wierd screeching noise

92redsc

Registered User
my car was finally running good after a head gaskets and gutted cats, and then something happened and i cant explain it very well.
Here it goes. i drove about 100 miles good after everything. all of the sudden it started making a screeching sound under WOT. kind of wierd high sound. it started doing it more and more and then i relized i was having to floor it to keep my speed up with the boost gauge all the way to 6 psi in 5th gear, and it was hesitating. this was on a 70 mph highway and i was losing speed and my engine was screaming at me (with that sound). i shut it down and pulled the car home. i cant figure out what is wrong. i thought it was a pulley. nope it isnt. i checked the supercharger fluid and it is a little low. im going to fill it up and see if it helps but????? any ideas?
 
If SC fluid is low it's probably leaking out the front seal and getting SC fluid on the pulley. With the engine OFF, feel under the SC snout and see if there is black oily film under there. Sounds to me like you just have SC belt slipping under power. Might want to also check the SC tensioner for full travel and tension.
 
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i know the fluid came out when we were putting the HGs in because it was tilted to the front on the ground. it leaked very little in a 3 weeks period, but enough to make it go down a little. is it not supposed to leak even when its tilted to the front? if not how do i fix the leak and how much will it cost? the tension is ok as well as the pulley itself. i dont know why its making this wierd sound. i have some more fluid and i will put it in and see if it helps at all. i am stumped. i was getting boost so i know the belt wasnt locked up. help guys thanks.
 
i do have a small leak at the front of the blower but it is now full and the car is still making the sound. the belts are good. i took off the pulley (the one on the 8 rib belt) just to check it, and it makes some noise like a ratcheting sound when you spin it.a real fast ratcheting sound. mabey at 750 rpms it makes that screeching noise? the car is running fine with the fluid in it but, its still making that sound. also 1 more question, when u shut the car off, are you supposed to be able to hear the boost bleed off?
 
i started it up again and it actually ran good for a sec, but it was still making that noise. i turned it off and tried to restart it and it wouldnt start. if you gave it gas it would, but then it would stumble and die, all while making that noise. it kind of changed from a high piched scream, to that and a knocking noise. sounds like from the blower. the more i try and listen, the more i think the sound is from the blower. can a blower go bad? do i have to get it rebuilt or what? i didnt know the fluid was low because it was full when we pulled it from the engine, but, as i said, it leaked out some, probly 3 oz. and thats when this happened. will running it a little low cause this? i filled it back up using 3/4 of a 4 oz. bottle so it lost about 3 oz. help please, as i have to drive the old 85 ford 2 tone truck that gets 5 mpg.
 
If you have a sound like that that when you turn your pully it sounds like a bad bearing in the SC nose. I can relate, I pulled mine off and had it on the bench at a downward tilt and the whole garage smelled like crap the next day from the couple of ounces that leaked out. I am not as far asd you though as far as completing the rebuild of the engine to test run everything. I bought BP turbo oil for the SC.
 
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You can pull the SC belt and try starting it. See if it's still noisy. If yes it's not the SC.
 
i tried that and it wont start without the blower belt on. Is it supposed to? if it wont is it somthing else?
 
Hey, let me know where you are, and I will come help; I won't bring my car though( you would be jealous that it runs good):D J/K
Let me know if you want my help:cool:
 
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