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More Carby Questions 31PICt-3 - No idle

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Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 ·

#834978
Does the hole in the butterfly plate have to be blocked the same as a 34PICT-3???

It never needed to be on my 1300, but at this point I'm willing to try anything.


Smiley 😎
If you said I was a Volkswagen man, you'd be right.

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 ·

#834982
Ok. Here's all the info.

Engine is a 1600 Twinport AD case.

Valves have been checked and are set to .006"
Plugs are new gapped to 0.028"
Leads are new.
Coil is a red GT40
Distributor is a stock 009.
Running electronic ignition.
Timing is set to 10° at idle and 32° at full advance.

Carby is a 31PICT-3 with
Main - 135
Idle - 55
Power Correction - 60
Air Correction - 110Z

Choke is not operational so I've set it to stay open.
Fuel cutoff solenoid is connected and working correctly, have checked with the engine off and while running.

Have triple checked the manifold and carby for vacuum leaks, there are none.

Engine starts and runs, but only if you hold the throttle. Otherwise it just stalls. Acts like the cutoff solenoid is not functioning, just stalls out.


Can ANYONE suggest anything else that it could be before I burn it to the ground??


Smiley 😬
If you said I was a Volkswagen man, you'd be right.

Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 ·

#834986
Silly question but are you dead sure it's fuel?

could be weak spark, especially with a GT40 door stop.
I've had one do the same thing, I swore it was a carb problem, rough/no idle but swapped the GT40 for aother coil bam problem gone.

got another coil to try?

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

11,654 posts · joined Aug 2002 ·

#834989
Hi
sounds like the idle jet is blocked...
or can be the coil as Joel suggested..
are You sure the idle electromagnetic cutoff valve is actually NOT stuck closed..???

LEE

PS: check the High tension lead to the coil.... silicone ones can break VERY easily.....
try a VW wire HT lead in to check if You are getting all the spark... wire leads don't break..

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

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 ·

#835002
Joel wrote:Silly question but are you dead sure it's fuel?

could be weak spark, especially with a GT40 door stop.
I've had one do the same thing, I swore it was a carb problem, rough/no idle but swapped the GT40 for aother coil bam problem gone.

got another coil to try?
Tried a different coil. No difference to problem.

68AutoBug wrote:Hi
sounds like the idle jet is blocked...
or can be the coil as Joel suggested..
are You sure the idle electromagnetic cutoff valve is actually NOT stuck closed..???

LEE

PS: check the High tension lead to the coil.... silicone ones can break VERY easily.....
try a VW wire HT lead in to check if You are getting all the spark... wire leads don't break..
Cutoff solenoid is operating as it should, I'm sure.

All the leads are brand new, I bought them this morning.


Any more brain busters?

The only other thing that I can think of is the electronic ignition. About to throw the points back in it and try.


Smiley 😎
If you said I was a Volkswagen man, you'd be right.

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 ·

#835003
Joel wrote:could be weak spark, especially with a GT40 door stop.
Why are these no good?

It's not one of the crappy round ones.

It's one of these





Smiley 😎
If you said I was a Volkswagen man, you'd be right.

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 ·

#835008
Points made no difference. 😬😬



Smiley 😬
If you said I was a Volkswagen man, you'd be right.

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

11,654 posts · joined Aug 2002 ·

#835010
Smiley wrote:Does the hole in the butterfly plate have to be blocked the same as a 34PICT-3???

It never needed to be on my 1300, but at this point I'm willing to try anything.


Smiley 😎
No...

I don't think that would fix this problem..

You haven't put any OLD fuel into Your tank???
Fuel doesn't last long these days before going off...
and causing problems..

have You tried adjusting the timing??

LEE

LEE written at 2pm..
- 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 ·

#835017
Smiley wrote:
Joel wrote:could be weak spark, especially with a GT40 door stop.
Why are these no good?

It's not one of the crappy round ones.

It's one of these
....................................................................................

Hi
the points should be GB534 ?

The round coils are oil filled for cooling....
GT40 s have a lower resistance than the other Bosch coils..
round ones.. nothing wrong with the round ones either,,,
IMHO..

I Hope You find the problem...

did you clean the points before using them with petrol or alcohol etc.. they do have a protective coating on them.
Condensor OK... they should be replaced every year or so...


