Got my type 4 project car started but it wont idle

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retrovan
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Re: Got my type 4 project car started but it wont idle

Post by retrovan »

Thous look like 34-PDSIT 2/3 carbs

Maybe make sure on that fact so that the expert Dawie can give the correct info.

Last thing you need is to get the setup for the incorrect carbs.

some of these manuals also have the settings mixed up.

Herman


1952 Split Beetle 1835cc
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1972 Low Light Bay Panel Van 2Lt type 4
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mhsmuts
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Re: Got my type 4 project car started but it wont idle

Post by mhsmuts »

Agreed!

You learn through battling with issues. Cant wait to add value to someone else's project.
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Re: Got my type 4 project car started but it wont idle

Post by Dawie »

Its probably not idling because idle carb is not in circuit. And throttle stops on each carb probably set near closed, expecting the third carb to still be operational.

On top picture the green part shows flow of air through "idle/third carb" via metal "distribution pipe/balance tube as per "standard kombi application".
Air from air filter enters on top of "third carb". Outlet opposite cutoff valve connects via metal "distribution pipe/balance tube" to left and right inlet manifolds.

You could either set it up the kombi way with "third carb" in circuit.

Or the 411/412 way:
Ignore third carb, keep it out of circuit/ disconnected. Seeing that it was mainly an emission afterthought, these kombi carbs still have all the parts to run without this just like the 412 version of same carb. Just connect manifolds together with balance tube.
Count the turns the throttle stops are set from fully closed and write that down somewhere. (In case you want to go back to that setting).
Now adjust each throttle stop screw identical turns until you are happy with idle speed. Confirm size of idle jets stamped on side of jets, it may be something like "55". If there is an "off idle stumble" you may have to close the small bypass holes in the throttle valves.

At a later stage you could still add the hot air diverter thermostat system for better fuel economy and smoothness.
Staying Aircooled is so much nicer.
Do'nt assume anything- (While doing fault-finding).
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Re: Got my type 4 project car started but it wont idle

Post by mhsmuts »

Thanks Dawie.

I think Ill attempt the combi way first utilizing the third carb. Ill connect the two manifolds with a decent rubber hose and T it off to the port opposite the cut off valve?

The car only 'runs' if I manually rev it up to what I guess is around 2000 rpm, which to me suggests it is not just a matter of setting the stopper screw?

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Re: Got my type 4 project car started but it wont idle

Post by Dawie »

Especially when adjusting mixture on the "third carb" setup, remember that there is a delay after tuning screw. Mixture takes time to reach cylinder/ have an effect. So do slight adjustment, wait for the effect, do some more, wait, etc.
Like adjusting hot tap in the shower, effect happens slightly later.
Staying Aircooled is so much nicer.
Do'nt assume anything- (While doing fault-finding).
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mhsmuts
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Re: Got my type 4 project car started but it wont idle

Post by mhsmuts »

Adding the central idle system certainly was part of my idle solution, but there is more issues from what I can see.

It would idle and then just start taking strain to stay alive, rev it a few times and its better again. I suspect float level issues and air leaks at the gaskets?

I want to refurbish the carbs with a consumable kit, where would I buy this?



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Re: Got my type 4 project car started but it wont idle

Post by sean »

Double check for vacuum leaks before any other work on carbs.

If that’s all 100%, just loosen the idle jets half a turn out and see if there is an improvement. Blocked idle jets / circuit will cause this idle issues. If it improves, you have found the culprit. Strip and clean carbs and jets.

There are no carb kits available locally through the normal spares shop. Maybe try Volkspares. They only come with gaskets, o rings and needle & seat. No jets.

You can often get away with stripping and cleaning carbs without a kit. Clean everything properly, used compressed air to blow clean and re assemble.

For good cleaning results, use something with caustic soda like Zeb oven cleaner.
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Re: Got my type 4 project car started but it wont idle

Post by calooker »

I can supply rebuild kits. Rui 082 830 6493
For what it's worth, ignorance has no limits ......
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Re: Got my type 4 project car started but it wont idle

Post by mhsmuts »

Thanks to every body that helped. It now starts first time and idles like a new car.

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retrovan
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Re: Got my type 4 project car started but it wont idle

Post by retrovan »

Your two Vacuum advance ports are joined together with a "T" fitting and connected to the vacuum advance on the distributor.

The Idle air intake tube is best to be taken to the clean air side of your air filter. Yes it sucks in clean air.

Herman
1952 Split Beetle 1835cc
1968 Fastback 2Lt.type4
1972 Low Light Bay Panel Van 2Lt type 4
1975 Fleetline Panel Van 1914cc
2020 MeFusco Beetle Truck 2Lt type 4
1972 FT Hahn SP 1776 cc
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