blowing black smoke?

72super Casual Dubber

35 posts · joined Jun 2006 · 27 Jun 2006, 12:18 pm

#505451

Have a 72 superbug that when it is revved hard it blows some black smoke. Have been told it may be running a bit rich. However when it is revved up slowly it is Ok, only if it gets a gutful. How do I adjust the mixture? etc all help taken

EgeWorks Wolfsburg Wizard

602 posts · joined Jan 2004 · 27 Jun 2006, 12:52 pm

#505455

What sort of carburettor(s) does it have?

72super Casual Dubber

35 posts · joined Jun 2006 · 27 Jun 2006, 1:45 pm

#505475

solex pict 34 on a 1600tp

[ Edited on 27-6-2006 by 72super ]

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 27 Jun 2006, 2:17 pm

#505483

Hi,
It sounds like the Accelerator pump on the carburetor is doing its job....
The harder You press the pedal...
the more fuel it pumps in...
otherwise You would have a dead spot....
A rich exhaust is good for Air Cooled VWs...
A Lean exhaust spells trouble for an air cooled VW...

I wouldn't be concerned....
My Beetle and My Sons are both running rich and the exhausts are sooty....
At least We know the valves aren't going to drop off ,due to a lean mixture...

cheers

Lee 68AutoBug

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

72super Casual Dubber

35 posts · joined Jun 2006 · 27 Jun 2006, 2:34 pm

#505488

lee. when you rev harshly it HAS got a dead spot

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 27 Jun 2006, 2:53 pm

#505491

Are You running a 009 distributor...??
as 009s are crappy compared to a Vacuum/centrifugal advance distributor..
The 009s relies only on the centrifugal mechanical advance and its just not quick enough...

with the original VW type dizzy, the vacuum cuts in as soon as You hit the throttle
and advances the ignition timing...

also 009s Have to be timed at 32 degrees approx with the engine running at maximum advance...

cheers
Lee

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 27 Jun 2006, 2:57 pm

#505493

If You are running a standard distributor...
then apart from the ignition timing...
Your Solex could be running too rich at Idle....
so the fuel mixture IS too rich when You hit the throttle..

Lee

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

CHADMYSTER Seriously Crusin Dubber

171 posts · joined May 2004 · 27 Jun 2006, 6:28 pm

#505549

standard distributer, which screw to adjust for mixture?. (72 super at work/ chadmyster at home!)

Bizarre Moderator The artist formerly known as blue74l

12,785 posts · joined Aug 2002 · 27 Jun 2006, 7:37 pm

#505582

http://www.vw-resource.com/34pict3.html

read here

Futue te ipsum!!!

72super Casual Dubber

35 posts · joined Jun 2006 · 28 Jun 2006, 7:25 am

#505810

thanks

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 28 Jun 2006, 7:37 am

#505813

Yes, Rob & Dave know their stuff....

I didn't realise the 34 PICT 3 was so complicated to tune..

Lee

- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

72super Casual Dubber

35 posts · joined Jun 2006 · 28 Jun 2006, 8:58 am

#505831

yes i have printed out instuctions. will see how i go