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Fri Jan 28, 2011 8:00 am

Glenn wrote: babarogue wrote: I disassembled a "small" vac can, and a "big" one, so here are some pictures (I didn't want to overload this thread):
http://www.thesamba.com/vw/forum/viewtopic.php?p=5097445#5097445

I hope it could be of some use :D
Please repost them in this topic so everything is in one place.

Sorry, I guess I did something wrong there, so the whole topic under the link does not exists :( . I'll try once again here.

First, the way I use to open the canister. It may not be the best way, but it's not too difficult to do it this way.

Next, the big canister. It has the number 095 stamped on it, it was taken from 111 905 205AA distributor.

The last picture shows the reason why it was not working properly. Actually it was capable to hold the vacuum for some 5 to 6 seconds.

Now the small one. It is taken from 113 905 209AL distributor. The nuber on the rod is 461.

It has a spring inside, lenght=25mm, thickness=1.5mm

Please notice the size of the hole in the canister tube.

For comparison:

The thickness of both diaphragms is 0.2 mm (as I was able to measur), The diameter of "095" diaphragm is 82mm and its cover diameter is 80.5mm. The "461" diaphragm has a diameter of 64mm and its cover has diameter 62.5mm.

Fri Jan 28, 2011 8:06 am

On the diaphragm material, they are both same, similar to those in fuel pumps, only thinner.

Fri Feb 04, 2011 5:21 am

A small update: the dimensions of the pull rods. First the big one.

It si interesting that the coutout near the diaphragm is 7 mm in size. This defines the total amount of movement of the rod. Converted to angular movement this turns out to be 20 degrees, which confuses me a bid, because the total amont of advance for 111 905 205AA should be 32 to 35 degrees.

Now the small pullrod, 461 dimensions.

Here the size of the gap is about 2.5mm.

The "t=2mm" is the thickness of the rods. t=1.2mm in the upper picture is the thickness of the disk for the bigger one. The thickness of the disk of the smaller one is 0.8mm

Mon Feb 07, 2011 9:12 am

Quote: Now the small one. It is taken from 113 905 209AL distributor. The nuber on the rod is 461.

A little correction, the distributor is not with 209AL in the end, here are the data:
JFU 4 <--
Bosch nr 0 231 146 101
VW nr 113 905 205AL

The number on the rod is 461.

Please apologise.

Sat Feb 12, 2011 10:44 am

Excellent contribution to this thread Babarogue.

Thanks for moving it here Glenn.

you can certainly see why the steel line is so important and why the fumes from petrol will ruin the diaphrgam given time.

What does the canister look like when you are done?

Sat Feb 12, 2011 8:46 pm

With all the different distributors that Vw had, are the main differences with advance/retard in the vacuum cans? Or are there a lot of differences with the distributor bodies and the centrifugal weights themselves?
If its mainly with the vacuum cans, I'm surprised nobody makes a adjustable can that you can dial in your advance or retard. Or is this already available?

Dan

Sat Feb 12, 2011 8:49 pm

If you look at the charts in the various Bentley manuals you'll see there were differences in the centrifugal advances as well. Not huge differences but they were there. Some vacuum units were quite similar in characteristics as well.

There are no "dialable" units for stock distributors. Now, the distributors used from 1965-1970 DID have adjustable return springs for the vacuum advance - but the overall amount of advance for these was always a function of the canister, not the spring.

-Andy

Sat Feb 12, 2011 9:16 pm

Are the weights and springs on the centrifugal advance similar to a small block chevy?
With a sbc, you can change springs to change rpm when the advance "hits" or modify the weights for more or less advance.

Sat Feb 12, 2011 9:20 pm

I've never seen the inside of anything except VW distributors so am not able to answer that question. Sorry!

Sat Feb 12, 2011 9:24 pm

Danpa wrote: Are the weights and springs on the centrifugal advance similar to a small block chevy?
With a sbc, you can change springs to change rpm when the advance "hits" or modify the weights for more or less advance.
They are totally different.

