Page 1 of 1

1.9DG with a Weber carb

Posted: 11 Mar 2021, 14:09
by pixelsandpasties
Hello! I have a 1987 1.9DG with what I thought was an upgraded Weber carb, not the stock Pierburg.

New to mechanics in general, I assumed it was an upgrade as I have heard of Weber carbs, but never Pierburg, prior to owning my DG. I've since been told a Weber is not necessarily an upgrade.

How can I be sure that the carb is running well and tuned, and is this something that you fine folks would recommend I have a go at myself?

I'm fairly mechanically competent, mostly changing parts and servicing. No experience of timing, fuel systems or anything like that.

I'm based in Carmarthen, and would be interested in any recommendations of locals who know these vans.

Re: 1.9DG with a Weber carb

Posted: 11 Mar 2021, 16:01
by Mocki
welcome , are sure it’s Weber , stick some pictures up so we can see what you are looking at
Image

Weber’s don’t suit WBX , some folks have spent loads of time and money and still can’t get them to run any good ....
 

Re: 1.9DG with a Weber carb

Posted: 11 Mar 2021, 16:05
by weimarbus
I have run my camper on both the original Pierburg and the Weber as a 1.9 DG and also with the current 2.1MV, I have a fuel/air ratio gauge with a lamda sensor and can confirm that the pierburg has a more sophisticated fuel delivery than the Weber but could not tell the difference either in driving experience or fuel consumption between the two. I appreciate that this is anecdotal evidence and others may disagree but the Weber is simpler to tune for tick over.

Re: 1.9DG with a Weber carb

Posted: 11 Mar 2021, 16:31
by hubcap61
Replaced the Pierburg on my DG motor with a 34 DAT Weber 7 years ago. I fitted a new gasket and needle valve kit. Spent a couple of days setting up the choke and tickover. Havent touched it since, starts every time, 1st turn, (daily driver) no issues at all. I personally prefer the simplicity of the Weber over the Pierburg.

1.9DG with a Weber carb

Posted: 11 Mar 2021, 18:21
by DoubleOSeven
Turn the air fuel mix screw until the revs are at their maximum, then adjust the idle to 850rpm. That’s it. Quite an art to do it by ear though. Only turn the mixture screw half at a time and then clear the engine by holding it at 2000rpm for 20 seconds after every adjustment. Personally I turn the air/fuel mix all the way in until it stops, then out 3 turns.

Clockwise Lean (lots of air)
Anti-Clockwise Rich (lots of fuel)

Ideally though you want to use a gas analyser to set your air/fuel mixture; so I’d recommend popping down your local MOT
place and ask to use theirs or indeed ask them to do it for you.

Nothing else to play with on a carb. really until you get into the realms of changing jets for improved performance.

You are trying to find the sweet spot between the dotted lines:

Image

However, carburettors are generally best left alone. Check your ignition timing though using the guide in the wiki, very simple and will probably give you better gains.

VW spent millions £ on research and development and decided the Pierburg 2E3 was best for the 1.9DG. I can only assume the Weber gets mentioned as a replacement due to a hangover from the air cooled lot. ie when their Solex and PICT carbs needed a refurbishment they just replaced them with the only carb on the shelf, a Weber.

Re: 1.9DG with a Weber carb

Posted: 11 Mar 2021, 20:33
by ash1293
I’ve a 1.9DG with a Weber 34Dat. When they were sold as a direct replacement the stock jetting doesn’t perform well at all, big flat spots and just generally not great,

Did a lot of reading, mainly from American sources but after changing jet sizes it now pulls really well. The noticeable flat spot before second. Jet came on has now gone and the van for a high top flies.

I’d have to have a proper search for where I wrote down stock vs current set up but will report back if I do.

E D I T: viewtopic.php?p=8231365#p8231365

No experience with other weber carbs fitted to the DG