Missing pipe from air filter to scoop?

[Sagemagoo]

Evening all,

Is there supposed to be a pipe connecting the air scoop at the back of the van down to the air filter? At the moment I've got a short piece of pipe from the airbox leading to an elbow pointing up towards the scoop then...nothing.

Cheers

[Mickyfin]

What engine? Photo would help too.

[ghost123uk]

Aye, can you explain (or provide a pic) as to what you are referring to when you say "air scoop"

[kevtherev]

Evening all,

Is there supposed to be a pipe connecting the air scoop at the back of the van down to the air filter? At the moment I've got a short piece of pipe from the airbox leading to an elbow pointing up towards the scoop then...nothing.

Cheers

if it's a petrol the whole assembly looks like this..



and this fine example is for sale!

[Ian Hulley]

What engine? Photo would help too.

AAZ Homebrew

[Woody49]

Maybe this will help , but I don't think it shows the bit you are talking about.
I am missing the two hoses 13 and the tee'd elbow 6 and the other vertical bit you have so please PM me with details of for sale.

I have a DG petrol 1989 with heat exchanger on the exhaust for items 13 but have no idea of what is stock. So interested in what the experts say.

Regards

[philby71]

i have a 1.7 diesel and is not connected, should diesels have the upright pipe section as well ?

[kevtherev]

ooop I missed it too

[colinthefox]

There should be a corrugated pipe with a fibrous lining from the elbow to the air scoop. It is also a sound attenuator, so will reduce engine intake noise. Unfortunately they tend to disintegrate internally, and get thrown away as a result. Even when in good condition,they are also a restriction on airflow to the larger engine.

So without it, the air pressure and airflow developed by the specially designed air scoop will be wasted, and won't get to the engine. The engine will be a whole lot noisier than it needs to be. The intake noise can be as loud as all the rest of the engine, and is why the engine sounds like it will burst at 50mph.

You can make a replacement from a length of PVC rainwater downpipe shaped with a hot air gun. Fiddly yes, but well worth the effort.

[karmannkarmann]

Evening all,

Is there supposed to be a pipe connecting the air scoop at the back of the van down to the air filter? At the moment I've got a short piece of pipe from the airbox leading to an elbow pointing up towards the scoop then...nothing.

Cheers

if it's a petrol the whole assembly looks like this..



and this fine example is for sale!

Mine is also
Missing the silver corrigated pipe, I have the elbow but no pipe, where does the bottom end connect too?

[Sagemagoo]

There should be a corrugated pipe with a fibrous lining from the elbow to the air scoop. It is also a sound attenuator, so will reduce engine intake noise. Unfortunately they tend to disintegrate internally, and get thrown away as a result. Even when in good condition,they are also a restriction on airflow to the larger engine.

So without it, the air pressure and airflow developed by the specially designed air scoop will be wasted, and won't get to the engine. The engine will be a whole lot noisier than it needs to be. The intake noise can be as loud as all the rest of the engine, and is why the engine sounds like it will burst at 50mph.

You can make a replacement from a length of PVC rainwater downpipe shaped with a hot air gun. Fiddly yes, but well worth the effort.

Thanks - this makes sense. How does it fit onto the air scoop ?

[Woody49]

For Karrman's benefit - the two hoses fit onto two outlets on a ' heat exchanger' attached to the offside rear exhaust pipe (just near the gearbox).

IMO - This seems to be a carryover of practise from Bay Window days. To aid start up item 2 in the diagram above, which is a temperature sensor allows the vacuum to draw and open the flap in the control box (item 2) when the engine is cold. When the air box gets hot the sensor switches off the vacuum and the flap closes increasing the amount of cold air going into the system.

It seems a matter of measuring sizes and lengths and maybe using other vw or commercial hoses.

I bet the sensor is the weak point. My van has most of these bits disconnected (by previous owners), hence probably the reason why its a bit lumpy when cold.

Someone please correct me if I am wrong or better still confirm if I am right.

[Ian Hulley]

Even in -28 2 years ago the missing air pre-heater made zero difference to my van running, perhaps in the arctic circle yes ... in the UK ? nah.