Removing an engine from an aircooled Volkswagen

May 05, 2023

Dave House

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Before owning my first aircooled VW 5 years ago I had barely changed a spark plug. In the last 12 months I have removed my engine by myself twice! If you need to do some work on your Beetle or Bus engine this should hopefully give you the confidence to give it a go.

You don't need much to remove one of these engines but some things are better than others.

Get yourself in a safe position. If you‘re on the roadside and have another vehicle consider parking it behind you to reserve enough space. If you’re in a garage consider moving the vehicle forwards.

This guide is mainly for removing an engine on a bus, the general process is generally the same for a beetle but as you’ll be jacking the beetle up you won't need to remove the bumper or rear valance.

The rear valance or apron on a bus will slide off with the removal of 4 (or 2) long bolts that will be facing you when you open the engine bay.

You should find 4 bolts attaching the bumper bracket (2 a side) to the chassis. The bumper brackets have holes that allow you to adjust the bumper position so it's best to mark where the current nut is so you can put it back in the same place. You’ll need two spanners for this job as you’ll need to hold the bolt in place as you turn the nut.

Something will need to take the strain of the bumper as it's removed, this can either be your knees as you lie on your back undoing the bolts or some type of crate or dolly. Either way you do not want the brackets to bend as you unbolt the bumper or the bumper to drop onto a concrete floor.

Disconnect the negative terminal and lay it to one side, then do the same with the positive. When you come to reattach, positive terminal first, negative second.

Before removing any cables make a record of where things are now. Either take a few photos or mark each cable with masking tape, there's only a few things you need to remove but it's worth the effort, especially if it's your first time.

You should end up disconnecting:

Be careful when disconnecting any wires from the alternator or generator, if the wire has a "ring" connector between two nuts make sure to use 2 spanners, one to hold the bottom nut and one to loosen the top. Undoing the nut with one spanner can cause the terminal to spin and will often break the internal connection. I’ve learnt the hard way and broke my first bus’ generator doing this.

Once these are removed this part of the loom should be disconnected and it can be pulled through and laid to one side. You do not need to disconnect any wires that do not attach to the main loom.

This is going to vary slightly based on your set up but the fundamentals are the same. You’re going to need to clamp your rubber fuel line pretty close to the fuel pump, being careful not to clamp the fuel pump connector. I suggest getting some genuine clamps but if you’re stuck some vice grips will do.

Once clamped unscrew the clip holding the fuel line to the fuel pump barbed connector. Once that is loose gently pull the fuel line as close to the pump as possible. Sometimes you need to give the hose a helping hand and prise it off a little with a flathead screwdriver. Just be careful not to damage the pump.

Once it's off put it directly into a small jam jar or simply pull it through and point it at the floor. It will have a small amount of fuel left in it from the part of the hose that wasn't clamped. Once its stopped dripping put it on the left hand side of the engine bay so it won't get snagged as you pull the engine through.

You do not need to disconnect the fuel line that goes from the pump to the carburettor. If you’re planning to change it, do this after the engine in out.

The accelerator cable runs under the vehicle and gets fed through the middle of the fan housing and attaches to the carburattor. Different carbs have different fittings but you should see some type of barrel where the cable meets the carb.

Before you unscrew the cable barrel, put a mark on the cable just before the barrel with a marker. This way you can be sure to set the same tension again once you put the engine back in.

Once it's undone pull the cable back through the fan housing and lay it to one side.

One thing I missed out from the original post was detaching the cables that open and close the flaps on the heat exchangers to let hot air into the cab. If not detached your engine will hang up on these and you’ll probably break the connector. Your heat exchangers are the large pipe like things that connect to your exhaust at the back and run underneath the rocker covers. The heater cables sit at the top of the heat exchanger. You may find that your heater cables are already not connected or that you don't have any (perhaps you’re running J-tubes. If so you can skip this step.

This varies depending on model and particular set up but you’ll almost always want to remove the air filter from the top of the carburettor. This is mandatory on some models (e.g. with an original oil bath) but can be helpful even if you have a small pancake filter as they can get snagged on things and make the engine harder to put back in.

While this is not something that is actually required, the reason I do this is to help when putting the engine back in. At the back of the engine there is a flywheel with lots of little teeth that slot into the starter motor. It's not possible to put the engine back in when these teeth are not aligned so rather than having to wiggle the pulley while your engine is balanced on a jack stand I find it helps to set the pulley in a position that I know I can easily get back to to make re-entry that much easier.

