Our webshop is full of technical information, with each part you get additional information about the applications, assembly instructions and so on. With this online publication we go a bit further, this will be your technical manual to work on your air-cooled Volkswagen. We discuss the technology of the VW Beetle, Karmann Ghia, VW Bus, the VW type 3 and type 4 and the VW Golf. You can read this magazine online, download it in PDF format and view it offline, or print it out.
adjust type 1 carburetor
The adjustment of the carburetor will determine the behavior of the engine. There are two types of carburetors for the type 1 engine when it comes to adjustment. The old generation (up to SOLEX 30 PICT-2) with two adjusting screws and the young generation with three adjusting screws (from SOLEX 30 PICT-3), recognizable by the large screw in the carburetor housing.
engine types and codes
The engine number indicates which type of engine is involved and with which engine capacity. The first letter(s) determine the capacity and type of engine and the following figures determine the year of manufacture. The engines up to and including July 31, 1965 had no letters for the engine number, which is why up to and including this year of manufacture only numbers are given.
basic electrical circuit diagram
An electrical problem is difficult to detect when you cannot distinguish the basic components. After a restoration, you will have to reconnect the electricity, step by step is the message. Let's try in this article to make the electrical circuit of our VW simple, all cars eventually use the same basic circuit diagram.
crankshaft types
The heart of the engine is the crankshaft. Literally, everything revolves around this piece, we can compare it to the human backbone. The robustness and optimal performance of this component is therefore essential for a reliable engine, especially when the engine has to push a heavier VW Bus or when the engine has more horsepower than standard.
mixture preheating
The engine is stopped as a result of poor combustion. This bad combustion is often caused by a, at that moment, wrong composition of the fuel in the cylinders. Because of this bad combustion, the engine does not deliver the desired power and you can feel this in the form of stuttering of the engine.
6 volts and 12 volts
Until the early 1970s, the VW Beetles were equipped with 6 volts in their 1200 cc version. The 1300 cc Beetle was first equipped with a 12 volt system in 1968. The VW Bus and type 3 VWs were increased to 12 volts in 1967. Types 4 are in 12 volts, as they were only introduced to the market in the late 1960s.
HPMX carburetors
The most famous double carburettors are the Weber IDF and the Dellorto DRLA. Since a few years there is a new player on the market, namely the HPMX carburettor. This is marketed by EMPI and is also sold as a complete set, including manifolds, air filters, linkage and mounting material.
radio interference
Have you ever driven a classic Volkswagen with an original radio or a classic radio, then you have probably ever known the phenomenon "interference". That annoying noise, buzzing, crackling that comes out of your speakers. These disturbances can have different causes, but they can also be remedied.
the valve clearance explained
The valves of the VW boxer engine ensure that the petrol air mixture can be fed into the cylinders (through the inlet valves), and that after compression this mixture can be discharged through the exhaust (exhaust valves). An accurate adjustment of the valves is of utmost importance for the proper functioning of your engine.
setting valve clearance
The first technical work I ever did on my first Volkswagen Beetle was to set the valves. I didn't know much about the technology of the VW Beetle at the time, but I dared to do it, valve setting is easy to do yourself, you don't need many tools, and it's essential for the proper functioning of your classic.
the clutch: basic concept
For a long time I wondered how the clutch in our Volkswagen Fastback worked, I was only six years old. I didn't understand very well that by releasing a pedal our VW started to drive spontaneously. Well, if you understand how disc brakes work, then the step to understanding how the clutch mechanism works is not far.
finding the top dead center
What does Top Dead Center (TDC) actually mean? If you study the theory of the operation of an internal combustion engine - or the "petrol engine" - it will become clear. Without going into too much detail about the theory, we have to talk about the otto cycle, better known as the four stroke cycle.
mesuring the compression
How can you determine very objectively how much wear the engine has? An indication of the wear level can be obtained by performing a compression measurement, the engine compression determines the power of your VW. Anyone can perform a compression measurement on an air-cooled or water-cooled VW.
oil leakage
(dis)assembly of the spark plugs
cylinder head specifications
One of the most heavily loaded parts in the air-cooled VW engine is undoubtedly the cylinder head. Especially the valves, valve guides and valve seats have to endure a lot because of the high temperatures, the temperature differences and the mechanical load in an air-cooled engine.
oil consumption
Oil leaks are easy to rectify, sometimes even without having to remove the motor. We have saved the more difficult cases for this article, so we did not call this "oil leaks part 2" but "oil consumption". The distinction between the two is sometimes difficult to make, hopefully the information that follows will bring clarity.
the VW suspension
Ferdinand Porsche came up with an ingenious concept at the beginning of the last century. A car that was built on the basis of a steel chassis plate with an independent and self-supporting body. Most of the cars from that period were built around a tubular chassis, so the Volkswagen Beetle (then still a Kdf-car) was revolutionary.
