drosselhebel]

Screech could be v-belt, alternator, water pump, or something driveline or brake related. Your description would rule out release bearing noise, but could be pilot bearing. To start with try spraying the v-belt with silicone lube while running, and check weep hole on the underside of the water pump for dribbles. Wiggle the water pump pulley with the engine off; any play is abnormal. If you can induce the sound at idle, check alternator body with a stethoscope or long screwdiver held to your ear (not on the B+ terminal of course.) Make sure v-belt is not loose, it should have about 10mm deflection (check alternator bushes and alt ground strap too.)

 

Regarding smoke, yes, the majority is probably guides and seals. Have you adjusted the valves? Valve adjustment does have an impact on compression readings; make sure the clearances are right before assuming rings are bad. A leakdown test is more telling than a compression test.

[bigboysurf]

Will adjust valves and see what happens.

Forgot to mention the screech, is definitely not the vbelts, that is the first thing I looked at,

and if I shut engine down while rolling, the noise persists, in relationship to speed,

ie; slows down as car slows, and stops before car stops rolling.

[Mike87]

As far as your screeching, check your center bearing on the drive shaft. I have had one screech before, but not constantly. Mine was only at about 35 MPH. Just changing the preload on it might help.

['76mintgrün'02]

Front brakes?

Any dragging?

How are the pads?

[ray_]

What Mike said.

 

Cheers,

[Hans]

can you determine if its coming from front or back? maybe backing plate scraping? Hard to imagine centre bearing screeching. What happens when you touch the brake pedal? Or turn the steering wheel from side to side.

[bigboysurf]

I am going to take the car out today and get more details on when it happens and the circumstances.

The last time I drove it the screeching doesn't change applying the brakes or not, doesn't feel like there is any dragging,

sounds like noise comes between engine and trans, but hard to pinpoint from inside. Screeching is inconsistent.

I will post more details after the drive. Thanks for all the help everybody.

[bigboysurf]

I took the car out this afternoon these are the results:

start car drive out on road, screeching slowly builds, put

car in neutral, coasting on slight down hill grade, shut engine off

screeching continues in varying degrees of pitch but slows as car slows

and ends before car comes to complete stop. Drove it a few miles noise

mostly disappears, little chirps here and there but not like when the car

is cold. Mike87 idea sounds like a good place to start, I'll have a look

at it this weekend when I can get the car up in the air. Any other ideas

while I have the car up would be appreciated....Thanks.

[ray_]

Take your trusty can of WD-40 or similar, and douse the center bearing well. Drive again.

 

That's how I Isolated my issue, without crawling under

 

Cheers,

[jrhone]

Is it a screech or a grinding, scraping sound?  My rear wheel bearings are going and they are making some interesting noises.  Its intermittent and speed dependent.

[bigboysurf]

Wheel bearings as far as I know usually make more of a humming noise that increases when load is applied as in turning.

This is a screech and not so much of a whine though now that I think about it, it sounds a little bit like one at higher pitches.

It almost sounds like a road racing gear box whine almost like shifting down a Muncie M-22, but the noise is all over the place,

and mostly when the car is warming up, but it sometimes happens when the car is at normal running temperature.

[tzei]

Is there oil in tranny? Has it been stationary for a long time? I had the same symptoms with 2002L -75 that had been standing many years. I quess gears/bearings where seized/rusted a tad.

[bigboysurf]

Will check when I have the car up this weekend, thanks.

[roadhog0]

Brakes down to the squealers? Or a rock jammed in there somewhere? Had that happen on an Altima, took me forever to figure out the problem....