Changing the curve requires a lot of experience since there are no "kits" out there that will give you predictable results.

I restore the old cast iron models and have a bunch of hacked up parts I've removed from cores and had to replace with good used parts. I've tested a few as they came in and the modified curves make no sense to me.

It also helps to have one of these to see what your modification actually changed.

Tue Feb 15, 2011 5:03 pm

Quote: Excellent contribution to this thread Babarogue.

Thanks for moving it here Glenn.

you can certainly see why the steel line is so important and why the fumes from petrol will ruin the diaphrgam given time.

What does the canister look like when you are done?

Thank you tasb, I hope someone can find this useful. As for the looks, I have to admit they don't look as good as new, but they are ok, no leaks at all. The big one I tested in the car, and it worked fine: 1200 ccm engine, 30pict3 carb, 111 905 205AA distributor, 7.5 deg ignition advance static. The small one I'll test sometimes later, with 113 905 205 AL distributor it originaly came from. Below are some photos. I believe somebody more careful and patient can do a better job here.

Tue Feb 15, 2011 5:43 pm

Those not being distributors for US models, I've never seen either of them. However I do have some specs, and I thought the 111-AA distributor was supposed to be timed statically to TDC. Have you verified your total advance isn't too high?

Wed Feb 16, 2011 7:52 am

Quote: Those not being distributors for US models, I've never seen either of them. However I do have some specs, and I thought the 111-AA distributor was supposed to be timed statically to TDC. Have you verified your total advance isn't too high?

No, sorry I haven't, I'll need a timing light and a scale. However I did some tests with 10, 7.5 and 0 degrees timing. It turns out that it idles very smooth and easy at 0 deg static, but it lacks power when driving (quite noticable). At 7.5 deg static it idles a bit faster with the engine warm, the power is quite satisfactory when driving. However it idles faster and "heavier" while the choke is on, compared to 0 deg timing. At 10 deg advance static personaly I was not able to feel increase in power when driving, so I got it back to 7.5 deg.

I run the replacement vacuum canister I bought couple of years ago (a used one), it has a starlike pattern on the back side and no number on the rod (the right one is the original for 111--AA, it has 095 stamped).

Being curious about the dimensions, I have to say I found some differences between the both of them (as precise as I was able to measure). The notch near the diaphragm on the star-pattern one is about 6 mm unlike 7 mm on the 095. Also, the distance from the diaphragm disc and the hole where the rod attaches to the breaker plate is 51 mm, unlike 52.5 mm for 095. Considering that the metal the canisters are made of is about 0.8 to 1 mm thick, it turns out that the total amount of movement of the rod is 5mm and 6 mm for the "starlike" and the 095 canister, respactively. Converted to degrees at the carnkshaft pulley it is about 28.6 deg of advance produced by the "starlike" canister. For the 095 canister it is 34.4 degrees. Following this logic I completely agree with glutamodo that the 111 905 205AA distributor should be timed at TDC. This also complies with the data given here: http://www.oldvolkshome.com/ignition.htm#A6667. Now I see I did something wrong when assembling the 095 canister :). The other thing is that if the max advance is up to 35 deg BTDC for my engine (D letter code, 1.2 l), it turns out that when using the "star-pattern" canister (28 deg advance) , I need to time the distributor at 7.5 deg BTDC static in order to achieve the 35 deg at 3800 rpm (7.5 + 28.6 = 36.1). Indeed, when the distributor is timed at 7.5 deg static, I get the "usual" engine power (the "amazing" 34 hp@3600 rpm :) ) and quite satisfactory transitions when accelerating. However the idle is a bit higher (according to some specs it should be 750 to 900rpm), especialy when the choke is on. As for some specs and data I find the link below useful (it's in german):
http://www.vw-classicparts.de/repleitfaden_typ1_85/repleitfaden_typ1_85_seiten_9_78.pdf
also more general
http://www.vw-classicparts.de/

