LPMM

Getting ready to do some last minute stuff before taking the car out of winter storage and upon doing an engine visual check, I discovered that the fan is delaminating and starting to score the housing.

Upon looking up the part number and prices, it appears that the Turbo one (964.106.015.21) is much cheaper than the C2/C4 one (964.106.015.31). Any difference between the two?

Time to call Sunset back and add that to the list. Anything else to order and replace at the same time as a precaution? Special tools needed?

RW964

Whilst you are in there change the fan bearing as well you are going to have to get the bearing off any how .. All of the forces are on the bearing makes sense to replace that at this time .. So search I changed mine out about a 8 months ago and found on links it showed the distance from where the pulley mounted to the fan and the body of the fan to be a different measurement.
This would make the fan pulley closer to the fan throwing off the pulleys
so the belts will not be straight. I am not sure just what I have put a eye on .

Rocket Rob

I would replace the fan bearing and belts while you are in there. Also, how old or new is your alternator? It might be a good time to replace it or have it rebuilt.

LPMM

And the slippery slope begins Is the bearing #28 on the diagram below?
Roger on the belts, not sure about the alternator and how old it is but holy crap on the price of a new one. Part # 964.603.156.01 lists for about $1,500

Rocket Rob

Yes, the bearing is #28.

As for the alternator, I have replace a few over the years. The prices are much better if you look for a non-Porsche branded one. They are made by Bosch. EBS Racing has both rebuilt and new ones for $177 & $225 respectively.

http://www.ebsracing.com/ShopByVehic...rnator&mode=PA

Andy Roe

I think the Turbo fan has a different housing and you'd have to change that too (and from what I understand, this is very expensive). I've seen a thread about this before - I'll try to find it.

LPMM

Thanks for the link for the alternator and I'll order the rest of the parts from Sunset.
As for tools, I take it I would need a 12-pt (or "3-square") 10mm bit to hold the shaft in place (not sure I have the special tool) and a 5mm hex drive for the cap screws.
My biggest dilemma will be to pick a color for the fan. Then, I'll cross my fingers that I don't goof up when I do it, this will be my first project but I guess one has to start somewhere.

Silly question: is there a belt tensioner to release the tension or does it happen when removing the pulleys?

Rocket Rob

For tools, you will need the 10mm triple square, a 10mm socket to remove the nuts holding the belt pulleys and a 5mm hex key to loosen the bolts holding the alternator strap.

No belt tensioner. The belt tension comes from the pulleys themselves.

If you are buying a new fan, double check if the bearing is included. I've bought two fans, one came with the bearing, one didn't.

TYPE911

Had the same issue on my Targa last fall. Ordered new Fan from Sunset, yes it includes the bearing. Based on the many posts I have seen here & on The Biird it's common.

jimq

Mine did the same. I got it from Sunset in Oregon and it came with the bearing already in the new fan. They were the cheapest I found at the time. Dont waste your money on used as it would probably be as old as the one you are pulling off.

gristle101

Andy Roe said it. The Turbo fan is different, and it requires a different housing, which likely costs in the neighborhood of $900-1000. Word on the street is, however, that the turbo fans have a lower failure rate. They also move more air into the engine, cooling things off more efficiently.

This subject is discussed extensively here in this very recent 993 thread:
https://rennlist.com/forums/993-foru...calgary-3.html

LPMM

Thanks all, I think I'll stick with the C2 fan. I had talked to Luke @ Sunset about getting the rear blower bypass and I sent him an email to get pricing on the additional parts I need.

LouZ

Some may recall that my fan and alternator blew apart 2 weeks ago. I have a reman Bosch alt from Advance Auto online and it was direct shipped from Bosch in Georgia.

The fan, along with all new pulleys and shims are on order from Sunset, all of the extras are needed because I had the early version of the fan.

Should be back on the road by the weekend (if parts arrive soon!).

g60pops

What is the difference between the earlier and later fans?

Navaros911

My fan and housing looked exactly like that and I drove her for another 6 months. Not that i'm advising this type of solution.

I ended up going with a used fan from my mech's parts car. That was much faster than the 6 weeks shipping. It was at the tail end my engine rebuild... so got too impatient to wait for a new fan. the used one was cheap so if it fails in two years i'll deal with the problem then.

Now, since these fans are prone to wearing out around the 20yr mark on most 964s it seems, there must be a better solution.

The question here is very valid: what is the difference?
Alternative fans? Perhaps carbon fibre or polyester?

And how come I didn't have this issue on the 5 bladed fan from my Carrera 3? That car was older than my 964 and there was no sign of scoring. On top of that, plenty of used fans around for cheap.