replace a thread
When you are working on your VW, you will encounter this problem at some point; a bolt of the crankcase cover doesn't really turn in the thread in the crankcase anymore. The more you try, the worse it gets. There is too little tension between the crankcase cover and crankcase, with oil leakage as a result.
replacing the clutch
The clutch is an important mechanical part of your classic Volkswagen. The complete system with clutch plate, pressure group, thrust bearing, flywheel, pilot shaft and clutch pedal must be in good condition and properly adjusted. In Paruzzi Magazine edition 06 we have explained the principle and parts of the clutch system.
the distributor
The intention is that we can adjust the ignition of our classic Volkswagen ourselves. First you have to know which parts have an influence on the operation of the ignition and you have to understand how the ignition circuit works, this is very important to be able to make a good diagnosis and to be able to adjust the ignition later on.
air filter preheating
It seems to be a natural part of your air-cooled engine, but the air filter plays a crucial role, it's like breathing in a human being. The carburettor is tasked with mixing petrol with air to deliver a flammable mixture. Petrol alone is not a good fuel. That requires oxygen and not just a little bit of it.
vacuum advance
Both the vacuum advance and the mechanical advance were used for the VW Beetle, Karmann Ghia, VW Bus, VW Thing, type 3 and type 4. You can't stick a year of manufacture or type of engine on it, both systems do the same thing in the end, they bring forward the ignition time depending on the engine speed.
air filter thermostat
The preheating of the fresh air supplied via the air filter to the carburettor is a part of our VW engine that gets too little attention. This system will ensure that in all weather conditions the carburettor is supplied with air at the right temperature. With these younger air filter models you don't have to adjust anything in contrast to the older models.
drum brakes
Almost all classic VWs are equipped with drum brakes at the rear and front, a number of models such as Type 3, Type 4, Beetle 1300S, 1302 and 1303 and Bay Window Bus were first fitted as an option and then standard with disc brakes at the front. Of course, you can convert any drum brake into a disc brake if you wish.
crankshaft seal replacement
If you find that the crankshaft clearance is outside the factory specifications, replacing the crankshaft seal will not be a solution for the oil leak you have identified. If the crankshaft clearance is less than 0.30 mm, it makes sense to replace the oil seal, otherwise a total engine overhaul is the only worthwhile option.
underneath the VW 1200
When I bought my first Volkswagen Beetle convertible, I had a lot of problems starting. On a hotel parking lot the starter motor failed, I had heard that you had to knock on the starter motor to release it, but I had no idea where it was. Is this a familiar situation for you? Then this article is exactly what you need.
underneath the VW 1303
We are going to study the "more modern" VW that in the early seventies had to compete with brands like Opel and Ford but also with the Japanese brands like Datsun and Toyota. VW introduced new technologies to revitalise the obsolete Beetle concept before the water-cooled VW Golf was ready for production.
fuel circuit - concept
The combustion engine of our air-cooled Volkswagen uses a mixture of petrol and air. It is extremely important that both the amount of air and the purity of the air are regulated, this also applies to the petrol. Unfortunately, the petrol circuit is not very well known to enthusiasts and it is not always well maintained.
ignition timing - dynamic
In this edition, we will adjust the ignition with the engine running, this is called a dynamic measurement. VW advises in its workshop manuals this way of adjusting all air-cooled VWs from August 1970 onwards. The static adjustment with a test bulb is then only suitable for a temporary engine adjustment on these young Volkswagens.
spark plug heat range
The construction of the part of the spark plug that is screwed into the cylinder head determines the degree of heat. The spark plugs are screwed into the cylinder head, which is the warmest spot of the engine. Temperatures can be as high as 1000°C. The electrode part of the spark plug extends into the combustion chamber of the cylinder head.
independent suspension
Fixed one-piece front axles with leaf springs or torsion springs as on the VW Beetle, were widely used until the end of the sixties. Due to the demand for more comfort, better steering and by driving longer distances, the independent front suspension became more and more popular on luxury cars.
removing the MacPherson
Sometimes it will be necessary to disassemble the MacPherson. It is located at the front on younger Volkswagen models such as the VW Beetles 1302 and 1303 and the VW Vanagon and at the front and rear on the VW Golf and VW 411/412. We will show how it works on a VW 1303, repair the bearings and install.
wheel play adjustment
The front and rear axles of your VW are mechanical parts that have to withstand a lot of forces. They are designed to withstand the full weight of the car, but they are also designed to absorb the forces that occur during acceleration and braking, which are several times greater than the weight of the car.
the condenser explained
The condenser is the most misunderstood part of the motor. What is inside that metal cylindrical part? So, what does this part actually do? Is it really necessary for the proper functioning of the engine? In this article we will limit ourselves to explaining what a capacitor is and what it does, and to measuring and testing the condenser.
