Here we go again...

This is about flat spot.


I had a 1972 AB 1300DB engine with a 31 Pict 3 carb with flat spot.

I rebuild it with new 1600 pistons and cylinders. The Heads were open to 1600.

Everything is sock inside the case.

I have the same distributor 113-905-205AL. This distributor was also used on US
on a 1600DP engine with manual transmission as mine. It is a SVDA.

I changed the manifold and the carb to a 34 Pict-3 (I don’t know the size of the
jets)

Do I have an AD engine? I don’t know want type of engine I now have and I would
like to have our opinion on this to set the timing.

I asked the opinion to a mechanic that worked on the VW dealer here where I live
for 30 years and worked on my car for more than 15 years and he knows it very well
and he told me that I should set the V notch mark on the case split to avoid a hole
on a piston, because I still have a flat spot from the idle. This should be a static
set-up. When I told him that I changed the pistons and the carb we told me that
now I have to mess with the jets to end with the flat spot.

If it is an AD with SVDA the V notch should be set 7º BTDC at 800-900 rmp with stroboscope
and then I have to mess with the jets until I end with the flat spot. Is this correct?

Any suggestion on the jets sizes?






Joao

72 Super 1302

I have to find the problem...

If I have a flat spot with a SVDA it must be because the vacuum can is not working
properly. I do believe it is not the original so I order a new one from Bosch. When
sucking the ar from it I can feel that the membrane isn’t stressed, because I can
hear it, so the vacuum advance will always response with a delay causing the flat
spot.
Do you think that this make any sense?

I can't find the correct Bosch part number of the vacuum can for my distributor
in the internet.

113-905-205AL VW
0231-146-101 BOSCH

Joao

72 Super 1302

"Joao Eliseu" > wrote in message >...
> I have to find the problem...
>
> If I have a flat spot with a SVDA it must be because the vacuum can is not working
> properly. >
> 113-905-205AL VW
> 0231-146-101 BOSCH
>
> Joao
>
> 72 Super 1302

Joao,

Try sucking on the vacuum line with the distibutor top off - you
should be able to see the points plate moving with the suction - if it
doesn't (or it moves but then drifts back when you cover the vac line
with your tongue) then the canister diaphragm is leaking.

You should be able to get vacuum canister and/or componenets from
www.aircooled.net - email John on if you can't find
what you want on his site.

For a 1600 with 31PICT/3 (or the modern reaplcement carb for it - the
H30/31), try using a 55 idle jet (right side of the carb - closest
brass jet to the float bowl) 125 (or just possibly a 127.5) main jet
(bottom of the float bowl) and a 125 or 130 air correction jet (take
the top off the carby to find it - a vertcial brass screw head between
the float bowl and the main throat - careful as it's about an inch
long - has the emulsion tube attched underneath). The other jet in
the right side (angled) is the power jet - should be a 65. This one
only works at high power high rpm.

The correct timing for your combo of 1600 and single vacuum
distrtibutor is 7.5BTDC. Make sure you KNOW what that timing notch on
the pulley is. If there is only one notch and no dimple on the other
rim just to the left of the notch then it's a 5ATDC notch with is used
with the double vacuum distiburos to set 5ATDC at idle. Using this
with a single vac distributor would result in 12.5 degrees of
underadvance - the car will lack power, overheat and have the
stumbles.

How do you check the notch? Put a pencil or straw down No1 (right
front) plug hole and feel for the piston top - get the piston as high
as it will go and then look at the timing mark near the top of the
pulley. If it's to the left of the crankcase split - it is indeed a
5ATDC notch and you need to make a new mark 11mm to the right for TDC
and 18mm to the right of that original notch for 7.5BTDC.

If you have a pulley with one notch and a dimple on the other rim (to
the left of the notch), the dimple is TDC and the one notch is
7.5BTDC.

Timing can be set static, or at idle with a timing light and the vac
line removed from the carby and plugged, so there's no chance of the
carby vacuum spoiling the setting. Don't forget to reinstall the vac
line after the adjustment.

Regards
Rob
Rob and Dave's aircooled VW pages
Repairs and maintenance for the home mechanic
htpp://www.vw-resource.com

>If you have a pulley with one notch and a dimple on the other rim (to
>the left of the notch), the dimple is TDC and the one notch is
>7.5BTDC.
>

This is what I have...and that is why the mechanic I spoke with told me that… He
knew that I have that dimple (TDC) on the rim and he smiling when he told me that.

I have read you web page a lot of times and I never saw anything relayed with this
dimple on the rim. I will check it right now.

Thanks very much

Joao

72 Super 1302

I’m so hungry with myself. I can’t understand how I could I miss that. After read
your post I open the Haynes on page 72 and here it is:"see also that the V notch
in the crankshaft puller wheel is clean and visible (...).The notch should line
up with the crankcase joint."
I do believe that many engines are working at 15º BTDC instead 7.5º BTDC, because
many people think that the V notch indicates the TDC.
Since Ingles is not my first languish I can easily miss something and this was one
of that situations.
This was unbelievable...

Joao

72 Super 1302

On 20 Mar 2005 14:03:56 -0800, "Joao Eliseu"
> wrote:

>
>I’m so hungry with myself.

*holds up index finger with puzzled/questioning look on face*

> I can’t understand how I could I miss that. After read
>your post I open the Haynes on page 72 and here it is:"see also that the V notch
>in the crankshaft puller wheel is clean and visible (...).The notch should line
>up with the crankcase joint."
>I do believe that many engines are working at 15º BTDC instead 7.5º BTDC, because
>many people think that the V notch indicates the TDC.
>Since Ingles is not my first languish I can easily miss something and this was one
>of that situations.

Usted habla ingles mas bueno que yo habla espanol. :-)

>This was unbelievable...
>
>Joao
>
>72 Super 1302


---
"There's nothing wrong with a little shooting as long as the right people get shot."
- Inspector Harry Callahan

Shag wrote:
> On 20 Mar 2005 14:03:56 -0800, "Joao Eliseu"
> > wrote:
>
>
>>I’m so hungry with myself.
>
>
> *holds up index finger with puzzled/questioning look on face*
>
>
>>I can’t understand how I could I miss that. After read
>>your post I open the Haynes on page 72 and here it is:"see also that the V notch
>>in the crankshaft puller wheel is clean and visible (...).The notch should line
>>up with the crankcase joint."
>>I do believe that many engines are working at 15º BTDC instead 7.5º BTDC, because
>>many people think that the V notch indicates the TDC.
>>Since Ingles is not my first languish I can easily miss something and this was one
>>of that situations.
>
>
> Usted habla ingles mas bueno que yo habla espanol. :-)
>
>
>>This was unbelievable...
>>
>>Joao
>>
>>72 Super 1302
>
>
>
> ---
> "There's nothing wrong with a little shooting as long as the right people get shot."
> - Inspector Harry Callahan


You where not the only one darling...

J. :O]

>
>Usted habla ingles mas bueno que yo habla espanol. :-)
>

Hola Shag,

Mira, también entiendo un poquito de Español e Portugues.

Saludo
Joao

Joao

72 Super 1302

Joao Eliseu wrote:
>
> >
> >Usted habla ingles mas bueno que yo habla espanol. :-)
> >
>
> Hola Shag,
>
> Mira, también entiendo un poquito de Español e Portugues.
>
> Saludo
> Joao
>
> Joao
>
> 72 Super 1302

Ay Carambola

I used to date a girl named Mira once. hehe.

Jan