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CHAPTER 2

ENGINE DISASSEMBLY

It is human nature to be curious and wonder about the past a certain object has had. The old adage “if these walls could talk” is very fitting to the life of an engine and what it has endured over the years. With all the millions of Volkswagen engines still in service, the possibility of your engine having as many lives as a cat is not out of the question. Telltale signs of engines being rebuilt three, four, five, or more times may appear during the disassembly process.

Spotting a Rebuilt Engine

Most rebuilt engines are very obvious. The most obvious sign is a paint job. Volkswagen never painted its engines from the factory. Sure, the valve covers and other sheet metal was painted a semigloss black, but the engine case and cylinders were never painted. They had a coating that preserved them and prevented them from oxidizing for a period. The coating had a slight maple syrup color to it and didn’t last very long. Though a paint job doesn’t always constitute a rebuilt engine, a very good paint job is hard to achieve without cleaning all the grease and grime out of every nook and cranny and getting the paint to look nice.

Another sign that the engine has been rebuilt is random hand-stamped letters or numbers other than the factory serial number. These are usually stamped near the generator stand area. Don’t be discouraged if your engine has been rebuilt by a less-than-reputable rebuilder. As long as the majority of the components are intact, everything should be fine.

Be Patient

Don’t get frustrated during the disassembly process when fasteners may seem to be welded together. Remember, this piece of equipment might not have had a wrench put to it in more than half a century. Be patient and use the right tools.

Solvent-based rust penetrants, such as Liquid Wrench, WD-40, PB Blaster, etc., can help loosen things up. Apply them days in advance if you can, and don’t be stingy.

Apply heat if necessary to help loosen stuck fasteners. MAPP gas is a great, inexpensive source of intense heat. It works when a standard propane torch falls flat.

Tech Tip

Tearing down an engine “just for fun” is a good learning experience. Perhaps you came across a two-for-one deal while shopping for an engine to rebuild or someone is willing to give you a free engine to get it out of their way. Older 6-volt engines and partially disassembled engines are great candidates for an afternoon of fun and education. Whatever the case, it’s a great way to see what you are getting into before actually tearing down the engine you are going to rebuild. ■

If you are putting enough force on a fastener that you think it’s going to snap off, more than likely it will. There is nothing worse than a snapped off stud. Broken exhaust studs are super common and there is no reason for it to happen. An easy way to remove the nut is to sacrifice it. By that I mean to use the sharpest chisel you own and chisel the nut in half. Nuts are cheap, but broken studs are not.

The small 6-mm screws that hold on the sheet metal are commonly frozen as well. Hitting the top of the head of the screw to “shock” it loose works great. It’s worth a shot before pulling out the big guns (i.e., the torch). If hitting it doesn’t work, use an acetylene torch to heat the area around the screw. It will expand and break the fastener loose.

A Word About Safety

While you are swinging hammers and lighting things on fire, please use your head and be safe. Take your time and think about the what-ifs. Safety is not only the smart thing to do but also the most economical. A trip to the emergency room to get stitches or to get something removed from your eye can be very expensive and really throw a wrench in the budget and the timeline.

After you have an accident you always have the feeling of remorse. You instantly regret not being more careful or not taking the necessary precautions. So wear those safety glasses and put on those gloves. Get help if you need it and take a break if you need one. Nothing is more important than your well-being, and nothing slams the brakes on a project faster than a needless injury. ■

Get Organized

You’ve gathered all the tools and equipment necessary to start tearing down the engine. Before you begin, you will also want to gather items to keep your disassembly organized. The last thing you need is to start misplacing items from the very start.

Plastic bins are great for staying organized and hold up much better than cardboard boxes that just soak up oil and fall apart. The bins are available at most warehouse and home-improvement stores. Get enough bins to separate parts into three categories: parts to clean up, parts to take to the machine shop, and parts to replace. The parts you need to clean up can be put into a few bins. Most of these things will be put through the parts washer and inspected later. The parts you are going to replace can be recycled or sold outright. No need to clean them for this project.

