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Tue Sep 16, 2008 12:05 pm

I would like to adjust the timing on my '72 bus for the first time since the new rebuilt engine was put in. I believe that the engine in it now is from a '73. The problem is that both the '72 and '73 type 2 engine began with the engine code CB yet they have different timing adjustments according to the idiots book. My engine code is CB029520 can I tell which year it is from just that and if so does anyone know? Thanks.

Tue Sep 16, 2008 12:16 pm

This is about a close as you can get.

http://www.type2.com/bartnik/enginecodes.htm

EDIT: OK. I got lazy.....If you have the stock distributor from the 73 with a manual trans, this will help you identify it. Also, don't forget to check the arm of the vacuum can inside the distributor housing also. That will tell you about how to time it. By the way, this page is where you can get all the timing information when you DO have the actual distributor numbers.

http://www.oldvolkshome.com/ignition.htm#B1973M

Distributor: VW 021-905-205J, Bosch 0231 173 009 or 010 > 021-905-205N, 0231 181 005
Can Use: VW 021-905-205N, Bosch 0231 181 005
Points: 01 011
Condensor: 02 054
Rotor: 04 033
Note: Originally equipped with Speed Limiting Rotor 04 016 (5400rpm)
Dust Cover: 039-905-241, Bosch 1230 500 139 > 1230 500 147
Cap: 03 010
Distributor Cap Clip: 03-905-265, Bosch 1231 251 033
Parts Kit (Shims, Washers & Hardware): 059-998-211, Bosch 1237 010 007
Coil: 00 015 (Blue Coil: 00 012)
Vacuum Can: 07 113
Ignition Wires: 09 171
Spark Plug: W8CC
Timing Set At:: 10deg ATDC @ 800-950rpm w/strobe, vacuum hose(s) connected
Advance/Retard Range: Vacuum: 7-12deg Adv, 16-18deg Ret; Centrifugal: 9-14deg @ 2000rpm, 21-25deg @ 3400 rpm

Tue Sep 16, 2008 12:56 pm

Codes are merly a clue as to how that particular case was equipped when it left Hannover, you need to know your distributor number and exactly what model of carbs you have before performing any tune up. Internals can change too but don't effect settings as much. Also make sure you are reading the code on the case and not the fan shroud.

Tue Sep 16, 2008 12:58 pm

The correct timing depends on the distributor you are using, NOT the engine number. The engine number ONLY tells you what THAT case was when it left Germany.

Most 72-73 buses time at 5 or 10 AFTER with a dual vacuum unit dist WITH manifold vacuum connected and the retard side working.

If you have a later single vacuum unit that times at 7.5 before and you set it at 10 after, the bus would run gutless and very sluggish.

What is the distributor number that you have?

Tue Sep 16, 2008 1:58 pm

Ok so the numbers of the distributor are 0231 173 009, then 021 905 205 J. The number off the arm from the vacuum can on the distributor is 2605.

EDIT: Also the type of carbs i have are dual H-32/34 PDSI - 3 's. Not stock and if anyone knows of any guides for tuning these that would be great.

Tue Sep 16, 2008 2:26 pm

http://www.ratwell.com/technical/DualCarbs.html

Welcome to The Samba. learn to search. 8)

Tue Sep 16, 2008 2:39 pm

Vacuum can 07 113 means it should have 925 on the arm.

Your 2605 means it is a replacement vacuum unit. Part number 07 129.
It is NOT an air cooled VW vacuum unit. It goes on 1980 Audi 4000, 75-79 Audi Fox, 76-79 Dasher and a lot of other water cooler cars.

Your 021 J distributor specs WITH the 925 vacuum unit are supposed to be Timing Set At:: 10deg ATDC @ 800-950rpm w/strobe, vacuum hose(s) connected
Advance/Retard Range: Vacuum: 7-12deg Adv, 16-18deg Ret; Centrifugal: 9-14deg @ 2000rpm, 21-25deg @ 3400 rpm

The Audi Fox and VW Dasher times at 3 degrees after. I doubt very much that the 2605 unit has 16-18 degrees of retard in it. More than likely 8.

To check: set your timing at 7.5 before with NO vacuum connected. Now connect the hose that has vacuum at idle to the inner nipple on the vacuum unit. Read the timing now. The difference between 7.5 before and what ever it is after now will be the amount of retard degrees in the vacuum unit.

You can also check the advance side this way.

But you really should get the correct 925 vacuum unit.

Tue Sep 16, 2008 5:42 pm

Thanks for the info, any suggestion though for at least how to find out the static timing mark? At the moment I don't have the strobe timing light, just the static one. All I need is to get it statically timed at least close and then I will get the strobe when I get paid. Should I just trial and error with the static timing since my parts are not all stock?