At idle I get a rattling noise out of the front of snout or drive where the pulley is , is that normal or is the brg gone ??? Thanks in advance...:teeth:
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At idle I get a rattling noise out of the front of snout or drive where the pulley is , is that normal or is the brg gone ??? Thanks in advance...:teeth:
hey, Im new to this website, but I registered because of the same problem...I have a B&M 144 Supercharger that was making insifnificant pressure on a small block chevy. So, I recently had it rebuilt (I would like to keep the company that did it anonymous because as of this point I cannot say they did anything wrong) with all new bearings/seals/the housing was milled/and new teflon strips were added...so far as I was told the snout was untouched and the gears, being in good shape were reused. Once I received it back, I checked out the handiwork, spun it by hand (obviously, it was not as free spinning as before) and it was smooth. I filled up the gearcase with 90 weight to the fill hole on the front side of the front cover (not the top obviously) and spun it again...still felt smooth. From there, I installed it back on the engine, and hooked everything back up. Upon start up I heard a squeal and immediately shut it off (i cannot recall any "knocking" or "rattling", but this could potentially be due to the fact that I wasn't listening for it). After tightening the belt a tad further (I have a manual tensioner with the one bolt and such, and from my experience with belts it is nowhere near being too tight) I proceeded to start the engine again. This is where I heard what I assume you are refering to as a "rattle". I would describe it as a light "knock" i suppose, so I hope we are on the same page. Anyway, I did not run it long again, however, I did hit the throttle once and it did increase in rythm with the engine. I called the company that rebuilt the unit, and the following is what I was told: (I am currently learning as much as I can about roots style superchargers and what follows might sound stupid to you, but I am at a loss, so...) I was told, "pull the belt back off and turn the pulley by hand again to feel for backlash in the gears"...although, obviously, just being rebuilt by the company, he assured me that it should be fine. He then proceeded to say, and I quote, "It may make that noise until it has warmed up and worn itself in". Now im not one to usually question someone with more experience than me, but im not 100% on this one...I really dont want damage what should be a "new" unit. I realize that this "novel" isn't really going to help you in particular, its just that I was looking for the same answer I believe, and I thought i'd tell my tale and give as much details to whomever else might stumble this way.
Any update?
I have a B&M 144 blower on my SB Chevy. I bought it new and it has about 35,000 miles on I. My blower would rattle some at idle. As an experiment I set the idle up a bit and the rattle stopped. I believe the noise comes from the gears in the snout, caused by the blower speeding up just a bit then slowing down. There is no load on the blower at that RPM so it is possible for it to do that. Anyway, with the idle set up, I no longer have the noise. One additional factor, I added a Holley HP Throttle bode EFI to the car and with the computer control the engine runs much smoother than it did before. JMHO.