Get out zippered bags and permanent markers. Put specific hardware in the bags and write on the bag in a language you can understand. Don’t get caught up in the correct terminology. The only person who has to understand what these things are and what they are used for is you. Putting smaller items to replace in metal bread tins or old-school coffee cans will keep everything in one place.

Don’t throw anything away until you are positive you no longer need it. Even a junk part that will only be used for reference is worth saving.

Taking pictures is a great way to reference parts and assemblies later in the process. You can take photos with your smart phone or a digital camera of things while they are still together the correct way, as you disassemble, and once they are in parts. Keep the photos organized for referencing later. When in doubt, take a picture. It’s easy and free.

Engine Disassembly

The main disassembly process will be exactly the same whether your engine is a 40-hp model from 1961 or a 1,600-cc fuel-injected model from 1979. The long-block will have nearly the same amount of parts and come apart in the same order. Let’s go step-by-step through the entire teardown process.

Disassembly

1. Remove the Gland Nut

Removing the flywheel can be a chore. It’s easiest to remove it before installing the yoke for the engine stand. The flywheel is held to the end of the crankshaft by one fastener called the gland nut, which is actually a big bolt torqued to 253 ft-lbs. Install the Helping Hand flywheel holder you made out of angle iron. Loosen the nut with a 1⁷⁄₁₆ (36-mm) socket and 3/4-inch drive breaker bar. A piece of pipe over the breaker bar will provide more leverage. Do not attempt to break the gland nut loose using a 1/2-inch drive socket and breaker bar. You will find the breaking point of these tools very quickly.

Shown here is the gland nut we just took off compared to a new one. You can tell someone had previously taken it off using the wrong tools (perhaps an adjustable wrench from the looks of the rounded off corners). This will need to be replaced with a new gland nut.

2. Remove the Flywheel

Use two long pry bars to wiggle the flywheel off the dowel pins. It shouldn’t take much effort. Be careful not to let the flywheel fall to the ground. Once the flywheel was removed, it was obvious why the gland nut was removed once before. The factory rear main seal (which was black) had been changed out for a new modern rear main seal (orange in color and made of a better silicone-based material).

3. Bolt the Yoke to the Case

Attach the engine stand yoke to the back of the engine case. Notice that it is attached to the left or 3-4 side of the engine only. This is so when the engine case is split apart, one half will stay connected to the stand while you remove the other half. The yoke will not fit straddling both halves.

4. Lift the Engine into the Stand

Slide the yoke into the stand. It weighs roughly 200 pounds, so don’t try to lift this alone. Get some help; better safe than sorry. Now is a good time to start draining the oil. Most sump plates will have a drain plug, but later models eliminated the plug, which forces you to loosen the sump plate at its six studs to get it draining.

5. Remove the Carburetor

Using a bent or curved 13-mm wrench makes removing the carburetor so much easier. Your carburetor may be full of fuel, so it is wise to empty it by turning it upside down and letting the fuel pour out the vent tube once removed. Note this is a stock Solex 34PICT carburetor and the vacuum lines have been plugged due to the vacuum advance distributor being replaced with a mechanical advance distributor.

6. Remove the Fan Shroud

Next to come off is the fan shroud and generator assembly. First, loosen the clamp holding the generator to the stand using a 13-mm wrench and a 13-mm socket. Slide it back toward the fan. Next, loosen the three bolts attaching the fan shroud to the tin work using a 10-mm wrench. There is one by each intake end casting and one by the oil cooler. Lift straight up off the oil cooler.

7. Remove the Intake Manifold

Loosen all four clamps that hold the sections of the intake manifold assembly together using a #2 Phillips screwdriver. Behind the fuel pump is a nut holding the center manifold to the case, remove it with a 13-mm socket. Next, remove the two nuts holding the end casting on the 3-4 side head with a 13-mm wrench. Pull the center section and 3-4 casting off as one piece. Finally, remove the casting on the 1-2 head using a 13-mm wrench.

