Retrovans 1972 Panel Van low light Bay

[retrovan]

OK I have been able to get the numbers off the Dizzy and they as follows;-
Z414
0 237 023 007
071 905 205

Anybody know what its originally off and what year it is. ??

Thanks for your Time

Herman

[retrovan]

So had a look on The Samba, and as far as I can find out the dizzy is for a late 2lt aircooled type 4.

But this is also what I found ;-
The Bosch 0 237 023 007 is a DVDA distributor for an aircooled 2.0L Type4 engine.

Currently this dizzy is on a rebuild 2.0L Type 4 with duo Dellorto's 40 and ported/full flowed heads, CR 8.0:1, stock cam and VintageSpeed exhaust (in a heavy T3/T25/Vanagon Westy). It performs well but I think it's limiting the potential of the engine. (Almost flat torque curve starting at 125NM at idle, with a max of 145NM between 2500 and 3500 rpm, falling back to 125NM at 4750 rpm. I was expecting somewhere around 160-165NM. HP's are not that imortant but are around 82 DIN HP.)

This seams to be what I am getting.

Runs OK but not what she was before the cam issue.

What now, do I run her in and see later or try to fiddle with the dizzys I have got, One at a time ????

Herman

[sean]

Hi Herman

There is no power difference between the points distributor to the electronic one. Many think that converting to electronic ignition is bolt on power, which is not so. You do however have a stronger spark and a more constant/accurate timing.

What to check:

I assume you havn't utilised the vacuum retard? This would effect power. Only the later distributors had these. Don't use the vacuum retard.

Have you checked the electronic distributor is advancing correctly? It may have a sticking mechanical advance or leaking canister which your old one didn't.

[Tony Z]

Runs OK but not what she was before the cam issue.

What now, do I run her in and see later or try to fiddle with the dizzys I have got, One at a time ????

Herman

Thats What I did, then connected the vacuum again and re-strobed it again, finding that she went over max advance, so I brought her back as said....

Herman

your lack of power may be because you set your timing without the vac hose, as you should, then connected up, rechecked and reset with the hose connected...
set it without the hose, then dont worry about what happens when the hose is on

[retrovan]

....... Don't use the vacuum retard.......

No have not used it, have just let her breath naturally.

[retrovan]

.......
Have you checked the electronic distributor is advancing correctly? It may have a sticking mechanical advance or leaking canister which your old one didn't.

Yes thanks Sean, Have run her with the strobe light and monitored her on centrifugal advance only as well as with vacuum advance, both seem to work smoothly and evenly.

Engine guru feels it lack of settlement and I should give it time, and run it hard to seat all again. ???

Will run her like this for a few Km and then try setting her at max advance without vacuum as Tony has said and fit vacuum again without back adjustment and test her again, just do not want her to ping.

Herman

[retrovan]

Having read the Samba guys findings and finding the same on my engine, I am sure this dizzy was curved for the more heavy body and running load.

Will run for a time and then fit the original dizzy this engine had on when she ran like hell, and report back.

could this be ????

Herman

[Dawie]

Total centrifugal advance from 2L "CU" aircooled engine is 22.5 degs, static/idle at 7.5 deg. Similar to CJ 2L.
So total at max rpm, vacuum disconnected, is 30 degs. That was when using 91Ron octane fuel at coastal altitude. (Vw's spec for a lower octane fuel which was used some places at the time.) Still used in Usa, but called "87 octane" there, or ron/mon. Us 91 "high octane" probably closer to our 95ron.
We used to have 87ron in highfeld areas, but that was much lower than usa 87ron/mon.

[retrovan]

Thank you @Dawie, so what you say is set it to 30 with vacuum off, and do not bother where it is with vacuum fitted. even if she runs over 35 ?

Herman

[Dawie]

Correct. After timing is set, vacuum advance, when connected, is supposed to add to centrifugal timing degrees.

[retrovan]

Thanks Dawie, will give it a try

Thank You

Herman

[Haans]

Herman,....this that happened and is still happening just tells me that there is plenty more to learn ,...for me at least.

