jeff522

I'm fixin' to replace the alternator belt on my 993. Any tips on on it and how to deal with the AC belt. Also would it be a good idea to replace all 3 belts. I have them. I all looks pretty strait forward, but on a 911 looks can be deceiving. Thanks in advance. My garage is a mess right now. I'm almost done with my 97 E420 engine rebuild.

BobbyT

I like to replace all three belts at once, then you know they are all good.

Full details here: http://pcarworkshop.com/index.php/993_-_Belts

1. Use ONLY genuine Porsche belts, the ones that say "Porsche" on them.
2. Get the Krikit belt tension gauge, go here to learn how to use it:

kjr914

Belts are not difficult. do it step by step the first time and layout the parts in the order you remove them. I find the magnetic parts trays are great for helping with this. Most impt is getting the shims back in the right quantity and order.

Pcarworkshop has the details as stated above and +993 on the use of Porsche belts.

Other hints:
Get a proper 12pt tool to hold the alt shaft. Here's a couple of ideas, but I really like using the 12pt I got from snapon via mail order...see last post in this thread:
https://rennlist.com/forums/993-foru...ator-tool.html

Patience with getting the belts down under the crank pulley....damn Porsche engineers saw fit to put 2 welded-on mounting nuts in the way and it is frustrating. I have a super long 18"+ flat bladed screwdriver that helps with the process. As well, I've had good luck pinching the belt into a tight bend and inserting it starting from the center of the crank pulley, rather than trying to "hook" the pulley from the outside. (this may make more sense when you are in there, hard to describe).

Use some tape to hold the fan belt sensor out of the way while you putting the belts back on. Just makes things a little easier. tape around the wheel and onto/around the body of the sensor.

Enjoy tinkering with her!

Quadcammer

piece of cake on the NA cars, but the a/c compressor is a pain.

EMBPilot

some stuff that popped up on me that i needed...
- 24mm wrench
- yes you need the 10mm triple square, but a stubby socket version for a 3/8th wrench is ideal...
- get a 24mm crowsfoot so you can properly torque the shaft nut to 50nm +-5nm
- 5mm allen sockets are helpful for the pulley bolts, also order new ones (bolts).
- good idea to replace the belt sensor
- AC compressor placement is a pain in the ***. you can order a belt thats slightly longer by a few mm's and it will make the re-install easier and the compressor wont sit up against the adjustment stop.

my recent adventure...
https://rennlist.com/forums/993-foru...tions-ect.html

IXLR8

It sure is, for two reasons.

1) the OEM 13 x 1085 belt is too short and cannot be removed off the pulley without unbolting the A/C compressor and tilting it in towards the engine. Other owners I have spoken to noticed the same issue. Conti make the AVX 13 (La) series of belt in 1100, 1118, 1125 lengths. I'm going to try one that just slips over the pulley when the A/C compressor is right up against its stop on the mount.

2) its impossible to get to the A/C compressor adjuster locknut without an ultra-offset 13 mm wrench. I never found a wrench with that much offset, so I made this mod to fix that issue.

Quadcammer

you said it. the oem belt is definitely short. Might make sense to use the longer belt.

I haven't even messed with the adjuster since the compressor is pretty much against the stops anyway.

jeff522

I finally got around to replacing the alternator belt. I was surprised how easy it really is to do. I'm glad I had all my tools that came with both of my 911s. I used the Porsche crowfoot and wench designed to do the job. I did use a torque wench for the finial setting. The whole job took maybe 20 min. The hardest part was getting the nut off the alternator shaft. Some WD-40 and a few min took care of that. I am going to get a longer belt for the A/C. I just cut the old one off. By the way, who puts two overly long bolts down by the crank pulley? If they were a 1 mm shorter they would not be in the way when passing the belt at all.

IXLR8

Jeff, if you hang on a couple of days, I'll let you know if the 13 x 1125 that I just ordered fits. The belt will be in tomorrow.

Its 40 mm longer over the stock belt or 20 mm longer per side, which should slide the A/C compressor about 14 mm horizontally in its mount (20 cos 46°).

CarreraX

Also Patiently waiting for the results

got*ki

I still can't figure out why Porsche made those three pulley bolts wiith such soft metal. Darn things are almost sure to strip. Aside from removing a stripped bolt, everything else is relatively easy...

IXLR8

The Contitech AVX 13 x 1125 La that I picked up today is too long. The AC compressor was all the way against its furthest stop and the belt was a bit slack.

From that same manufacturer and series, I think the 13 x 1118 would still be too long and the 13 x 1100 too short to slip over the AC compressor pulley.

I'm going to hunt down something around 13 x 1110 and give it a try.

Well at least I got good at holding those square nuts in position; didn't drop one.

CarreraX

Thanks for the update! Really appreciate it!!

Luftd993

I tried a 13 x 1120 for the A/C and it was far too long.
I have a 13 x 1100 on the way and will report back.
I don’t mind removing 3 bolts to remove/fit but it would be good to have a bit of +/- adjustment.

IXLR8

I'm also looking at offerings from Gates. BTW, I just checked on-line and the Porsche belt is still listed as 12.5 x 1085, yet they supply a 13 x 1085 which rides higher in the pulleys making it effectively shorter.

Not a big deal while working in the garage at home, but roadside I'd prefer a quicker fan or alternator belt change.

Porsche should have made the mount a bit longer and extended the adjustment slots by another 25 mm. As it stands now, the AC belt is as tight as I'd want it and it is at the most forward stop on its mount.