installing the engine
In edition 16 we explained how to remove the engine of a VW Beetle, two techniques were discussed. The most important points of attention for the installation of the engine are indicated in this article. During the installation of the engine you will have to position the pilot shaft of the gearbox perfectly opposite the centre of the clutch.
axle play with dial gauge
The wheel play of the front wheel axles must be accurately adjusted. It can be done by feeling, but what if you don't have that experience. If you don't trust your gut feeling, or you are more of the type that wants to measure everything accurately, then adjusting the wheel play with a dial gauge is something you will appreciate.
using the dial gauge
A dial indicator is part of the basic equipment of the professional mechanic. As an enthusiast of automotive technology, you will soon need such a precision measuring tool. For example, to measure the axial crankshaft play, to measure the straightness of the disc brakes, the front wheel play, or during the overhaul of the engine. We explain how to use a dial indicator.
measuring the coil
Everyone knows that the capacitor will protect the contact points from burn-in. But what few people know is that the capacitor also plays a very important role in transforming the low voltage of the battery (6V or 12V) into a high voltage (more than 10,000V) needed to create a spark between the electrodes of the spark plug.
type 1 sump plate
bearings replacement
front wheel bearing replacement
If the wheel bearings are worn or damaged, there is no point in adjusting the wheel play. You will first have to replace the wheel bearings to get a good result. In edition 18 we tuned the wheel play of the front wheels to the feel, in edition 19 we fine-tuned the wheel play by using a measuring clock. In edition 21, we are replacing the front wheel bearings.
sump plate stud length
How many VW enthusiasts are surprised that the engine leaks after an oil change? Read all about the type 1 sump plate in edition 20, what to look out for, how to attach it and with which tools. In this edition we will determine the maximum length of the sump plate studs, to prevent oil leaks.
replacing the sump plate studs
If the studs are not tightened properly, it is practically impossible to tighten the crankcase sump plate to compress the paper gaskets. The infamous engine oil leak is the result, and no, it is not normal for an air-cooled VW to leak! A leaking engine will be rejected at the mandatory technical inspection.
replacing spade connectors
A messy electrical connection will soon lead to the failure of electrical accessories or, in the worst case, the engine. Incorrect connections can also result in short-circuits, causing the wiring harness to burn out. Enough reasons to master a good technique to make the electrical connections of your VW neat and tidy.
replacing brake drums
voltage drops
The electric consumers of your classic Volkswagen expect the full 6 volts or 12 volts (or more) to function properly, which is unfortunately not always the case. Especially the 6 volt version sometimes complains about slow running windscreen wipers, weak headlights and direction indicators that pinch too slowly.
swing axle and IRS
installing rear brakes
In issue 23, we removed the rear brakes from our VW 1303. All classic Volkswagens were equipped with drum brakes in the rear, the procedure for other models is quite similar. If you used the previous edition to replace the rear brakes on your VW, you should be able to continue your work with this article.
determine cable diameter
The older your Volkswagen the more likely it is that the electrical consumers no longer get the full 6 volts or 12 volts due to voltage losses between the battery and the consumer. A voltage drop across the electrical conductor is inevitable, we are dealing with copper and we cannot make the cross section of the cable infinitely large.
metric bolts
crankshaft pulley removal
Caster and Toe
In the previous edition, we explained what Camber and King Pin Inclination (KPI) are. An important consequence of KPI is the Scrub Radius, which is the friction radius of the front wheels. In addition to Camber and KPI, there are other important parameters, such as Caster angle and Toe.
brake circuit bleeding
Of course, flushing the brake fluid is not always necessary. If you have disconnected a brake hose or line, or you have disassembled a brake cylinder or caliper, then bleeding part of the brake circuit is sufficient. This saves brake fluid and it's done faster than complete flushing.
dynamo operating principal
Wouldn`t it be nice to know what DF means, for example? And what does D+ mean? If you know what`s behind these letters and numbers, then connecting the dynamo will be a breeze. In this article, we will explain the working principle of the dynamo, also known as a direct current generator.
alternator operating principle
The direct current dynamo greatest asset turned out to be its greatest limitation, the collector. Supplying more current would shorten the life of the carbon brushes; something had to be found for that. So the dynamo no longer sufficed for the new situation of the mid-sixties.
measuring electric current
To measure current, you must interrupt the circuit through which the current flows. The ammeter must be connected in series. Therefore, that a current clamp is a better solution. This type of ammeter does not affect the circuit to be measured, it measures the magnetic field around the conductor (induction principle, see edition 26).
measuring front wheel geometry
In this edition, we will explain how to measure front axle wheel geometry, and what the values are for each type of classic VW. Camber Angle, Toe and Caster are discussed in this edition. Measuring the rear axle is covered in edition 28, and in edition 29 we will show how to adjust front and rear axle wheel geometry.