34 PICT 3 re-build advice please....

[Oldman]

The solenoid shuts off the fuel to the idle circuit.

Ok, to clear up the confusion.....I hope !!

This is the solenoid/ air cut-off on the Solex 34 PICT 3 , as installed on this bus:

   

....and this is the solenoid/ fuel cut-off on other Solex , this type not on this bus:

   

I have learned that the function of the solenoid is carb. model specific and very different.

[grumble]

Sorry Gents, Type 1 1600 DP…..my son’s bus, Herman….no rubber elbows or fuel cutoff solenoid.
Big thank you to Barry for posting that link…..it certainly helped a lot.

Update…
Success….…
Pulled the carb off the bus this morning and stripped it back down.
(Gets quicker, the more you do it ……. )
Removed the redundant O rings and cleaned it all up again.
Also modified the top/bottom gasket as it wasn’t really a great fit, partially blocking galleries and offset on the securing screws…..much happier with the fit now.
I didn’t go down the BB route……. 
Reset the choke element to the factory marks on throttle body and choke element itself.

Spent 1/2 an hour chasing a 13 mm nut around the engine bay……..damn, having a top access hatch on my late bay saves time for this sort of stuff !



Well done Mate.
Carby reinstated I set the baseline on mixture and idle/air bypass……….and crossed thumbs.
Battery reconnected, turned the key and Herman kicked into life…..under choke.
Waited for the engine to warm up and…………it now holds idle off the choke cam !
Spent 10 min. or so fine adjusting mixture and idle and he’s purring nicely 

[Oldman]

Thanks Les, very happy with the result....
I thought it worth a shot to try and re-build before it was replaced, turned out well........and a lot cheaper, with the added bonus of a lot of learning gained along the way.
A very worthwhile exercise. 

[syncro]

Ok, to clear up the confusion.....I hope !!

This is the solenoid/ air cut-off on the Solex 34 PICT 3 , as installed on this bus:



....and this is the solenoid/ fuel cut-off on other Solex , this type not on this bus:



I have learned that the function of the solenoid is carb. model specific and very different.

No confusion. Dual port and single port. The type you have cuts off the fuel to the idle circuit. The other type is the actual jet that the solenoid closes.

[Oldman]

No confusion. Dual port and single port. The type you have cuts off the fuel to the idle circuit. The other type is the actual jet that the solenoid closes.

Happy to be educated but  I'm confused and tend to look for repeated references to the same thing for guidance....

From one pedant to another, ( and I mean that in a positive way ), why then is the part I'm using listed as an air cut off valve on the JK website and referred to as such in numerous articles...?
I know that the terminology blurs quite a bit depending on the article read....(particularly the individual jets).... but there is a consistency with this particular part.

Surely it would be in the seller's best interest to have the description correct....I wouldn't want to pay for a fuel cut off solenoid and be sent an air cut off solenoid.
Both are listed for the same year vehicle, but are Carb model dependent.
Heritage Parts also has its description as... " 12 volt carburettor air cut off valve. For 34 PICT-3 Carburettor " 
and further down......................................... " IDLE AIR BY PASS CUT OFF VALVE FOR 34 PICT-3 CARB 12V "

Could it be that this part cuts off the mixture of air and fuel in the idle circuit ?
That would make sense to me 

[syncro]

Since when do you believe the listings from JK or Heritage? They are both terrible. Heritage are the ones that I really hate dealing with. Arrogant bunch of halfwits.

[Oldman]

From ETKA :
Further reading shows the same part used on different Solex carbs.

Part #39 - By pass air cut-off valve for carburettor

OEM / VAG Part number - 049 129 412 C 
(same OEM number as listed on both JK and Heritage websites )

https://webautocats.com/etka/volkswagen/t2/29/014000/

[Doob]

In relation to the Electromagnetic cutoff valve as installed on single 34-PICT-3 carburetor. (such as on a 1971 1600cc dual port Kombi) 
See the attached scan form the Bentley Manual  Section 3 page 10 - figure 5-1 
Gives a summary of the function of this solenoid cutoff valve

  electromagnetic cutoff valve.pdf (Size: 76.09 KB / Downloads: 9)
  Scan_0195.pdf (Size: 487.88 KB / Downloads: 4)

[Oldman]

Great info !
So it DOES cut off the air and fuel mixture………..
(The answer was on my desk all the time....!)
Thanks 

[syncro]

Great info !
So it DOES cut off the air and fuel mixture………..
(The answer was on my desk all the time....!)
Thanks 

I knew that it cut off the fuel as it is wet when removed but did not know it was after it was mixed with air. Not that it matters. The engine still gets some air past the butterfly at idle.