This might go down as the most stressful thing I've ever done. Finals week ended at the end of April, and my internship just started on the first of June. School kept me too busy to work on engine, especially because I didn't have a car to ride up and down from Atlanta back home where my car was. So, when school let out for the summer, I had about four weeks to go from bins of engine parts to engine, in car, 650 miles north in Baltimore, and... spoiler alert, I didn't make it.
I guess I don't have any posts about why I'm having to do this in the first place. The short story is, I was in rural Virginia volunteering for a week, and one morning driving down the highway (at a fairly good clip for my little Beetle) I lost all power, I was slowing down with the pedal to the floor, which is usually not a good sign. I pulled over, and naively attempted to restart the engine, it started but was running really rough. I had no clue what was wrong, so checked the distributor (I'd had issues with low-budget caps wearing out) and it looked passable. For whatever reason I decided to pop off the rocker arm covers, and to my surprise, under the 3-4 rocker cover I uncovered a disaster. The nuts holding the rocker arm assembly to the head had backed themselves loose, allowing the pushrods to hop outside the cups in the rockers that they're normally captivated in.
I got the car towed to a garage nearby that I had access to and tried to piece it back together. The only thing I really feared was the pushrods being bent, so I rolled them on a flat surface and checked to see if they stuck anywhere. They appeared fine so I kind of put everything back together, did an oil change, and adjusted the points and timing. Standard tune up. I needed to be back in Atlanta to visit the French consulate, so I took the risk and drove it back to Atlanta. Got about an hour into the trip until things started sounding strange around Asheville. Pulled off the road and my head temps (measured with a laser temperature gun) were about 100°F too high, and the engine was running incredibly rough. I called it quits and my dad (who happened to be on a business trip nearby) had to rescue me. I came back a day or two later and picked up the car from the gas station I had to leave it at.
When I got it back to Atlanta, I did a compression check and discovered the engine had very low compression and I also found a nice clump of metal shavings in the oil strainer. So, rebuild it was. I got the engine out of the car before I left to France for a Fall semester abroad, and my car sat without an engine for the Fall and Spring semester.
The first step (which started before school was out) was to pick parts. I browsed and browsed forums and asked countless questions and read numerous articles and really just came up hands empty. People are incredibly opinionated when it comes to part selection for stuff like this, and it's especially difficult because there's really no scientific way to say that your parts combination came out better than somebody else's parts combination, especially when it comes to long term reliability. What helped me the most was Clyde, a local parts seller and friend in Athens, Georgia who supplies a lot of parts to the Volkswagen group I hang out with every once and a while. What I found is that, you really just need one very opinionated person, who only gives you one option, and who has built many engines in the past. It's impossible to get good parts advice from somebody who has only built one engine, they're going to be convinced that their choices were the best choices.
Clyde helped me select the parts, which of he stocked of course, and I purchased almost all of the parts I needed from him. I trusted him, especially because there were times when I asked him if I needed a replacement for something and he told me to stick with what I had. He wasn't trying to maximize his profit from me.
This was huge time saver. When I disassembled the engine, I made sure I put every bolt, washer, nut, screw, and assembly inside a labeled bag. The first thing I did was organize all of these parts on a table along with the new parts, which made it really simple to do inventory.
After talking with Clyde at length, I decided to upgrade the heads, pistons + cylinders, and cam. I had Clyde install some heavier duty springs in the heads (which should allow for a slightly higher max RPM due to the faster value return). I also had the engine case bored to accept slightly larger pistons, 90.5mm bore instead of the stock 85.5mm. Combined with the stock 69mm stroke this increases the engine's displacement from 1584cc (quoted by VW as the "1600" engine) to 1776cc. I also went with a Scat racing cam, which will provide slightly higher lift and let the engine breath better. With this I also installed new connecting rods, lifters, oil pump, and all new seals, bearings and gaskets.
I considered getting the case cleaned ultrasonically, but due to budgetary and time constraints, I decided to soda blast the case myself. I bought a Harbor Freight soda blaster (read -- a shitty soda blaster), and got to work. My family's air compressor (which we've had since I was a toddler) was vastly too wimpy to provide the CFM's that I needed, so a neighbor let me use their huge fifty gallon compressor. I still had a little trouble with oil and/or condensation in the air which kept gumming up the blaster, but I got through it. I was absolutely covered in baking soda after doing this in the hot Georgia summer. I got really sweaty and the powder stuck to me like glue. Here's what one half of the case looks like after blasting compared to the unblasted side.
