The next time that anybody takes apart a 993 dual-distributor with an original belt could you please take a photo of the id markings on the belt? I know Porsche spec'ed a different belt (possibly 100% synthetic(?) to get around the original ozone problem) to the one used in the 964 dual-distributor. And I've always been curious to know which version is being sold in the aftermarket by Gates.

 

I could take a photo if absolutely necessary.

I keep a log of technical info and these are the markings that I noted on the belt that I just took off the other week

Markings on the original distributor drive belt:
5104 NICHT KNICKEN CT 1234736002

Information found on the internet:
ContiTech CT1032 Toothed Belt
Number of teeth: 57
Width of belt: 8 mm
OE-Nummer: Bosch 1234736002 (Bosch number grouping: 1 234 736 002)

Strange that the belt would have a CT on it which I assume stands for ContiTech, yet the number is a Bosch number.

 

GATES 114XL031HT SPCL 0270SS

Counted 57 teeth and measured 8 mm wide.
This Gates belt is available from Pelican Parts for $6.50

 

Is this the same belt, the listing claims it is for (89-94)

http://www.pelicanparts.com/cgi-bin/...01%20per%20car

 

Which has the same dual distributor.

I bought my belt at Pelican Parts. It is dimensionally equal to the original one in my car.

Remember to take note of the rotor positions with respect to each other before you remove the old belt, provided it was still intact.

 

Looks like its about a 7% chance to break over the lifetime of the car. I wish all the parts on the 993 had the same reliability!

 

NICHT KNICKEN just means: Don't bend sharply.

I have a new Gates' belt still packaged and it has a Porsche number on the pouch: 930-602-134-00

8 mm wide and it has 57 teeth on second count.

 

Besides shocks, & a couple of other things, we are not to far off that.

 

Replacement end cap for the secondary distributor.

As recommended by various do-it-yourself web sites to use the following method, I chose not to use a small screwdriver to remove the end cap by prying at the edges of the distributor body. I didn't want to mark/gouge the distributor body. BTW, the cap is not available separately.

Instead, the original end cap was removed by drilling a small hole through it and then using a hooked pick to then pry it out. The metal of the original end cap is quite soft and thin.

As a replacement for the original end cap, a 1 1/4" frost plug was used. One with a 1/4" wall height fit perfectly. Not bad for under $2.

The inside edges of the distributor body where the stake marks are located were filed down smooth using a small jeweler's file. This made tapping in of the frost plug possible.

Also, so that the edge of the frost plug does not scrape the distributor body thereby possibly introducing aluminum shavings in the bearing area, the edge was filed at a shallow angle with a fine flat file.

The end result...

 

Dual-distributor Bosch 0 237 503 004 bearing issues

This time I took a closer look and here are some measurements:
Primary shaft is 12.44 mm on top and 11.99 on the bottom.
Secondary shaft is also 12.44 mm both ends.
Three bearings (1 on top of primary and 2 on secondary top & bottom) are the same: 32 mm OD, 12.45 mm ID, about 10 mm wide are a special order NLA.
The bottom bearing on the primary shaft is a dual set-up with a needle bearing for radial and a ball bearing for axial loads 22 mm OD & 12 mm ID about 25 mm wide total.
Both bottom bearings on the primary are open once the shaft is removed and can be checked and lubed.
The other 3 bearings are sealed and almost impossible to clean and lube. Someone posted that a 6201 bearing can replace these 3 but I don’t see how since the ID of 12 mm cannot fit over the shaft being 12.44 mm.
One would have to find bearings with ID 13 mm, OD 32 mm, about 10 mm wide and use shim stock to make up the difference of 0.5 mm on the ID.
And the combination bottom-bearing on the primary shaft is impossible to find. If those bearings are worn out, one has to have the distributor professionally rebuild i.e. Steve Weiner or Bosch or?

 

I had the following symptoms:
About 200 miles ago noted hesitant power; subtle miss-fire and CEl with "random miss-fire: error code.
Changed all 12 plugs and noticed upon re-inspection that the exhaust plugs were firing. So I assumed the wiper distributor was good. However, the hesitant power feeling remained; but not as obvious. And still CEL code of "random miss-fire". So just today got new cars+rotors and see that the exhaust wiper distributor just spins around with no apparent tension. Also, twitching the intake distributor rotor has no effect on the wiper rotor. I see the belt, it looks intact, but when spinning the wiper rotor around the belt does not move. QUESTION: If I need to move the car (I am using a friends garage) can I back it out at least using just the intake distributor ?

Also, who can I send this dist to for new bearings and belt ?

Thanks,
Patrick
1996 C4S 172k miles (daily runner)
2007 GT3

 

Well, it sounds like you have already driven the car 200 miles on one distributor... just pull the coil feed to the distributor cap that is not working, and you can drive it. The car will run on 6 plugs, its a misfiring plug (i.e. at the wrong time) that is the issue if the belt breaks. If you disable the broken side of the distributor, then its not an issue.

Cheers,

Mike

 

Check eBay; you might get lucky. For a spare, I bought a new Porsche distributor for less than the cost of a rebuild.

As for the rebuild of my original unit, I did that simple DIY myself. Its under $15 in parts.

 

here is one!

 

that picture came from this thread: https://rennlist.com/forums/993-foru...mp-sensor.html

I had my distributor rebuild not too long ago with a new belt, bearing and pin.
The belt that came out looked in very good shape. And that is after more then 200,000 km's