Back in May just before my outing at Motorsport Ranch road course I had started hearing a very loud whining sound that to me sounded like a bearing.

I put a stethoscope on the 3 pulleys that sit on the Vortech mounting plate and I thought I had identified one of them as being the culprit. I found out through Vortech Engineering that the pulleys could be found at Napa Auto Parts stores so I replace all 3 of them just to be sure. Unfortunately the noise was still there.

Next I removed the cog belt which would single out the blower itself. You will see this in the first video that the cog belt is off but there is still a great deal of bearing noise so luckily the blower was ok.

This only left the bearings in the jackshaft housing. These bearings could only be purchased through Vortech directly and were $15 each (2 bearings in the jackshaft housing).

I will attach some pics I took along the way through my journey of replacing these bearings...

 

First is the picture of the belt routing from the Vortech installation manual. You can see the 3 supplied pulleys (2 grooved idlers, 1 smooth idler). These are the 3 pulleys I replaced first.

 

Now came the fun part ... trying to get the jackshaft assembly apart. I ended up picking up one of those strap wrenches from Sears. It was the only thing I could think of to secure the cog pulley from spinning while I tried to break the shaft bolt loose. It was also what another forum member (booger) used when disassembling his jackshaft to replace the pulley. All the bolts in the jackshaft are secured by loctite so they were a b!tch to break loose.

After repeated attempts with a ratchet and the strap wrench it was obvious I was getting nowhere. This is where I turned to the electric impact wrench which finally did the trick...

 

Once the main bolt was broken loose, it was necessary to hammer the outer pulley off by using a socket to push the jackshaft through the mounting plate. Then there are 4 allen bolts holding the jackshaft assembly to the mounting plate.

Once the jackshaft assembly is removed from the mounting plate, the shaft itself will be held in the outer bearing. After removing the cog pulley you can tap the shaft through the housing which will push the outer bearing out. This will allow the shaft to come out of the housing.

The inner bearing (cog side) will need to be tapped all the way through the housing. Both bearings are pressed in.

The only picture I took here are of the bearings after I had them out. I took off the side plate of the bearing where you can see in the outer bearing, the grease just turned into gel!!!

 

The only other pics I took are of the Vortech bypass valve while I was under there. Although you can't really notice it all that much you can see quite a bit of oil blow-by. It seems that this is an issue that goes back and forth on the forums, especially in the forced induction forum.

Many have questioned the validity of an oil catch can for the VQ35. On a VQ35 motor with FI, you are increasing the chances tremendously that oil is going to pass from the crankcase back through the intake where it will either sit in the intake manifold plenum or be ingested back into the cylinders. This is where sludge build up comes from. Anyone that has pulled the upper plenum off their own cars to install a plenum spacer or iso-thermal gasket has probably noticed small pools of oil that have collected.

With a Vortech setup, the crankcase vent is redirected back into the air filter where a tremendous amount of intake air pressure is created forcing any crankcase oil back into the intake. The difference with a Vortech setup is that the bypass valve "BOV" sits right before the FMIC and bleeds off pressure when not at full throttle. The way I'm seeing it is that a lot of this blow-by oil is actually shooting right out of the bypass valve instead of going all the way through to the intercooler then intake. I'm not saying that 100% is going out the bypass valve but a good percentage.

Once oil enters the intercooler, it will coat the walls and reduce the efficiency of the intercoolers ability to cool the charge air. I have been looking into various different oil catch can setups although many are not capable of supporting the increased air pressure created by the turbine (SC or ST or TT).

 

Replacing the bearings in the jackshaft housing was not all that simple. As I mentioned the bearings are pressed in and these bearings are pretty large. When you are pressing bearings, you should only be pushing down on the outer race of the bearing as to prevent damage to the bearing. Typically to do this you would use a socket that's about the same size as the outer race of the bearing. The bad part here is that this would require a ~1 3/8" socket which don't come around that often . We ended up using 2 of the same size sockets side by side so that the inner and outer race were being pressed with the same pressure.

Last but not least, the video's I took with my camera ...

The first one I took after replacing the 3 idler pulley's and with the cog belt removed (supercharger is not spinning):
http://videos.streetfire.net/video/d09c14a3-da0f-4e12-9f53-2cbcfd728006.htm
The second is after I replaced both jackshaft bearings
http://videos.streetfire.net/video/79fe83ce-5a1e-498f-8605-313802d56bdc.htm

 

Glad to see you got the SC fixed . One thing you might want to try to assure the oil in the IC pipe is from the Crank case breather hose . Ive always just let mine dangle out towards the bottom of the motor . Ive never gotten any blow by from it . But did end up with oil in my IC pipe . It was from the SC it self . The seals in the SC went bad and was leaking into the system . The blow by oil always seems to be dirty thick oil . And the engine oil that I got into my IC pipe was pretty clean compared to what Ive seen .

 

Mr. Handyman. I would say *** it and send it to someone to fix.

 

Well ok ... just make sure you can fit me in the next time my car breaks!

 

BeerViper, you just saved the day for me. I had the exact same noise you had.

Btw, this should be posted in the FI forum for everyone.

 

Hey Dan, glad my post could help ... it is in the FI forum but I think I just posted the link for this thread.

 

Just to make sure, this is the noise you had, correct?

http://s114.photobucket.com/albums/n...t=MOV03078.flv

 

+1^^

 

Yeah Dan, that sounds just like mine did. However I started by changing out the 3 idler pulleys first which had no effect. That's when I decided to order the bearings for the jackshaft directly from Vortech. Once I got the inner bearing out of the jackshaft, there was no doubt that it was the culprit.

You mentioned in the post over on my350z that you took the cog apart but I'm assuming that just means you removed the cog pulley? Did you take the actual jackshaft apart and replace the bearings? I can almost guarantee that is what your problem is based on the video you posted.

 

Ya, based on your threads, I immediately ordered the bearings. I tried diagnosing the sound with my ear and I was almost sure it was the top idler pulley, because that's where the sound was the strongest. You came to the same conclusion, but found out this wasn't it. Bearings should be here by tomorrow and then I will replace them via your instructions. I just took the cog belt off to see if the sound was caused by the blower. Thanks again.

Btw, do you remember the part #'s for the idler pulleys? I know you posted the part # for the grooved pulley at Napa, but can you also get the smooth pulley at Napa as well? I am thinking of replacing those as well, since they look a little worn. I am getting a slight squeal as I take off from a stop or engaging 2nd gear in a slow roll. I know its not the belt, because it is on very very tight. No squeal on startup at all. The squeal only last a second and comes during the time the clutch is engaging to when it is completely depressed. I'm hoping replacing the idler pulley's will solve this.