I made sure to plug up the oil galleys, since I wasn't sure if I could ever get the particles out of there, and I made sure to be careful around the bearing surfaces, which I didn't want to mar. You can reclaim the baking soda and pass it through a sieve if you'd like to reclaim it, but I threw it away since the stuff I was using was relatively cheap. Here's the absolute mess I created in the driveway.
I don't have any pictures of the process, but after blasting I washed out the case with a lye solution to make sure that all of the blasting medium was cleared out of the case. I also hand cleaned most of the the inside of the case with a solvent and some shop rags. You really don't want any grains left in the engine, this is honestly more crucial with sandblasting, since the sand won't dissolve in the oil, but I think the baking soda can also cause some damage before it dissolves or is caught in the oil filter. Either way, I didn't want to take any chances.
Not much to say here. We had a workbench in the garage that was perfect for building the engine on, but it was cluttered and poorly lit. I cleaned the surface off, organized the tools, and installed a little shop light below the cabinetry above. In the photo you can see the great little book that was guiding me through the whole process. How To Rebuild Your Volkswagen Air-Cooled Engine.
Obviously, I was really skittish about almost everything during this entire process, I probably annoyed Clyde a bit too much during this process, as I was calling about really small things, such as tiny surface scratches on my timing gear. He did a really good job of keeping me calm and directing my eyes to the prize. I inspected any crucial metal parts I was reusing, and I spent the better part of an afternoon scrubbing nuts and bolts with solvent and cleaning them up on the wire brush. I launched a good number of nuts across the garage.
From here I essentially followed the instructions outlined in the book. First came the connecting rods. I used plastiguage to check the bearing clearance to the crank. You put a little strip of plastic between the bearing and the crankshaft, torque the rods to spec, remove them, and then it's final width tells you the clearance between the two surfaces.
Before final attachment of the rods, I put the crankshaft and timing gears on, in arguably the most stressful operation. The gears have to be heated in an oven to stretch them out, and then placed on in the correct order and orientation. I probably re-read the passages in the book that described this operation ten to fifteen times before I felt confident enough to attempt it. This operation requires specific pulling tools to reverse, so I didn't want to mess up this step. After these parts are on, then the rods can be attached and torqued to spec, which completes the assembly of the crank. There are still some spacers, a bearing and a oil slinger that must be placed onto the crank, but I waited until the crank was placed into the case to put these parts on. Do not forget to insert the pulley key. I did, and it caused me lots of headache further down the road since it is almost completely inaccessible after the case halves are mated.
I think here is where I really realized how much work I still had ahead of me, which caused my pictures to become less frequent and more sloppy, so, apologies for that.
I prepared the right side of the case (passenger side) on the workbench. This involved placing the lifters into their seats, prepping the lifter surfaces with the lapping compound (a slightly abrasive compound that helps the camshaft mate with the lifters during first operation, note, you do not want this compound on any other surfaces inside the case), inserting the bearing pins and bearings into their seats, inserting the cam bearings, coating the rim of the case with an aviation grade gasket making compound (Permatex Aviation Form-A-Gasket No. 3) and inserting the cam plug.
There is much debate about the gasket compound, RTV is strictly frowned upon, most people go with this Permatex stuff. I actually visited a specific store near Atlanta to pick up this tiny bottle of nasty stuff. Any silicon based sealant is avoided because the case halves need to be sealed, but not spaced very far apart. It's also very difficult to get off if you mess up, which creates even more of a headache. Before applying the sealant, I scraped the surface lightly to remove any last remnants of the previous gasket maker, and finished off the cleaning with acetone to remove any of my hand oils. I made sure not to get gasket maker on any of the bearing surfaces.
I had lots of small challenges during this part. I was very nervous about the quality of the bearing seats in the case. I sent lots of photos to Clyde to make sure everything looked okay. There was some black and brown streaks in some of the bearing seats but I couldn't feel any ridges or scarring. I also had trouble identifying which cam bearings went in what slots, it was very ambiguous and took a while to figure out. Applying the case sealant was also really stressful, it's very tree-sap like, it gets everywhere and it doesn't come off easily.
