Hi guys, Last weekend I went supercharged, installed by myself which took hours & hours & hours - anyway its all been smooth except for a noise i'm hearing when accelerating from 1000-2000 rpm its a low pitch rumbling noise, above approx 2000rpm i dont hear it anymore maybe because of the rest of the engine noise, i started diagnosis by removing the SC belt and going for a short run, the noise dissapeared isolating the noise to the supercharger - is this noise normal? I tried taking a video on my mobile but its rubbish quality sound. SC although second hand has only covered 10,000 miles.


Steve D

could be the bearing in the pulley.... or if the noise is present at idle but goes away as soon as the revs increase its the straight cut gears on the nose drive and nothing to worry about.

if its still there after a slight rise in rpm then i would have a look at the oil quantity to be on the safe side, but a rumble norm indicates a bearing

Think I know what you mean.

Check if all the bolts of the TTE bracket are torqued properly, the cooler isn't rubbing anything and all the hoses are running free.
with 10.000 the charger won't be under suspicion but do check the aluminium screws on the nose of the SC. These are weak (read the Sc refurbishing project by Rob) and tend to loosen. Furtermore the pullybearing on the nose (Warner Electric product) has some play and wil make a vibrating noise when it it is too loose (Loctite will solve this).

Thanks for the reply Rob, there's no noise at idle & the noise dissapears at 2000RPM, I checked there was oil in it last night & there seemed to be plenty although i didnt check the exact quantity.

Only thing thats concerned me right from the start was the fact that when it arrived in a box on the door step there was no covers fitted to the SC so it was wide open to rubbish, infact at first there was a piece of cardboard jamming it from moving! , I went in with an inspection mirror & torch removed the offending piece & gave it a good blow out with 120psi compressed air, it was operating smoothly afterwards.

When the belt was off this morning i moved the pulley a few revolutions & i could hear gears working inside like you'd expect but it was nice & smooth.

with the belt off wiggle the pulley a bit up down left righ - dont rotate it. if there play? also u can remove the 3 chocolate strength screws and then just turn the bearing - this should sound smooth. you may have to align the cover again but thats easy easy

Reporting back - removed the belt - no play at all in the pulley, removed the 3x T20 torx screws, which were barely tight - certainly not loctited, spun the coupling which was smooth, refitted the 3x torx screws using a dab of loctite 270 threadlocker, refitted the belt.

Quick roadtest resulted in no odd noises at all!!

Like you said before (Rob) this could be a common issue, anyone with this SC should really check it, one word of warning when the 3x screws are removed and you spin the black cover/pulley the screw holes dissapear or appear to turn into half holes!, it was a bit tricky with a screw driver & turning the pulley to line up the proper holes again, its best if you only want to loctite the screws to do them one at a time so you dont loose alignment of the holes!.

Steve.

if the screws were loose then the old clutch plate thats used for the magnetic clutch would have been a bit loose and prob making the funny noise - ther eis no reason for it to be in there when used in our setup to i binned mine.

Extending this topic a little, the nearside piping is soooooo close to the air con pulley & its rubbing some little black box on the chassis marked with LH (left hand), anyone know what this box is, can it be re-located?, if not i might heat up this pipe & compress it a little in a vice to stop it hitting anything.

it does run close to the air con pully but the pipe is compressed from what i remember. cant picture the box as dont have the car here. 1 thing to look for is that the pipe doesnt rub against the air con pipe in the area of the ECU box.

Little black box looks a lot like a tilt sensor for the alarm system, is that possible?

no tilt sensor on the IS but clearance shouldnt really an issue except in the area of the pulley.

Any chance of a picture Steve ? I know some need a cut in the Fan assembly nr the pulley, but nothing else.

Tried to get a good photo of the black box but its near unphotographable!!, its just below the AC pipe crossing the chassis & right behind the SC pipe, it's held by a metal frame & 2x bolts.

Like Woz said, did you cut the little bits off the Fan cover?

Stav

yeh i did, still that little black box is making it really very tight beside the a/c pully

I missed this tread somehow.

But the original post of a rubmling noise, sounds like what mine was doing. I have not noticed it recently, but i think its just been drowned out by induction!

I will check the screws you mentitoned. Also, my bracket/cradle is snapped, in the usual place, i suspect. Could it be that?

the sensor is 1 of the frontal collision sensors for the airbag system

Thanks Mat - never considered that one, Fortunately I never re-mounted it, instead I removed the offending intercooler pipe - bashed it a bit with a plastic hammer to reshape it as it should have been