hi guys ,,,

My friend has 2005 manual 5speed 4.8L gmc Z-71 truck, he installed a magnacharger with 3.70 pulley 3 months ago and ran on it around 3000-3500miles ,, two days ago he was racing a guy with bmw 645 ,, they started from second gear when he pushed his truck to the third gear the magnacharger shutdown!! the roots's sound disappeared, the power went down, and the truck ran as the stock truck even worse. The supercharger's pulley works its turn around but we can't hear any sound from the supercharger even at high RPM!!


Is this happened before?

 

Have you checked the blower or intake manifold for damage? Possibly the diverter valve stuck open? Hopefully BlownChevy will chime in.

 

Blown02Sierra ,, nothing looks bad from outside, no leaks engine's sounds normal like
a stock engine!!, even at high rpm the supercharger has no sound at all


anyway thank you very much for your support

 

If you take the belt off you should be able to rotate it by hand back and forth. You should feel the resistance from the rotors and they may make a slight clunk if turned. The bypass valve does sound like a possibility though.

Dave

 

Sounds like a broken input shaft on the supercharger. Even if the bypass was open you'd still hear the whine.

 

sounds like the blower drive shaft might have taken a **** on ya. Give Magnuson a call 805-642-8833, ask for David.

 

Bowtie70SS,, i'll do it ,,, thank you very much



James B. ,,,, yea i thought that too, because the pulley turn around but nothing else. Thank you very much



BlownChevy ,, Thank you very much for your support ,, i will call him as soon as possible.