JonnyC

iTrader: (19)

So I finished my install a few weeks ago. I have the stock bypass valve, and originally had it set to 6-7 threads. Everything sounds great until I get up to operating temp. On decel, I hear a fluttering like squeal coming from the blower. It can be heard with the windows up and down, but isn't loud enough to be caught on video (at least with my digi cam). It seems like a metal on metal noise (like brake noise), but isn't the normal gear noise, and is pretty faint. It goes away after idling for a little while, but will come back on decel again and stick around for 5 seconds or so.

It might be my imagination, but it seems as though the bypass valve isn't as loud at this point (decel and idle), so I'm thinking it could be compressor surge (bypass valve isn't opening as much after it gets warm?). I am seeing 20+ in. of vacuum the whole time though. So I adjusted the bypass valve so the threaded bolt is almost all of the way out (8+ threads), so it barely applying any extra pressure to the spring. Went for a spin, and everything seemed better, until things got hot again. It's hard to diagnose too, since by the time I get out of the car and pop the hood, it will have gone away.

I'm going to try to take apart the BPV Saturday to make sure everything is intact, and then adjust it so absolutely no pressure is on the internal spring.

Any clues? Anyone experience this? Thanks

- Jon

jpc350z

Symptoms sounds like BPV not opening properly to vent compressed air downside of blower..

booger

iTrader: (6)

Put it to 9 threads showing and check your vacuum hoses . Then see if it does it

JonnyC

iTrader: (19)

Alright, I'll do that tomorrow and see what happens.

JonnyC

iTrader: (19)

Alright...adjusted to 9 threads, it's not even pushing on the spring at all, and I still have the issue. I can tell that the valve is open, so I'm thinking it's not compressor surge anymore.

This video really accentuates it...but this is just after pulling in from some driving..

http://www.youtube.com/watch?v=_LJcPO-8I9Q

And this is pulling in the garage right after the last video - noise is very faint...but pretty much gone. Like I said before the noise doesn't start until after the engine has fully warmed up, and goes away after idling for 10 secs or so and doesn't return when revving - only after doing some driving.

http://www.youtube.com/watch?v=Mh2_35eKvhc

I need to pull the filter off (if I can) and make sure the impeller blades aren't tearing up the housing :-/

Sigh...

JET MECH

iTrader: (2)

i would definately pull the air cleaner and check for compressor rubbing and shaft end play to rule that out first. i have never had a BPV make that noise. if any thing i have had compressor surge before on my vortech but it sounds just like a turbo "squelch" in between hard shifts.

JCstart

iTrader: (6)

WOW ! same sound when I jacked the Vortech bearing... but, it was getting worse when hot...

first, spray some silicone on you cog belt... mind, produce a strange noise when it's wet... just in case...if you are lucky...

JonnyC

iTrader: (19)

Well phew - the impeller blades and housing look good. However, on removing the filter I noticed a nice strand of wire from the filter dangling in there (thanks Vortech)...

bad picture - was like a 3 inch long strand of wire.


This no doubt probably got eaten up a bit by the blower, but that's not what was causing this sound. I took the cog belt off and spun the blower and didn't notice anything strange.

I pushed the car real hard today since we had two cruises, and I needed to keep up The noise is no doubt still there after running it while its hot. After coming home I noticed that the bolt holding the 3.33 pulley on was loose - like I could loosen it with my fingers . So I tightened that up hoping that was it, but I still have the issue.

I'm thinking it's a belt or pulley issue maybe? By the time I get under the hood the noise goes away, and I can't rev it myself. I had my friend rev it for me, but the noise goes away too fast after pushing it. Sometime this week I'll have him ride with me so I can hop out right away after running it hard and he can rev it.

jpc350z

Sounds like bearing noise.

JonnyC

iTrader: (19)

Yeah, that's what I'm afraid of. Quamen said that maybe the way I have my oil feed line hooked up could be causing the issue. I have it coming out of a sandwich plate, so i don't see how it could be any different. However, I need to make sure there isn't any blockage in the oil nozzle. I have noticed that the blower gets hot as hell though...like I just have to tap it otherwise I'll burn the crap out of my hand. But it's really no different than the rest of the motor.

jpc350z

I find my blower toooo hot to touch also..Not sure that's indicative of a problem although cooler is better than hotter.. Wonder what others are experiencing on blower temp..

JonnyC

iTrader: (19)

Alright, so Quamen pointed out that this might be an issue with a pulley somewhere - jackshaft, a/c, or power steering. The noise would be much more frequent if it was the blower, at least we think. I'm going to check the tension on the a/c and try turning the a/c on and off when the noise is there and see what happens.

350Z400rwhp

iTrader: (4)

Hey Johnny I noticed on your build pics that it seems like two of the pulleys are missing from your supercharger bracket. Maybe I'm just looking at it wrong but just wanted to throw that out there.

JonnyC

iTrader: (19)

That's just the revised pulley setup In the Vortech FAQ thread it shows the different setups.

350Z400rwhp

iTrader: (4)

Figured it was something like that. Damm I was hoping to be the hero here

JonnyC

iTrader: (19)

Hahah, sorry :-/ I'll play around with things tomorrow and post up what I find out.

JonnyC

iTrader: (19)

PHEW! Alright, I should have tried a few things before posting this thread. I removed the cog pulley, disconnected the BPV and drove around - no squeal. So I looked at the belt and one edge was worn down to the metal. I realized the cog idler pulley might need to be flipped around, since the belt was on the very edge for the blower cog pulley, and the edge of the idler pulley that the belt always touches was a little beat up. So I flipped the belt around (where the metal wasn't exposed yet), and flipped the idler pulley around so that the belt rests against the non beat up edge, and sits in the very middle of the blower pulley.

So...no more sound Thanks guys for the help!! I can't wait to get this thing tuned for power now!

jksstar

iTrader: (7)

glad you got it man. Make sure you post up some #s after you get it tuned