Flatspot.

[ghost123uk]

After sorting your tank / filler problems I would then check the primary main jet for crud, that can cause a flat spot on accelerating, just before the secondary barrel comes in (had it on our Scirocco 2 weeks ago, same carb) Whilst there look in the float chamber for any more bits, it always amazes me how, even with a good fuel filter, crud gets in there !

p.s. Take care when splitting the carb (dead easy) of the gasket as if you damage it you will need a new one (about £1.50) - Note = never use any type of sealer on carb gaskets.

[Dave307]

Thanks it's gonna be a nice little job for the weekend.
Was gonna go camping but think it needs sorting first.

[Dave307]

Ok. So just dropped the baby off at my mechanic to get the flat spot backfiring etc sorted. He takes one look at the fuel filter (inline) and says it looks like you have water in there. Doh I say.

So I have left it with him to to drop and sort fuel tank. Clean the lines and the carb. Fingers crossed that will sort it.

Any idea how expensive that will be. Can't see it being to bad myself.
Also how does water get in a sealed fuel tank.

[ghost123uk]

Also how does water get in a sealed fuel tank.

Sadly usually through a rusty great hole in the top of the tank, a "feature" of these vans

[Dave307]

Well been a good day.

Got the van back from my mechanic.

He has stripped and cleaned carb. Apparently the jets were full of sh*t. Dropped and drained and cleaned the fuel tank. New huge in line fuel filter.

Apparently there is a little plastic thing in the choke that is worn and he has advised to look for a new carb to replace the existing one sooner rather than later.

Van now runs like a dream. It's running a little fast but he said that due to the little plastic bit being worn it will. Nothing major about 1100 rpm rather than 900 rpm.
He also said that it could do with new dizzy, rotor arm, sparks and leads at some point.

Other than that it is running great again. Apparently the water got in due to me pressure washing around the back of the fuel filler cap which is only plastic or something.

Anyway I'm happy and will start sourcing carb soon.
If anyone knows the best place to get one please let me know.

[kevtherev]

seems a little drastic to replace the carb ...for a piece of plastic
I have a used carb that you could break for the part

what exactly is broken, can you find out?

[toomanytoys]

He prob means the choke pulldown unit... quite easily sorted...
Dizzy.. he doesnt mean the whole dizzy.. he prob means just the cap..

You should check your fuel filler neck and rubbers.. the early steel ones rust and road crap and water get in.. the rubbers perish and let water and crap in.. if you dont fix this, it will be running like crap again in another 200 miles..

[Dave307]

Right I am no expert and my knowledge is limited. But I'll try to explain as he did.

It's a pierburg 2E3 carb. Now apparently it has a second choke that operates as the engine gets warm and the little plastic bit is the part that opens and closes that valve apparently it's worn is therefore not closing or opening the valve properly.
I may be wrong in my explanation but I think that's right. He did say it could be stripped and replaced if the part could be sourced.

[toomanytoys]

The second choke is opened by vacuum.. (as similar unit to the pull down unit) if this isnt working, the performance is reduced..

[Dave307]

He prob means the choke pulldown unit... quite easily sorted...
Dizzy.. he doesnt mean the whole dizzy.. he prob means just the cap..what exactly is broken, can you find out?

The choke pull Down unit sounds like the thing

You should check your fuel filler neck and rubbers.. the early steel ones rust and road crap and water get in.. the rubbers perish and let water and crap in.. if you dont fix this, it will be running like crap again in another 200 miles..[/quote]

.
He checked all the neck for me and said it all looks fine. He suggested I don't pressure wash under it again as I did before as that can force water in to even the fittest seals.

seems a little drastic to replace the carb ...for a piece of plastic
I have a used carb that you could break for the part

[Dave307]

Oops messages and quotes got jumbled up the sorry.

[kevtherev]

Yes it is the choke pull down unit as Simon suggests.
Available from Brickwerks easily fitted.
the pull down opens the choke flap when the engine is cold or the engine would over fuel and stall.
It's in use for the first five mins of running then it's redundant.
It is not responsible for idle speed. that is governed by the idle speed screw and when cold the fast idle cam.

[Dave307]

Yes it is the choke pull down unit as Simon suggests.
Available from Brickwerks easily fitted.
the pull down opens the choke flap when the engine is cold or the engine would over fuel and stall.
It's in use for the first five mins of running then it's redundant.
It is not responsible for idle speed. that is governed by the idle speed screw and when cold the fast idle cam.

Ah cool I'll check with him that's what he means and then get on to brickwerks.
That will be cheaper than a new carb

You peeps are great I just keep learning.
Thanks.

[toomanytoys]

Oops messages and quotes got jumbled up the sorry.

No problem....

BUT.. if you have water and dirt in the fuel filter and carb, then its getting in, ther is a problem somewhere..... could be the top of the tank is perforated or the breather pipes (to expasion tanks, some are hidden on top of the tank too) are perished and leaking.. they are a pain to do in place, but possible...

[ghost123uk]

It's a pierburg 2E3 carb. Now apparently it has a second choke that operates as the engine gets warm and the little plastic bit is the part that opens and closes that valve

Dave, as I (we) know you are learning, I hope you don't mind a little "lesson" (and I hope I ain't "teaching grandma to suck eggs")

Re "Chokes" on carbs.

In the UK we have the habit of referring to 2 very different parts of a carb as "chokes".
The "choke" as most drivers know it is (as mentioned above) a clearly visible flap at the top of the carbs primary air intake that, when the engine is cold, blocks a lot of the air from getting into the carb to make it run better (richer) when cold. These used to be operated manually by the "choke lever" on the dashboard, but are now automatic and operated by heat in the water system.

Now the complication / confusion =

If you look down at the top of the carb (air filter assembly off of course) you will see that there are 2 air inlets (one has the above mentioned choke flap at the top of it). Now in the USA (etc) these 2 air inlets are called "barrels" but here in the UK they too are called "chokes" So when a mechanic says there is a problem with a choke, he could mean the choke that is for cold starting (that "flap") or it could mean a problem with one of those 2 visible big air intake "barrels".

Now when he says = "apparently it has a second choke that operates as the engine gets warm and the little plastic bit is the part that opens and closes that valve" there is some ambiguity. The "second choke" refered to is nothing to do with the engine warming up. It is a second "barrel" and it starts to provide the engine with extra fuel and air at (roughly) above half way down on the accelerator pedal. It is operated by a thing called a "pull down unit" (a vacuum operated diaphragm and lever) when the engine is under load (i.e. pulling hard) as Simon and Kev mention above.

~~~~~~~~~~~~~~~~~~~

For once I have no problem with an Americanisation and think we should call them "twin barrel carbs" not "twin choke carbs". I know mechanics know what it means but it can be confusing.

Oh, and I agree with what has been said above about water ingress, the mechanic is "miss-guided" when he says it got forced in past a seal by a pressure washer. It is much more likely a hole somewhere

Hope all that is of some value