You have the coil connected the correct way... many people
who have owned VWs for many years still get them mixed up at times.. I always check 3 times.... lol

I bought a beetle a few years ago that stopped at every intersection.. [foot off pedal]
I took it home and tuned it up..
and no problems after that...
its probably something easy?? once You find it...

cheers

LEE

PS: sometimes New parts aren't as good as the old parts..
the old parts have been tested and DO work... lol













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

Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 ·

#835042
GT40 coils just seem to have high fail rate, I;ve had 2 die on me, a couple of freinds the same and just the cases I;ve read on forums.

Overall consensus seems to be the solid state ones you bought at the worst but give it try, I always had a spare coil under the back seat in my bugs.

I would be checking the resistance of it though, most electronic ignitions are very fussy on what the resistance is, 99% of VW kits are designed for 3ohm coils.


Also as Lee mentioned 529 points are designed for the late twin port dissys with the shorty cap (73-76).
the early ones and all 009s use 534 points.

BRUTUS Officially Full-On Dubber

255 posts · joined Feb 2006 ·

#835093
Smiley,
I had a 1600 bug with a 34PICT-4 that had similar symptoms. It all worked/checked out well, except it would NOT idle. I cleaned it out, dismantled everything, etc., but still the same. The idle mix screw and the bypass screw were not doing anything. Then I got Really Annoyed and with the engine running fast (well above idle), removed the idle MIXTURE SCREW, then revved it hard while squirting carb cleaner (using spray can with small plastic tube) in the hole. Then put back MIX SCREW; then removed the (large) bypass screw, with the engine running, then squirted in cleaner as before. It fixed it. (Didn't remove the idle JET, but that might have been next.) There was obviously a blockage that couldn't be got at or seen... Take care...
ACE 30 & 40 oils: specifically engineered for your Air Cooled VW
delivered (free del.) throughout Yarra Valley / Ranges, & Gippsland areas. Also ACE 20, 50 & 90.
FOR SALE: ACE 30, 40 etc. Oil formulations & Trade-names.

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 ·

#835391
68AutoBug wrote:
Smiley wrote:Does the hole in the butterfly plate have to be blocked the same as a 34PICT-3???

It never needed to be on my 1300, but at this point I'm willing to try anything.


Smiley 😎
No...

I don't think that would fix this problem..

You haven't put any OLD fuel into Your tank???
Fuel doesn't last long these days before going off...
and causing problems..

have You tried adjusting the timing??

LEE

LEE written at 2pm..
I drive the car everyday, if the fuel has gone of in 3 days I'd be worried!!


Smiley 😎
If you said I was a Volkswagen man, you'd be right.

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 ·

#835392
Joel wrote:GT40 coils just seem to have high fail rate, I;ve had 2 die on me, a couple of freinds the same and just the cases I;ve read on forums.

Overall consensus seems to be the solid state ones you bought at the worst but give it try, I always had a spare coil under the back seat in my bugs.

I would be checking the resistance of it though, most electronic ignitions are very fussy on what the resistance is, 99% of VW kits are designed for 3ohm coils.


Also as Lee mentioned 529 points are designed for the late twin port dissys with the shorty cap (73-76).
the early ones and all 009s use 534 points.
That's just an old picture, the only one I have of the coil, back when I had a vac dizzy, that's what the points are for.

I did try a different coil, and it made no difference at all.

If the GT40 coils are no good what SHOULD I be running? Cause I will just go and buy one.
Was thinking of getting a Pentronix set of electronic points and matching coil. Is this a worthwhile investment?


Smiley 😎
If you said I was a Volkswagen man, you'd be right.

Smiley Veteran Volks Folk

2,125 posts · joined Oct 2008 ·

#835395
BRUTUS wrote:Smiley,
I had a 1600 bug with a 34PICT-4 that had similar symptoms. It all worked/checked out well, except it would NOT idle. I cleaned it out, dismantled everything, etc., but still the same. The idle mix screw and the bypass screw were not doing anything. Then I got Really Annoyed and with the engine running fast (above idle), removed the idle jet, then revved it hard while squirting carb cleaner (using spray can with small plastic tube) in the hole. Then put back jet; then removed the (large) bypass screw, with the engine running, then squirted in cleaner as before. It fixed it. (Didn't remove the idle mix screw, but that might have been next.) There was obviously a blockage that couldn't be got or seen... Take care...
I will try this next chance I get.