8. Remove the Cooling Tin

This is what it should look like with all the cooling tin removed. All the sheet metal is attached with 6-mm flathead screws. Depending on how complete the engine you have is or what type of vehicle it was previously installed in will determine what sheet metal it has and what it will need when reassembling. Some of this hardware can be difficult to remove without sheering the heads off. Try to rap them with a ball-peen hammer to shock them loose and save you from having to drill them out and reestablish some threads in their place. Be careful using a locking pliers to loosen them. Penetrating oil and some patience would be a better route.

9. Remove the Crank Pulley

Here is a tried-and-true way of removing the crank pulley with minimal damage. Make sure the crank bolt was removed using a 30-mm socket and all the cylinder tin is removed, then tap the backside of the pulley closest to the center as possible with a large screwdriver and a hammer. It doesn’t take much force and it should walk right off. Crank pulley pullers tend to distort and permanently bend the thin metal pulley.

Even if this engine ran, it wouldn’t have lasted very long without severely overheating and self-destructing. The cooling fins are packed tight with oily crud, rat droppings, and other debris. Stored cars are magnets for furry animals to make homes and start a family.

10. Remove the Generator Stand

Remove the four nuts that hold the generator stand to the case with a 13-mm wrench. The baffle underneath the stand can be pulled off the studs. The one nut holding the distributor clamp to the case can come off as well.

11. Remove the Oil Cooler

Remove the three oil cooler nuts with a 13-mm wrench. There will be two nuts underneath by the 3-4 barrels and one up top toward the split in the case.

12. Remove the Sump Plate

By now, most of the oil has drained from the case and the entire engine can be flipped upside down. Remove the sump plate by removing the six nuts with a 10-mm socket. Pry off the sump plate with a screwdriver.

13. Remove the Oil Strainer

The oil strainer can be pried off the bottom of the case. It was intended to be serviceable by cleaning out and reinstalling it. This one is beyond that point and will be replaced.

Just look at that sludge! This engine was definitely neglected. Though obviously bad, it could be much worse. There are no signs of water damage; that thick, protective coating of goo preserved the sump area well.

14. Remove the Oil Pressure Relief Plungers

Special Tool

Use the special tool you made to remove the plugs. A couple quick blows directly on the head of the tool with a ball-peen hammer will shock them loose. The plungers should come out with a magnet.

If the plunger is stuck at the bottom of the bore, an easy way to remove them is to start threading a 1/2-20 tap into the backside of the plunger. It works every time without buying a special plunger pulling tool. This is the same tap we use to install case savers.

15. Remove the Valve Cover

Rotate the engine 90 degrees in the stand. With a large screwdriver, pry the valve cover bail down. Remove the bail by pulling the ends out of the holes on either side of the head. If the valve cover is stuck, wedge the blade of the screwdriver between the boss for the end of the bail and the edge of the valve cover and pry up.

16. Remove the Rocker Assembly

Remove the rocker assembly by removing the two nuts with a 13-mm ratchet. The spark plugs can come out at this time as well. Note that the rockers aren’t touching a couple of the valves, which is not a good sign.

17. Remove the Pushrods

Pull out all four pushrods. Put them directly in a large plastic cup to catch the oil draining out of them. Rotate the entire engine 180 degrees in the stand and repeat steps 15, 16, and 17 to remove the valve cover, rocker assembly, and four pushrods from the other side.

18. Remove the Head Nuts

The heads come off at this point. They are held on with special nuts and washers. Remove the eight nuts using a 15-mm socket and impact wrench if you have one. Start at the ends and work your way to the center when taking the nuts off.

Don’t be alarmed if the nut gets stuck to the stud and pulls the entire stud out of the engine case. Eventually, all the head studs will have to be pulled out and case savers will be installed.

19. Remove the Head

Once all the nuts are removed, it’s a matter of pulling the head straight up off the barrels. This may take some gentle persuasion with a dead blow hammer. Be careful not to hit any of the cooling fins on the head, which are cast aluminum and rather fragile.

Sometimes the barrels want to stay with the head while you pull them up over the studs and that’s fine. Just be careful not to drop a barrel on your foot. The pushrod tubes will either stick to the head or simply fall out. They will be replaced, so discard them.