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View Full Version : Need help with noise from crank!



RAW INC
11-05-2008, 03:12 PM
I really could use anyone's input on trying to figure this problem out. On my 95' SC I can't really describe the noise, sounds like a whistle, or some sort of high pitch noise coming from around the harmonic balancer and crank. I removed all belts and the sound is still present. was just gonna just go ahead and replace the harmonic balancer but what puzzles me is that when i shut the car off, the sound is still present fo about 2-3 seconds like its depressuring. anyone have any ideas?

watsonlk
11-05-2008, 04:13 PM
I have the same thing coming from my car, but it's hard to hear over the voices... :D

If you figure it out, let us know.

KMT
11-05-2008, 04:35 PM
Done any work on it lately?

the-big-e
11-05-2008, 04:38 PM
While the engine is running, pull your dip stick out and put a finger over the tube.....

Are you getting any outward pressure.....:confused:

kevsha
11-05-2008, 05:00 PM
While the engine is running, pull your dip stick out and put a finger over the tube.....

Are you getting any outward pressure.....:confused:

i am, a ton of it:eek:. but i have no whistle from the front of the car???:confused: is it from the bottom of the motor or the top.... does the pitch change with rpm? sould it be described as a squeak, the only thing i could think is maybe a bad cmp sensor?

DrFishbone
11-05-2008, 05:04 PM
Maybe your HB is separated and the outer hub keeps spinning after the motor is shut off.

Is your electric fan running all the time while the engine is running?

the-big-e
11-05-2008, 05:09 PM
i am, a tone of it:eek:. but i have no whistle from the front of the car???:confused: is it from the bottom of the motor or the top.... does the pitch change with rpm? sould it be described as a squeak, the only thing i could think is maybe a bad cmp sensor?

Sounds like you have quite a bit of blow-by.....

What yar is your SC and how many miles are on the motor...

RAW INC
11-05-2008, 05:42 PM
While the engine is running, pull your dip stick out and put a finger over the tube.....

Are you getting any outward pressure.....:confused:

i started her up, and when i removed the dipstick i did hear a hissing sound when i pulled it out

kevsha
11-05-2008, 06:02 PM
Sounds like you have quite a bit of blow-by.....

What yar is your SC and how many miles are on the motor...

i am aware i am getting blowby, i'm not sure what a yar:D is but its a 1990 with 108k miles on it. i only really get it when i start making alot of boost, if i drive around and dont make more than like... 5psi or so its fine.... its when i start going over 15psi that it hapens lol. its fine though, my crank is kept well ventilated :cool::rolleyes::eek: lol

but this topic isn't about my car, lets help out RAW INC

the-big-e
11-05-2008, 06:51 PM
I am having problems with my "e" key.....:rolleyes:

It sure sounds like both of you have blow-by to some degree.....

The 93s seem to be more prone to blow-by for some reason, IMHO....

RAW INC
11-05-2008, 07:11 PM
Thanks Big E, the dipstick got me going in the right direction. lets just say I had sealed my dipstick a tad bit more than the norm. but anyway when the squeal started i would pull up the dipstick to relief the pressure and it stopped instantly, put it back wait for the pressure to build back up and it started again. is this a good thing for having everything seal or was i damaging the motor by having too much, i guess crank case pressure

RAW INC
11-05-2008, 07:25 PM
guess i need to check into a better pcv valve

KMT
11-05-2008, 08:46 PM
>was i damaging the motor by having too much, i guess crank case pressure

Crankcase pressure must have a way to relieve.

Running an engine closed up can create leaks and increase oil consumption, so damage may depend on how long it was stifled and what kind of service the engine saw, along with the overall condition of the engine, miles on it, etc.

the-big-e
11-05-2008, 09:01 PM
I would look into a new PCV valve to help lower the crank case pressures....

I would think that too much pressure could cause a host of problems like blowing the front and rear seals out causing ugly oil leaks....:p

RAW INC
11-05-2008, 11:03 PM
Thanks everybody for your help

fly360
11-07-2008, 02:39 PM
Check your oil filler cap also, IIRC Fords were vented and Chevys were not. If the oil filler cap is pluged it would build up more pressure than the pcv system can handle. Check the compression also to see if it is not the rings.