Similar steps were carried out on the left side of the case, inserting the lifters and bearing pins, inserting the spring-loaded oil galley valves (they keep cold, high-pressure oil from flowing to the oil cooler until the oil warms up a bit to drop the pressure), and checking the lateral clearance between the cam bearing flanges and the camshaft. With some help with my mom, I placed the crank into the bottom half, making sure the pins lined up into the bearings that were slid onto the crank. I also inserted the distributor shaft at this point. This can be done after the case halves are mated, but it requires a pulling tool to remove if not inserted correctly. It's semi-critical to ensure the gear is mating at the correct place, as you want the shaft to be somewhat in the right location. Timing adjustment will rotate the body of the distributor slightly, but the gross placement is set using the mating of these gears. The little gaskets that go on the case half studs.
I applied the lapping compound to the lifters and installed the camshaft. You have to make sure that the cam gear on the camshaft is mating in the right position with the cam gear on the crankshaft. There are dots to assist with this. If this part is not correct, even if the alignment is off by one tooth, the engine will most likely not run. This placement ensures that the cam is in sync with the crank, since the valves need to open at the correct point in each stroke. After one last check, I mated the case halves and installed the studs.
In this photo, you can also see the little bronze fitting that Clyde installed in my case. This is a popular modification that allows for an external oil filter to be installed. A plug is installed in the outlet of the oil pump body, and a custom oil pump cover is placed on the oil pump which has another fitting. The oil is forced out the cover, fed through an external filter, and then flows back into the engine through the bronze fitting that was installed on one of the oil galleys. This should vastly improve the life of the engine, as stock, the engine only has a coarse strainer which captures large objects. Of course, this is almost useless, as large objects in the strainer almost certainly signify engine death. I bought this kit from Gene Burg Enterprises, it came with the oil filter mount, a filter, and braided tubing to wire everything up. Here's the oil pump body being tapped to accept the NPT plug.
I did make one mistake when installing the oil pump. It takes quite a bit of force to squeeze the pump body into the space left for it when the two case halves were mated. The assembly guide recommends a block of wood and a hammer to ease installation, so that's what I did. I reached a point of high resistance and figured it was normal, until one corner of the flange on the pump body broke off. I backed the pump back out and found a bolt head shaped divot in the back of the pump, which means I was hammering the pump up against the camshaft gear. I called Clyde and quickly figured out that I needed to install a lower profile pump because I had used a different profile cam gear. I purchased the new pump from Clyde, re-tapped the new outlet port, and installed the pump.
Next the pistons were partially inserted into their cylinders before the cylinders were slid partially onto the studs to allow for the wrist pins to be inserted. Very important and difficult to get right was the rotation of the three rings. I read a bit on the subject and went with Clyde's recommendations. You want to align them such that no opening is at the bottom (closest to the ground), since this would allow oil to seep through between the rings when the engine is stopped, creating smoke during each engine start. I also made sure the rings weren't all aligned with one another, as this would increase the chance for blow-by.
Before final piston installation, the deck height of each cylinder was measured using feeler gages and a piece of metal across the top of the cylinder. The data on each cylinder was recorded and was used to determine which metal spacer should be placed below the cylinder. This, combined with the measurement of the CC's of head allowed for the calculation of total displacement of each cylinder. Different metal spacers adjust the deck hight up and down and allows for the compression ratio to be set. This is critical. For final installation of the cylinders, I put gasket maker around the bottom seat of each cylinder, this is recommended but not necessary.
The pushrod tubes and their seals were sightly expanded (they work almost like a bendy straw) and then placed into their seats in the case with some gasket maker. Gasket maker was also placed on the pushrod seals that mate with the head. The head could then be installed and torqued, making sure that the pushrod tubes are seating well into the head. This process (final installation of pistons and cylinders (not the measurements), pushrod tube placement and head installation) was then repeated for the other side of the case. (The photo with both heads installed is from a little later in the build, but it fits here as well)
I had previously disassembled, cleaned, assembled and re-oiled each rocker arm assembly and stored them oiled in bags. These were installed, along with the pushrods, into each head and torqued to spec, making sure that the "wavy washers" were oriented correctly. This should help prevent the nuts from backing back out due to vibration.
I briefly considered ordering new engine tin, but considering the cost and the time frame, I decided to paint mine. I was going to use the soda blaster to strip the old paint and any rust, but after remembering my previous experiences with it, I decided to take it to a local sandblasting shop. They took the paint, oil and rust off of all of the tin in an hour for about fifty dollars. Well worth it. I also them blast the exhaust, intake manifolds, heater boxes, and alternator stand.