BTW, a bit of the topic here so I will be very short: the distributor drive slot is not perpendicular to the case split line when the pulley is at TDC, it's perpendicular at 10 deg BTDC.
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Wed Feb 16, 2011 11:45 am

Yeah, the star pattern, from discussion earlier in this thread that would likely be a 07017/1237121210 canister, and I've only ever seen one of those with the arm marked on it and that is timed to TDC. I'd posted that photo but I guess it was in a different thread. Several distributors used that vacuum canister (not yours though) and it was a Type 3 distributor on which I found such a canister marked 210:

The big problem with that OldVolksHome site is all those "can use" listings - making it seem all the parts on those distributors are totally interchangable. In many cases they may be, or they may fit, but they may not be quite correct when you do so.

That online VW manual - yeah, I've seen it and referred to it more than once. It's more of the technical bulletins that have been of interest to me, the ones that list the specific carbs and the specific distributors matched to them. For years I've been seeking those out and been doing charts based on what they say. There's a handful up to the late 60s archvied on TheSamba, some of those I had copies of myself at one point. Recently I got a huge boost in this regard from a bunch of early 70s tech bulletins I found online, plus I gained a collaborator from Australia who has tons of these in hard copy. I just put up the latest version of the DOC file with all this data:

https://www.thesamba.com/vw/archives/info/glutamodo/temp/CarbBaseFlangeNumbersA.doc

At the bottom of that document, I ask if anyone knows of more sources to let me know - to this day, no one has. I've had to dig all that info up myself. Then many months ago, I discovered Andrew P had some such info after doing some internet searching, and contacted him. I thought he might just scan some of his documents and let me figure what data was useful, but he went several steps further by filling in many of the question marks and blanks on my chart. Then just recently I found this archive of German-language tech bulletins totally by luck - I was Googling a distributor number and got a match for a base-flange number I'd never seen before in the process. Much of the data that Andrew had added was listed there too, plus several more entries I'd never seen before, which I plugged in what I could, and then he went and filled in some of the blanks. He says he's got even more non-US data to add as well, eventually.

What 30PICT-3 do you have? According to the info I've got, as soon on that chart, the VW1200s with a 30PICT-3 and BEFORE they switched to SVDA (1971-late 74) with the 111-AA distributor had the base-flange numbers in the VW283 VW284 and VW320 series. It was because of that info that I added the distributor numbers to this chart:

The slot in that drive gear - typical. They are never exactly perpendicular like the manuals show. Well, they are at one point as you drop them in place, but.. the spiral shape of the gearing makes it so that once it engages it is a little bit off.

Thu Feb 17, 2011 4:32 am

Quote: What 30PICT-3 do you have?

It's VW320-3 on the base flange. The car was purchased June 1973, which means (I think) 1972 model year. The engine number is D1061760.

The main jet is x112.5; air correction jet 170z (not 170w as in the doc table); idle jet g55; aux fuel jet g40; Oilbath air filter with 50 mm prewarm tube, flap regulated wia bowden cable connected to the thermostat. According to the info in the doc table it is European 1200 from eng D0675001, and from the small table, the timing should be at TDC.

Thu Feb 17, 2011 7:26 am

Do not mix the big and the small canister, the carb and the behaviour are very different.

The big canister is for vacuum only advance, so the advance has to increase with speed. If you look at a 30pict3 carb for this kind of advance, you can notice a small brass tube between the starter valve and the throttle valve.

The small canister is for vacuum+centrifugal advance; if you look at the same carburetor but in the SVDA configuration, the brass tube I told before is not present. The behaviour is different at all! In this configuration, the canister is only to achieve some additional advance when the gas pedal is partialized, and its function is a sort of 'on-off'. The rest of the advance is obtained by the centrifugal masses.

So, the small canister, is:
- off at idle
- on only with gas pedal slightly depressed
- off at 40% and over throttle opening

Don't mess with a wrong mix carb-canister!