Will it run if I pull the jets out?



Smiley 😎
If you said I was a Volkswagen man, you'd be right.

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

11,654 posts · joined Aug 2002 ·

#835409
Smiley wrote:
Joel wrote:GT40 coils just seem to have high fail rate, I;ve had 2 die on me, a couple of freinds the same and just the cases I;ve read on forums.

Overall consensus seems to be the solid state ones you bought at the worst but give it try, I always had a spare coil under the back seat in my bugs.

I would be checking the resistance of it though, most electronic ignitions are very fussy on what the resistance is, 99% of VW kits are designed for 3ohm coils.


Also as Lee mentioned 529 points are designed for the late twin port dissys with the shorty cap (73-76).
the early ones and all 009s use 534 points.
That's just an old picture, the only one I have of the coil, back when I had a vac dizzy, that's what the points are for.

I did try a different coil, and it made no difference at all.

If the GT40 coils are no good what SHOULD I be running? Cause I will just go and buy one.
Was thinking of getting a Pentronix set of electronic points and matching coil. Is this a worthwhile investment?


Smiley 😎
i BELIEVE THE PERTRONIX IS Great and well worth the money..
You will need a HIGH Resistance coil...
which is really just a standard coil..
[to fit what????} I just got people [on ebay] to measure the resistance in Ohms of the coils they had for sale...
The answer will be approximate unless they have a really good multimeter...
so a 3 ohm coil May measure 2 ohms or 4 ohms ???
but many measure BELOW 1 ohm.... which isn't good for Pertronix.. or some other ignition systems..

LEE

PS: Good to know what You were doing with those points etc...
- Helping keep Air Cooled VWs on the road - location: SCONE in the Upper Hunter Valley - Northern NSW 320 kms NNW of SYDNEY---

Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 ·

#835423
Smiley wrote:
Joel wrote:GT40 coils just seem to have high fail rate, I;ve had 2 die on me, a couple of freinds the same and just the cases I;ve read on forums.

Overall consensus seems to be the solid state ones you bought at the worst but give it try, I always had a spare coil under the back seat in my bugs.

I would be checking the resistance of it though, most electronic ignitions are very fussy on what the resistance is, 99% of VW kits are designed for 3ohm coils.


Also as Lee mentioned 529 points are designed for the late twin port dissys with the shorty cap (73-76).
the early ones and all 009s use 534 points.
That's just an old picture, the only one I have of the coil, back when I had a vac dizzy, that's what the points are for.

I did try a different coil, and it made no difference at all.

If the GT40 coils are no good what SHOULD I be running? Cause I will just go and buy one.
Was thinking of getting a Pentronix set of electronic points and matching coil. Is this a worthwhile investment?


Smiley 😎
It seems to be luck of the draw with GT40 coils, with all the failures I mentioned there are the exceptions, dads has been on for 10 years now, bought the same time as mine in 2001.
his is still going, mine died in 2005

Although died isnt the right word as it still operated but was doing what you are experiencing.
Would make it run ok at revs but would barely idle roughly or not at all.

Had me puzzled why it ran fine at revs especially under load though which is why I didnt suspect a dud coil it at first.

The other I had die on me was in my Celica, it would cut out when it got hot then would restart after 15 mins of cooling down, run for a bit......rinse and repeat.

As to what to run, piece of string type question.
people rave about Bosch blue for VWs, never used one myself
If pertronix make their coils as good as their electronic ignitions I'd be going for it.

I've had a couple of Hanshin coils which came on bugs I've owned which I suspect were probably OEM coils off jap cars which worked well.

BRUTUS Officially Full-On Dubber

255 posts · joined Feb 2006 ·

#835483
Sorry Smiley, mixed up the Mixture Screw and the Idle Jet. Have corrected text (in capitals) in original post. The problem was apparently behind one of the 2 screws. I don't think I removed the jet, but it was a long time ago, so not sure. I kept the revs up (may have propped open the throttle lever; and removed screws quickly, spray can at the ready... revved it hard when spraying in. It made plenty of fumes.
ACE 30 & 40 oils: specifically engineered for your Air Cooled VW
delivered (free del.) throughout Yarra Valley / Ranges, & Gippsland areas. Also ACE 20, 50 & 90.
FOR SALE: ACE 30, 40 etc. Oil formulations & Trade-names.