Q8drill

I just replaced my fan hub to RS hub with a single belt, the problem is the battery and ABS light illuminate, do I have to replace the fan too?

Vandit

Let's see what others say, but i'm guessing the RS pulley will spin the alternator slower, causing lower charge. Maybe your alternator was going out already, so spinning it less only exaggerated its failing ability to charge. Is this problem at idle only or throughout the rev range? Take a measurement at the battery at idle to see if it's charging.

Vandit

Instructions on how to do this.
http://tech.rennlist.com/911/pdf/add...rainadrian.PDF

Goughary

FWIW - I just did this with mine during my recent top end rebuild - and have zero issues with charging the battery. So far...

fuch

Great post,thanks.....

Pesty

Great write up. Looks easy enough assuming it will all come appart.

Silly question time. my mechanic today said my bearing was noisy. does the RS version reuse that bearing or come with its own?

thanks

Goughary

Fwiw back in 2012 (see above) I had said I had no issues with battery charging, which is still true. However I am switching back to dual pulley because I have found that our cars don't create enough amperage out of the alternator with the single pulley to run well under 3k rpm. So basically kills low rpm throttle response and spark in general is weak down there.

As to the bearing. The conversion takes away the fan bearing and leaves you with only the alternator bearing. If he said your alternator bearing is going have that done before doing the single pulley...

Pesty

He said fan bearing IIRC

don't want to mess with electrics if its going to give low volts. Ill get a new fan one and leave the twin belts

cheers

Goughary

Yeah. It works fine, just not ideal for normal street driving. Sluggish at low rpm. And I assume lots of potential carbon buildup since very weak spark down there. Once you are over 3k, it's full amperage from the alternator and nothing to worry about. So until I switch, I am 3k+ all the time.

Gus

Charging is not an issue. I did the conversion and the first big test came driving back from Road Atlanta after a DE. Accident in down town ATL blocked all 4 lanes. Traffic was stop and go at 2 - 3 MPH for 2 plus hours. No charging issues. I run an electrical power steering unit so there is a significant drain at low speeds. But all worked well and no issues. So think that the charging issue can be forgotten.

backitoff

Great write up!!! Makes me want to do this!
Can someone say what is the part number and cost of the RS hub? Also, I'm guessing the belt would be the RS belt?
Thanks

Gus

The belt should be a standard belt - just a smaller diameter, believe it is a 770mm length, width remains same.

Gus

Correction - belt used is standard belt 776mm. I also installed the smaller crankshaft pulley which reduces belt size to 750mm.

Pesty

Thanks for the write up. I stuck with the dual set up but used your pics t do it.

Very easy. My bearing came out with the fan. Only problem I had was getting the alternator housing back in place. Couldn't get it back far enough to clear the bottom pulley. But got there in the end.

Michael D'Silva

Interesting...
My bearing came out with my fan also...

So to now remove it from the fan, is it a matter of using the 3 prong puller again, but pushing on the bearing instead to push the whole assembly out?