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Weber 32/36 DGV squirting fuel into secondary barrel?
harmchar - 20/9/21 at 04:59 PM

Need some help from some of the carb experts. Got a Weber 32/36 progressive throttles. Been having problems with running rich and lumpy at idle and revving. Haven't had it on the road yet as just getting ready for IVA. While moving the throttle cable I noticed it squirting fuel into both barrels (primary and secondary) so fuel must be sitting in the secondary barrel and dumping built up fuel when the secondary throttle plates open.
Don't think it should be squirting fuel like that, can someone confirm that theory. Cheers.
I have also posted this on FB Pinto users group in case someone sees both.

David Jenkins - 20/9/21 at 05:05 PM

Some DGV carbs have an accelerator pump that squirts extra fuel in if the throttle is pushed quickly. This, as the name suggests, is to give it a boost when accelerating.

Try opening the throttle slowly - you shouldn't see the extra fual spray.

[Edited on 20/9/21 by David Jenkins]

harmchar - 20/9/21 at 06:30 PM

I think that's where my problem is. If I just so much as touch the accelerator lever with finger tip (engine off) it is spraying fuel into both barrels. Looking at some diagrams on different sites suggests there is a ball (like non return) that should stop leakage until throttle pedal is mashed. Think if my carb has this ball, it may be stuck open. Can't remember seeing a screw there that holds a ball in. Just going back to remove top cover of carb again.

nick205 - 21/9/21 at 08:04 AM

I used a Weber 32/36 DGV carb on my 2.0 Pinto engined MK Indy. I got the carb used and apart from having it re-jetted when the engine was setup on a rolling road the first thing I did was strip the carb fully and clean every part of it. The reassemble with a Weber rebuild kit of new gaskets etc.

It may be worth stripping it down and fully cleaning everything to make sure all parts of it are functioning as they're meant to. It's not a difficult job, just take some time and I recommend doing it somewhere you can lay the bits out as you remove them. Photograph everything as well so you have a reference when it comes to reassembly.

Mr Whippy - 21/9/21 at 08:35 AM

tbh I only remember both jets squirting at the same time and no ball but it was a while back... I do remember averaging 15 mpg with it on my 2ltr Pinto lol so pathetic

There is this rebuild vid - youtube link

nick205 - 21/9/21 at 10:35 AM

quote:
Originally posted by Mr Whippy
tbh I only remember both jets squirting at the same time and no ball but it was a while back... I do remember averaging 15 mpg with it on my 2ltr Pinto lol so pathetic

There is this rebuild vid - youtube link



I don't expect I was getting much different MPG with a 2.0 Pinto on a Weber 32/36 DGV in my MK Indy, but then I didn't build and wasn't driving the car for MPG. My daily diesel tin top returned the MPG for me.

Mr Whippy - 21/9/21 at 01:11 PM

True but it does limit range quite a bit for trips, especially with such small fuel tanks. That was with my JBA Falcon and I managed to run out of fuel on more than one occasion!

nick205 - 21/9/21 at 02:24 PM

quote:
Originally posted by Mr Whippy
True but it does limit range quite a bit for trips, especially with such small fuel tanks. That was with my JBA Falcon and I managed to run out of fuel on more than one occasion!



Sure it did limit the per tank range, but a fuel gauge told me how much I had and when to fill up. That said I didn't do any particularly long trips in the MK Indy, probably 35-40 distances at most.

crimondbanger - 21/9/21 at 10:40 PM

The accelerator pump can have either a double "carburetor pump jet" or single pump jet , both look the same but one has a hole blocked. Most folk use a double hole on the 2ltr pinto which sounds like the one you have.

There are 2 one way valves for the accelerator pump , one is buried in the carb and is pretty much impossible to get at , the other is the "pump delivery valve" its between the 2 air correctors and holds in the "carburetor pump jet". You should take this out and the little ball bearing inside should rattle and only let you blow through it and not suck when its vertical.

Having said that the accelerator pump should not effect idle or make it run rich at idle . Check your butterflys are closing fully on the secondary , and your idle mixture screw is set to 1 1/2 to 2 turns out.

New carb is 200 quid and can be bought properly jetted , money well spent , ive rebuilt lots of 32/36 webers and most used ones are well n truly knackered .

Hope that helps , i can take a pic of the bits if you need

James - 22/9/21 at 10:54 AM

quote:
Originally posted by crimondbanger

New carb is 200 quid and can be bought properly jetted , money well spent , ive rebuilt lots of 32/36 webers and most used ones are well n truly knackered .

Hope that helps , i can take a pic of the bits if you need




^^^^ This!

I bought a 2nd hand 32/36 for my 2.0 that was claimed to have been rebuilt.

I had to fill up every 2 days driving it back to work and back.... and it was a 7mile commute! So an MK-sized fuel tank every 28miles! lol

I was also having to 'double-blip' the throttle at every junction or it would stall or bog-down horribly as I pulled out.

Anyway, I bought a brand new carb from Southern Carburettors for about £225 and it completely transformed the car! Must've paid for itself in fuel saving alone in a few weeks.

harmchar - 22/9/21 at 04:45 PM

I was out at car last night and blocked off the accelerator nozzle that was squirting into secondary barrel. Seems to be better, not running as rich, but still couldn't get it to idle worth a damn. Will go out tonight and remove the carb again and strip out all the idle circuit and double check the throttle flaps are closing fully. I remember seeing a video saying the throttle plates have to fully cover. The two holes 1/8" up from plates or vacuum pulls extra fuel through.
Some good suggestions above. Cheers.
Really tempted to junk this carb and stick on a set of bike carbs but have heard they are a nightmare to setup good enough to pass IVA.

[Edited on 22/9/21 by harmchar]

Mr Whippy - 23/9/21 at 12:59 AM

One of the problems I've had in the past was the seals for the throttle plate shafts being worn and letting air get past which was making the idle all over the place. They were quite easy to change out, although the screws for the butterfly's are really tight (kinda what you want!).

If you give up on the carb as others have said I would just buy a new one as it will be a very worth well investment in the car and will last the lifetime of it. I would not go the bike carb route as tbh all that will happen is it will use even more fuel, be a pain to start and be more difficult to tune for the IVA test.

Have you absolutely checked that there are no air leaks into the manifold, hose connections, leaks etc., some pipe not covered?