diagnose screech

[1969c10joe]

I have a screech when i rev engine it happens in neutral and in gear only in second my first gear is granny. it is not a belt squeal. clutch fan seems a little tight but its doesnt sound like an airplane. also throttle response seems to lag a bit it only does it when rpm is low and i give it the gas hard.I wouldnt worry but i hope to motor across country and i know a sticky clutch fan robs power lowers mpg

[geezer#99]

It's your fan belt!

[davepl]

...or power steering. But it sure sounds like a belt. Why do you say "It is not a belt squeal"?

[Stocker]

x2 -- why do you say "It is not a belt squeal"?

I'm very curious what the problem is because my K20 has recently developed a similar noise, usually around 1400 rpm. Doesn't always happen and I've been unable to duplicate it in my driveway. I tried soap on the belts -- adjusted the belts -- finally changed the belts. Still have the noise. I hope it's not the water pump, but I hope I find/fix it before changing coolant.

A thought on that fan clutch, if you think it's going bad. Inspect it closely for any hint of fluid leakage. Pay particular attention to the back of the unit, where the shaft joins the clutch. That seal might be leaking, and it's kinda hard to see, which makes it easy to miss. Doesn't take a lot of leakage to begin drying out inside.

[geezer#99]

Try some belt dressing Stocker.
https://www.walmart.com/ip/Prestone-...ssing/16817510

[1969c10joe]

Originally Posted by geezer#99

Try some belt dressing Stocker.
https://www.walmart.com/ip/Prestone-...ssing/16817510

low on cash would prefer to spend money on a new belt would that be an acceptable idea sir?

[geezer#99]

Originally Posted by 1969c10joe

low on cash would prefer to spend money on a new belt would that be an acceptable idea sir?

Yes!
If you need one!
How deep does the current one there sit in the groove?

[Stocker]

Originally Posted by geezer#99

Try some belt dressing Stocker.
https://www.walmart.com/ip/Prestone-...ssing/16817510

Thanks, but no. I tried it years ago and all it did was make a mess. I've had good luck verifying bad belts (or adjustment) by rubbing a bar of soap against the belt with the engine idling. Obviously anyone trying this needs to keep clothing & body parts safely away from moving belts / fans / pulleys!

Anyway I have already changed the belts which suggests there's no belt problem.

[1969c10joe]

thankyou both for quick reply it sounds different more like metal to metal bearing screech and fan seems a little tight i have adjusted belt and no change im thinking bearing maybe alt. but i kind of think its fan clutch just wanted expert opinion ill change out belt to help diagnose n keep it for spare if you advise

[davepl]

Well if its not the belt, then that'd leave you with water pump bearing or power steering pump, I think.

[1969c10joe]

only have one belt i installed good wrench engine with new water pump kept alt. and clutch fan and it did it before engine install thanks again you guys are amazing all of you

[geezer#99]

Likely you have the wrong belt.
How deep does your belt sit in the pulley grooves?

[1969c10joe]

Originally Posted by geezer#99

Likely you have the wrong belt.
How deep does your belt sit in the pulley grooves?

good idea my belt sits flush ps i have a motor neuron disease and with this touch screen phone itakes me forever to type response that isnt mispelled not complaining

[1969c10joe]

Originally Posted by 1969c10joe

good idea my belt sits flush ps i have a motor neuron disease and with this touch screen phone itakes me forever to type response that isnt mispelled not complaining

im sooruy meed break hsnds twitching too much now yhankyou im still teading rrdpondrd responsrd dam phine

[1969c10joe]

how freely should fan spin when engine is off and cold its kind of tight it does not free wheel. the shaft does look a little oil on it very minor

[Stocker]

Originally Posted by 1969c10joe

how freely should fan spin when engine is off and cold its kind of tight it does not free wheel. the shaft does look a little oil on it very minor

Hard to describe but I think of it as gooey like it's mired in molasses. It should not spin freely, and should stop as soon as you release it. No freewheeling. Yours sounds normal to me.

[1969c10joe]

current belt sits flush hope i describe this correctly the belt does not stick out above pulleys and the contour matches pulley it had wrong belt when i got it and i had the guy at auto parts store come out and look belt is two years old has mmm 10k miles on it I will buy belt and change and keep old one as i have spare carb. distrbutor hoses gaskets carb rebuildkit etc nothing wrong with extra fan belt

[Stocker]

Originally Posted by 1969c10joe

current belt sits flush hope i describe this correctly the belt does not stick out above pulleys and the contour matches pulley it had wrong belt when i got it and i had the guy at auto parts store come out and look belt is two years old has mmm 10k miles on it I will buy belt and change and keep old one as i have spare carb. distrbutor hoses gaskets carb rebuildkit etc nothing wrong with extra fan belt

Good description! One other thought -- do the pulleys line up? If not, that could cause a squeal (and shortened belt life).

[1969c10joe]

yes pulleys line up

[geezer#99]

One last thing to check.
Unplug the voltage regulator and test again.
If no squeek then it's your altenator charging strongly that puts an extra load on the belt making it slip.

[1969c10joe]

Originally Posted by geezer#99

One last thing to check.
Unplug the voltage regulator and test again.
If no squeek then it's your altenator charging strongly that puts an extra load on the belt making it slip.

i thought that unplugging reg would causr alt to run wide open?

[1969c10joe]

sometimrs i run out of patience i do know how to spell.Anything wring with removinh fan clutvh and starting engine . I only have to ruun it for a moment just thooughht of that

[davepl]

You can run it without the fan for a a minute, sure (or less). But make sure the pulley is still bolted on. Don't just remove the fan and bolts! Anything's possible, but it seems like low odds it'd be the clutch making noise.

[1969c10joe]

Originally Posted by davepl

You can run it without the fan for a a minute, sure (or less). But make sure the pulley is still bolted on. Don't just remove the fan and bolts! Anything's possible, but it seems like low odds it'd be the clutch making noise.

i agree odds are low i will leave pulley on replace belyt if noise persists its alt right?

[1969c10joe]

Originally Posted by davepl

You can run it without the fan for a a minute, sure (or less). But make sure the pulley is still bolted on. Don't just remove the fan and bolts! Anything's possible, but it seems like low odds it'd be the clutch making noise.

i will leavr pulley on install new belt if noise persists then its alt?i agree unlikely clutch fan thanks dave