Background on car- 89k miles, custom intake,custom exhaust and stock exhaust manifold.

My craven pulley showed up yesterday so I decided to install it. Install went smoothly using the craven pulley puller. now when free revving it sounds almost like gears grinding. But ONLY when free revving. Under load while driving it doesn't do it unless I rev match while down shifting ( free rev) another symptom I have is the boost...I used to make about 11-11.5 lbs before the pulley install. But now its at 10.5. Its gets there alot quicker than the old pulley but im not sure why its not boosting any more than this.

I appreciate any help or ideas

Ps I treaded a bolt into the sc input shaft and snugged it down and marked it along with the pulley to see if it was slipping, and that doesn't seem to be the case. I also nstalled a new belt.

 

and now this morning...it seems to be fine.. ill update this thread if it happens again



its boosting about 13-14lbs now.. is that normal? and does boost hold strong up top or does it taper off a little?

 

I got a 15 % reduaction pulley installed a few months back on my 2002 MCS and I have also noticed a ticking or clicking sound coming from the pulley area in the engine. I can only hear it with windows down. Ticking goes away as soon as the engine is under load, even slight.

I used the old "scewdriver to my ear" technique to try to determine where the sound was coming from and found that it was loudest at the belt tensioner level. Thought it might a bad pulley on the tensioner.

I brought my car back to the local performance shop where I got the pulley installed and explained the noise to my tech. We looked it over and found that the ticking or clicking noise was being generated by the spring assembly on the belt tensioner. It looks like the spring or the thin metal plate that runs through it is vibrating slightly when engine is at idle. As soon as you put the spring under load, such as when you give the engine throttle, the ticking or clicking goes away.

My tech said it's nothing to worry about and I believe him.

I am far from being a mechanical expert, but I was wonderingif the slightly smaller diameter of the sc pulley (15 % reduction with OEM length belt)might just be causing enough slack to cause a bit of vibration in the belt tensioner which would create that light clicking or ticking sound?

I believe there are some threads on NAM dealing with clicking ot ticking noises coming from the belt tensioner, but I don't have time to look for them right now. If I remember correctly, some people had the belt tensioner replaced, but the noise remained.

Good luck.

 

Yea, the first thing im going to try is a smaller belt. I forgot to mention that the pulleys seemed okay to me (not dry or clicking at all)

 

Cool. Let me know if it corrects the issue

 

Just ordered a gates belt that's for the 15% pulley. Should have it by friday. So we'll see

 

You definitely need the smaller belt and I imagine this is the source of the noise. The tensioner isn't long enough to tighten the old belt so there is no tension to keep it quiet. The belt will be prone to slipping too, though the hot weather may make it sticky enough, but it often slips (Loss of power at high RPM/full throttle)

 

Hmm from what I read I thought id be okay as long as I bought a new belt. Wither way, new shorter bent on the way. Ill post back after the install

 

+1 on smaller belt I had the same issue

 

Everytime you install a new pulley you HAVE to replace the belt, start with that and see what happens.

 

T has a new belt on it right now. Its just oem sizeI

 

Smaller pulley = smaller belt

That's probably the source of all your problems...including low boost

 

that was it. thanks for the help guys. boosts just barely under 16psi at redline now.. seems a bit high, but i got my car from an old dude so maybe the supercharger is just good?

 

What belt did you install (part no.) with that 15 % that stopped that clicking-ticking noise?. I'd like to get my MCS to stop clicking-ticking too.

Thanks

 

i got a gates K060539. i have the top hole on the tensioner showing now. no noise at all and it pulls great now.

 

I just checked the belt that was installed with the 15 % sc pulley and it was a Gates K060539.

Funny that the belt tensioner is still clicking / ticking at idle. The shorter belt should have kept this from happening.

I wonder if I could go with a belt that's still a little shorter, like the Gates K060535? Would that be too tight? The K060539 is 1385 mm long and the K060535 is 6 mm shorter.

What do you guys think? Worth a try?

 

I double that idea