On a more lighter/humerous note,.......my late father told me,......run at 40k's in "top" nogal and if it pings,.....timing to be brought back a smidge...!! .......and it seems to work!,.....running the old goat at 7.5* and seem happy ,..unless I am too deaf to hear it ?

I am not advocating this as the end all,.......,....set it to where it is happy and run it!

Good luck. Haans

[Dawie]

Setting by "ear"... watercooled, (tightly controlled coldish head temperature, by thermostat,) yes. Only watercooleds.

Aircooled, especially if thermostat was removed...
(Temp now all over the place), head temp (not oil temp), fluctuating depending on load, when setting timing by ear when not at absolute max temp= destructive knocking later when at max head temperature.

Timing requirement varies with head temperature. Aircooled head's design operating temperature exceeds 200 degs at max power. Less advance timing is needed when hot, because less heat energy is then wasted towards heating of colder head/cylinder surfaces.

If we set timing by ear while at 85 degs, (7.5:1 compression engine, designed for 220deg max operating temp), setting may typically end up at 40 deg max rpm vacuum disconnected, or 17.5 static/idle rpm.

To properly set aircooled by ear, you would need someone in back of kombi with engine lid removed, (73 and later which have second lid inside above engine). Otherwise sitting on a platform above rear bumper. Then set timing by ear while driving at max power on a heatwave day, loong uphill, loaded with a trailer. Then still retard 2 deg from that to leave room for carbon build up conditions over time. Doing it this way, you will probably end up close to VW's spec.

[retrovan]

@Dawie, you got me thinking back to my childhood days now,... was little kid there for a moment, seeing my mom drive the old English car, we had a few , with my DAD sitting in the engine bay with the bonnet removed, trying to set timing "JUST RIGHT"

Running up and down the main street revving the out of the old Austin, or Morris just to get that extra few Miles per gallon out of the old girl.

You see my dad had to ride from the old Halfway House to JHB for work on the old Pretoria road, this took him nearly an hour in those days.

Not because of traffic but because of bad cars and bad roads.

Petrol was expensive at 2and 6 a gallon ( about 23 cent per 5 liters)

That was great memory's, thanks.

Herman

[retrovan]

So as I was sitting thinking that there must be a way to get this VW verses VW distributor issue sorted.....

Being an engineer, I decided that we will build the vacuum and centrifugal into the electronic Hall Effect dizzy.

Now deciding and doing is very different specially if the concept is done in the head and not on the work bench.

This morning reality struck, the two dizzy s are different lengths, and the shafts as well.

Thinking that that as both are for the type 4 2lt, VW surly would not have different centrifugal values, but would make adjustments with the vacuum coming in as you put your foot down in a heavy body bus, and maintain the correct timing that way.

Taking both dizzy s apart and testing the springs, I was sure I have surmised correctly, so went about servicing the dizzy and fitting the smaller vacuum can to the hall effect dizzy.

Well optimistic I fitted the dizzy, more or less at the right timing, and started her.

Must point out at this time, I do have twin 34 ICT Webers without choke on her, and starting a cold type 4 without choke and bad timing is not the greatest thing to do on a freezing cold day.

Long story short, got her to splutter till warmed up and ran off to the back , with timing light already connected I got the timing as per recommended ABOVE and let her warm up nicely., switched off, removed the timing light, rev meter, and re fitted the vacuum pipe.

Got in and swung the key and she took 1st turn.....

Rev ed her and HEY !!! PRESSTO !! that dead spot is gone......

Now I know the ICT naysayers where convinced its the carbs, but I had faith in the VW engineers of old that they had a plan for having so many different dizzy's over the years and over the same engines.

That means I now have the correct dizzy for the correct engine with the right curve but with the OEM electronic update.

So I may be happy prematurely, and still need to road test her, but why spoil a good day..

For the record I have now the 0 237 023 007 Bosch dizzy with Hall effect pick up and Golf electronic unit.
Fitted the small vacuum can from the 0 231 168 005 Bosch points and cap dizzy for the 2lt type 4.

Herman