After I got the parts back, I setup a very janky paint booth in my basement with some plastic sheeting for the walls and butchers paper for the floor (to my parents' dismay) and hung the parts from the ceiling. I made sure to use masking tape and wads of newspaper to block off any holes I didn't want to get paint or primer into. A fan was also placed in the window that was in the "booth" and was used as an exhaust fan to keep the fumes out. I used a high temp primer and paint from the auto parts store for all of the parts, and for the muffler and heater boxes I used an extra high temp "flame proof" primer and paint. Not sure if this was totally necessary, but I didn't want to risk it. This process was a little cramped, I felt like a contortionist attempting to squeeze around all of the wet parts and not nick the paint with my clothing. I succeeded for the most part, but I wish I had more time so I could have done the parts in a rotation. I ended up with paint on almost every part of by body, which didn't come off for a day or two.
Next was the assembly of the top-end. The first thing to install was the pulley wheel. I realized a critical error here, I had forgotten to install the key in the crankshaft that mates with the pulley wheel. Now that the case halves were mated the keyseat was located inside a flange in the case, which makes it difficult to put force downwards in the key to seat it. I thought about using a punch and using the flange as a lever to exert force downwards onto the key, but I was worried about marring the surface of the case. I was able to insert the key by hand and some careful tapping with a hammer and a piece of rod, but couldn't get it to sit level in it's seat. A family friend / mechanic gave me a great solution, just put the pulley wheel on and let the keyway do the work. This worked perfectly, I was able to use the bolt that holds the pulley on to slowly push the pulley onto the key and let the problem work itself out.
I installed NPT caps into the holes that were drilled and tapped in the case by Clyde when he modified my case for the full flow oil system. He drilled these holes in order to evacuate the oil galleys of any stray metal shavings that may have been left behind by the tapping of the main oil return galley. These shavings would cause havoc if present, especially during initial start up. These tapered NPT threads are really stressful, it's difficult to know when you're tight enough to keep the seal liquid-tight. If the cap is too loose it will create an oil leak, and if you attempt to over-tighten them you can strip the thread, or crack the engine case. You can also see the oil pressure switch and pulley installed in this photo.
Now things started to just bolt on to the short block. Next was the fuel pump (stem, shaft and pump body), intake manifolds (the heat riser, rubber boots, and manifolds that bolt to the heads), alternator stand / oil filler tube, oil cooler, heater boxes, muffler, valve covers, and most of the tin above the heads and cylinders. My parts were all a little bent, so they took a little convincing with the assembly hardware to pull them together. The most difficult part was getting the heat risers (part of the intake) lined up with the muffler, because the muffler also has to connect to the heater boxes (connected to the rear cylinders), line up with the exhaust ports on the front cylinders. Further complicating this process are the little pieces that are slid over the exhaust header on cylinders two and four, which have to be situated to connect with the fresh air ports on the front of the heater boxes. This process involved a lot of loosening and re-tightening parts to do fine adjustments.
Next was the carburetor, which I didn't rebuild, but annihilated with carb and choke cleaner before attaching it to the engine. I attached the fan and cover plate to the alternator shaft and inserted it into the fan shroud and attached the fan shroud to the engine. I installed the coil on the fan shroud, and connected all of the plug wires, leaving the spark plugs loose in their respective holes (before the first startup, the engine is cranked without the spark plugs attached to build up oil pressure). Not shown in the pictures is the flywheel which I touched up the surface of using a high-grit abrasive sanding pad on a right-angle pneumatic sanding tool. The right angle allowed me to make sure that I was sanding mostly parallel to the surface of the flywheel. A new flywheel seal was inserted, and the clutch plate and pressure plate were attached to the flywheel using a plastic alignment stick (basically a really short transmission shaft with splines on the end) which ensures that the clutch plate is centered in the flywheel and pressure plate. I also installed a new throwout bearing, because they're relatively cheap, there's really no reason not to at this point, mine was rusting from being in my driveway for almost nine months, so it needed to be replaced.
My dad and I jacked the car as high as our paltry hydraulic jack would allow, and then inserted these ramps under the rear wheels as a precaution. Our jackstands were unable to reach the frame with the car at this height, we could have put the jackstands on some wood blocks, but we weren't going to be getting under the car with it at this height, and we felt the ramps provided enough protection. The engine was rolled out of the garage on a cart and, with a slight tilt to allow the fan shroud to clear the rear body panel, moved under the car.
