Volkswagen Camper & Commercial – May 2019

26 BUS DOCTORwww.volkswagencamper.co.uk

Steve Leatham answers some of your questions...

Email [email protected] Address Bus Doctor, VW Camper & Commercial, The Old School Higher Kinnerton Chester CH4 9AJ

http://www.GermanCamperCompany.com

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Bay Bias Valve

Dear Bus Doctor,

Having not driven my bus for

about 3 years, getting used to the

vagueness of an old air-cooled is

quite something owning a T4 and

a new Golf. One thing which has

bugged me for a long while is the

performance of the brake system.

When rebuilding my bus just over

a decade ago I looked at the system

and realised there is a bias valve at

the front that essentially works on

the angle of the bus. Here lies the

problem!

My bus is lowered about 6” at the

front, at the back it’s lowered about

1 spline, but has big 205/70/16 rear

tyres, so the it’s got a fair bit of rake!

My concern with this is that the

rear brakes never work as hard as

the fronts because of the bias valve

thinking the bus empty, even when

loaded. During MOTs it’s ok because

the bus will sit level with the rear

wheels in the rollers, meaning the

brakes perform much better.

I’ve no idea if the thing is working

as it’s a sealed unit and has no

external moving parts to check (it’s

supposed to have moving internals

and springs etc)

I’ve had a quick google, but didn’t

really find much useful, so my

question is, could I just eliminate the

bias valve on the camper entirely?

I presume then it would brake

like it’s fully loaded, it’s always got

a camping interior so that’s a load

extra weight it always carries.

Tim Alden

A trick that is often used is to

elongate one of the mounting holes

so that the regulator angle can be

“fine-tuned” and thus alter the

amount of bias. If that doesn’t make

any difference, I wouldn’t have any

qualms about bypassing it. Note that

Bus Doctor

there were 2 completely different

regulators used, early design for

‘71/72 and later design for mid-73 up.

Which Brake Callipers?

Dear BD

I have a pair of T2 front brake

callipers but I can’t remember what

vehicle they are from!

It would be either a ‘71 bay with low

front indicators and small tail lights,

or alternatively a ‘71 bay “crossover”

with low front indicators and large

rear lamps.

I understand there are early and

late versions of calliper and I don’t

know when the change occurred.

Can you tell me how to tell one

calliper from another?

Lammy 

Yes, there were 2 types of calliper

used on ‘71 models. The early one had

only one bleeder, beginning in Mar

‘71 a second bleeder was introduced

(upper and lower). This later type

was used until the monster calliper

was brought in for ‘73 models.

Broken Fuel Gauge

Dear Bus Doctor,

The fuel gauge hasn’t worked since

getting my bus, a garage diagnosed

and fitted a new sender. All was

good but a few months later it’s

stopped working again.

I’ve removed the sender and it

seems to be functioning OK, when I

reconnect the wires one way there’s

nothing at the gauge, swap them

over and the needle goes off the

scale.

I thought it was an earth issue

but I’ve run a fresh earth and have

grounded each terminal with

the wires each way round but

it’s still the same. Any help much

appreciated.

Mark Ripley

The gauge sort of earths through

the sender. Swapping the wires

directly earths the gauge without the

resistance of the sender, causing it to

read full. Don’t do this for longer than

a second or two, you risk burning out

the gauge but you’ve proved it works.

You have voltage at the sender, how

many volts? - should be 4.8v IIRC.

So it must be the sender? Disconnect

its wires and measure the resistance

across the terminals. Expect 8-120

ohms. If it’s open circuit it’s broken.

Engaging Gear

Dear Bus Doctor.

Since getting my Split, second gear

has been difficult to engage and

impossible from cold. I’ve removed,

re-bushed and re-greased the

linkage, fitted a short shift kit and

tried multiple adjustments of the

plate including putting into second

then tightening the plate but I can’t

get it any better.

All the other gears engage fine,

second is OK when warmed up

but from cold it’s a no no and I

have to skip to third. Am I missing

something?

Rick

If it goes into gear better with the

engine off, try adjusting your clutch

cable 2-3 turns tighter.

The lockout plate - well, I hear over

and again of people adjusting it hoping

to get 2nd more easily but it’s got to

be way out to be the cause. It feels like

there’s a wall between neutral and 2nd

and occasionally drops straight in.

The problem is the (primary??) shaft

in the box spinning when

it shouldn’t be i.e. the

clutch dragging or

the pilot bearing

is damaged and

causing the shaft

to spin.

Steve Leatham

has been working

on and restoring

VW buses since

1997, tackling just

about every job

over the years. He

has been resident

Bus Doctor for the

mag since 2003.

Got a problem or a query?