Thu Feb 17, 2011 11:32 am

tasb,
Quote: Vac can # 015 used on the big cap 40 hp cast iron distributors ZV PAU 4R: 2,4,5,6. Large can with two mounting holes on the left side of the can. Mates to the 28 PICT and 28 PICT 1 carburetors. 40 hp.

I've got 2 screws on the left and one on the right, but my line comes out at the 9 O'Clock postiion that Everett mentioned.

Everett
"I've looked at quite a few big cap distributors and none have a vacuum can where the vacuum connection comes out at 9'oclock like that"

They are all like your other photo where it comes out more like 10:30:

Do I have the wrong canister on here?

Thu Feb 17, 2011 2:06 pm

herbie1200 wrote:

Don't mess with a wrong mix carb-canister!

And that's a big reason I've been assembling that large chart of modification state (base flange) numbers - all 30PICT-3s on 1200 after June 1974 were set up for SVDA and I think I have most of them listed now.

-Andy

Thu Feb 17, 2011 3:49 pm

Harris wrote: tasb,
Quote: Vac can # 015 used on the big cap 40 hp cast iron distributors ZV PAU 4R: 2,4,5,6. Large can with two mounting holes on the left side of the can. Mates to the 28 PICT and 28 PICT 1 carburetors. 40 hp.

I've got 2 screws on the left and one on the right, but my line comes out at the 9 O'Clock postiion that Everett mentioned.

Everett
"I've looked at quite a few big cap distributors and none have a vacuum can where the vacuum connection comes out at 9'oclock like that"

They are all like your other photo where it comes out more like 10:30:

Do I have the wrong canister on here?

I am wondering the same thing.Mine looks the same as yours.

Thu Feb 17, 2011 5:25 pm

herbie1200 wrote: Do not mix the big and the small canister, the carb and the behaviour are very different.

The big canister is for vacuum only advance, so the advance has to increase with speed. If you look at a 30pict3 carb for this kind of advance, you can notice a small brass tube between the starter valve and the throttle valve.

The small canister is for vacuum+centrifugal advance; if you look at the same carburetor but in the SVDA configuration, the brass tube I told before is not present. The behaviour is different at all! In this configuration, the canister is only to achieve some additional advance when the gas pedal is partialized, and its function is a sort of 'on-off'. The rest of the advance is obtained by the centrifugal masses.

So, the small canister, is:
- off at idle
- on only with gas pedal slightly depressed
- off at 40% and over throttle opening

Don't mess with a wrong mix carb-canister!

No, I will not mix them. The small one is from an SVDA distributor (a used one) I've bought some time ago. I believe that it will be very difficult to mount a small vac can on a 111 905 205AA distributor because of the following reasons:
1. From the pictures I've posted previously, there is a difference in the lenght of the diaphragm rods, the "095" rod is 52.5 mm, and the "461" rod is 42.5. It's 10 mm of difference, and I believe it would not be possible to mount it. Even if it's possible, 10 mm of displacement of the rod will cause about 57 degrees of advance on the pulley, and I don't think the pistons will be able to last very long that way. :lol:
2. The notch near the diaphragm is 7 mm for "095", and 2.5 mm for "461", so there will be almost no advance for the vacuum only distributor,
3. The mounting holes on the canister bracket are on different places relative to the diaphragm rod, so this is another reason why it wouldn't be possible to mix the canisters.
As for the vacuum advance channels in the 30pict3 vw320-3 carb, there are two openings, the lower one is near the trottle plate and it's load sensitive (for ex. climbing a hill, low rpm), the upper one near the discharge arm is speed sensitive (as when coasting at 100km/h, high rpm).
An yes, you are right, there are 30pict3 carbs intended to run with SVDA disributors, they do not have the upper orifice, the one near the discharge arm. I even have one such carb, the flange mod number begins with VW4... (sorry, I don't remeber the whole number by heart). It was intended to be run with paper element air filter (I bought it mounted on the paper air filter). Anyway, thank you very much for the advice, it got me thinking about what I've written. Thanks again.