At this point, we took the alternator pulley off, it became clear that the engine wasn't going to clear the hole in the body without doing so. Then the car was slowly lowered onto the engine, making sure that it lined up with the transmission bell housing. We had to tilt the engine towards the back of the car to let the transmission shaft clear the pressure plate and then tilt it forward to slide the shaft into the engine. It took a pretty good push to get the shaft to seat fully. The jack stands were placed under the car at this point, which allowed me to get under the car and install the four mounting bolts. By far the most painful are the top two, which are very difficult to locate. Your head doesn't fit too well up in the space where they are located, so they have to be inserted mostly by feel.
I stopped taking pictures at this point. The engine was inserted into the car the day before I needed to leave up to Baltimore, and I ultimately did not finish the installation before having to make the trip with my dad's car. Before leaving I did manage to get almost 99% of the final assembly done, there just wasn't enough time to break the engine in and make sure it was in working order before making the drive, and even then, I wasn't too keen on having the first long drive being one that absolutely needed to be completed. Before I left, I connected the fuel lines, installed the last bits of engine tin inside the engine bay, installed the throttle cable and throttle cable guide tube, installed the oil strainer air intake and oil pressure relief tube, and mounted the external oil filter mount to the frame. As I was leaving, it was pretty incredible to look at the table that started covered in parts to see how far I had come.
My dad was generous (and crazy) enough to drive the car up to me in Baltimore on a U-Haul car carrier a week later so he could retrieve his car, which I had drove up from Atlanta. We completed the final work on the car out of a garage which is included in the apartment I'm subleasing. This included connecting the braided steel tubes to the external oil filter, connecting a few electrical components in the engine bay (alternator, fuel cutoff solenoid, electric choke, coil and oil pressure sender), and connected the starter. We even met a new friend, Noah, who I saw driving his E30 BMW through the garage area and gave the cool car head nod to. He came over and helped my dad and I sort out the starter wiring.
At this point, we filled the car with oil, put some gas in the tank, adjusted the static timing (timing at full-advance can't be adjusted until the engine is running), and set the point gap. As mentioned earlier, the engine was cranked without the spark plugs inserted until the oil pressure light turned off, which ensures that oil has circulated throughout the engine. After this, the spark plugs were torqued down and the engine started right up! We followed the break in procedure outlined in the book, a procedure which is highly disputed, it involved running the engine at a constant RPM for about 20 minutes. At this point the car was ready for a drive. You can see a video of the first startup here, along with my excited / sweaty face. Also in the video you can see the timing light I used to set the full advance timing and a tachometer temporarily wired to the ignition coil in order to maintain the RPM outlined in the break-in procedure. After this, an oil change was done to clear out any of the metal particles generated during the break-in process. Also in this first oil change, the lifter lapping compound is mostly cleared out of the engine. After the engine cooled, the valves were adjusted again, and then the car was ready to drive! I've been driving the car very rough these first few hundred miles, in order to break the piston rings in. I followed Clyde's advice and basically put the car through repeated cycles of full-throttle accelerations and hard engine braking.
The car was initially running very rough and it was impossible to fix, which made me very concerned. I made sure all of the tune-up items were in perfect order, mainly point gap, and spark advance, and I just couldn't get the gremlins out. The idle was very rough, and the car didn't want to maintain speed on the highway, really heartbreaking stuff after putting so much work into it. I left the car at work overnight after my drive to work one morning was particularly rough and returned the next day with more tools. Stabbing in the dark I decided to use an automotive meter to set the dwell angle, instead of setting the point gap. The dwell angle is the number of degrees that the distributor shaft turns between when the points close and when they open again, which is directly related to the gap that would be set when the points are in their "full open" position. I was getting very inconsistent and erratic measurements on the meter. The number was dancing around on the meter, and the adjustment of the points gap, bigger and smaller, had almost no correlation to the new reading on the meter. I was at a loss, until I removed the points for inspection to find that one of the contact points on the arms of the point assembly was completely missing.
One set of new points and a timing adjustment later, and the engine was idling smooth as butter and running like a dream. I couldn't be happier. Honestly, this has been one of the most challenging, scary and fun things I've ever done. It felt like every day of work had a new hurdle to jump over, but the payoff has been pretty incredible. I'm so excited that my bug is back on the road and I'm finally able to drive my car again. Unfortunately now, since I'm now 100% responsible for the engine and its maintenance, if I'm ever stranded I only have myself to blame, which should be interesting. Hopefully though, with consistent maintenance (and love and care) the engine continues to treat me well for years to come. Send me an email if you have any questions about the process and I'll be willing to help you in any way I can!