Before you get under the vehicle grab a trolley jack and a piece of wood and jack it up just under the oil sump plate. At this point you just want to take the strain of the engine to support it, not actually raise it up.

The piece of wood will help you balance the engine when it's removed but also stop the jack damaging the sump plate.

If you have a motorcycle jack you’re in luck, because they can support the engine in two places it's not going to wobble!

If you have a dolly, you can put the jack through dolly at this point, as you won't be able to put it on later.

If you have a bay window bus you will have an engine support bar. I’ll be honest, despite having had 2 bay windows I’ve never had to remove the engines in them. I believe you remove the engine support mounts on either end of the support bar and you can keep the central part on as you remove the engine.

If the idea of crawling under an engine as you’re about to remove half of the bolts holding it up doesn't scare you a little bit I’d be surprised. This is why we take the strain of the engine with a jack and remove the bottom two bolts first.

First, find the bolts. Your engine has two studs on the bottom that feed through the transmission bell housing and get bolted up on the other side. It's easy to get confused with the bolts that hold on the transmission because they are more immediately visible. The ones you want are inset slightly which is why it can be better to use a spanner with an offset rather than a straight one.

I tend to lay on my back on the left hand side of the bus and reach over to the right hand bolt first. Once that's off I undo the left hand bolt on my side with my body not directly under the engine. These shouldn't actually be on too tight so normally come off with a basic spanner, at most you might need to extend your spanner for a bit of extra leverage.

Unlike the bottom, the engine does not have studs on the top just holes. This is because the bolts for the top go through the bell housing the other way and are bolted up from inside the engine bay.

There is some variation in what you might find on the left hand side top bolt but it will generally either be a captive (joined to the bell housing) or non captive (just a free bolt). If it's a free bolt you may need to also hold the bolt on the other side to undo it which may seem like an impossible task. However this can usually be achieved by either feeding a spanner through the rear tinwear or simply removing the rear tin so you can reach underneath. The ability to do this will vary on model but you will find a way!

The right hand side has a moon-shaped bolt that goes through the starter motor (outside the bellhousing) and then through to the engine. The moon-shaped bolt acts as a captive bolt, meaning it locks in to the starter allowing you to turn a nut without needing access to the other side while still being removable.

Undoing both of these bolts requires a fair amount of pateience and varying your body positon, often this is a task you need to do just feeling the bolts as it's hard to get your arms and head in position that works. This task is actually much easier on a beetle than a bus as you will have a lot more top down visibility (especially if you take the deck lid off).

Give the jack a little pump to take up any more strain if the engine moved after removing the bolts.

Now that you have all 4 engine bolts removed you are ready to pull the engine. However before you do this it's best to double check everything that attached the vehicle to the engine is disconnected and laid to one side.

A common problem is that people haven't pulled the accelerator cable out through the fan housing properly or it gets caught on the way out.

There are a few differences here based on the the vehicle type or the engine set up you have. For example, an engine with a single carb will drop straight down where as dual carbs will need a bit of extra wiggling or dropping at a slight angle. Make sure you have good clearance before you start the drop.

Pump the jack again and find somewhere on the engine where you can get a good grip, I tend to use the bottoms of the inlet manifold on either side.

Start to pull the engine forward with side to side movements. Before you can drop the engine down it needs to come forwards enough to completely clear the shaft that joins the gearbox to the engine. This is why it's important to do this in gradual steps and make sure the jack is there to support the weight once it detaches.

Once you feel the engine is free you can start to gradually let the jack down and pull the engine back towards you. Go slow and keep checking for anything that might be caught.

The process for putting the engine back in is exactly the reverse as taking it out. The biggest issue you’re going to have is keeping the engine stable when you try and line it up and push it back in. This is why I mentioned it can be beneficial to "Put your engine at Top Dead Centre (TDC)" before you take it out as it will hopefully remove one of issues.

It's much easier to put the engine back in if you have someone to help you out, debatably it's better to have someone to help you put it back in than take the engine out. Just keep taking breaks and check that your bottom engine studs are lined up and the engine is level before you make the final push.

If you’re second guessing your own ability, just take it slow and get another pair of hands to help you.