Too Much of a Good Thing

Sometimes, you can be too aggressive in your attempts to get a leg up on a problem. Examples of this may include bringing a fire hose when only a eyedropper is required, or deciding to use oven cleaner rather than simple green, just because you're in a hurry. As many mistakes are made from over application of effort as under-application.

My bus is up on six ton, 21 inch lift jack stands, which puts the bottom of the vehicle about half a meter off of the ground. This is fantastic, because when you're lying on a mechanic's creeper, it allows you to work with your arms fully extended, which really reduces the fatigue.

Unfortunately, I ran on to a problem with it came time to pull the engine: 

Skids of the ATV lift used to remove the engine are only a 15" lift. The bus is too high off of the ground
for the lift to reach the engine.

So now I'm faced with two options: lower the bus, or raise the lift. I decided not to lower the bus. Some judicious use of 2x4 lumber on the skids raised a surface enough to permit removing the engine.

THAT is one tight fit. Since the lift pivots forward to lower the load, the load moves both down and forward, just at the time when you really don't have much wiggle room front to back. There are so many engine accessories that must be removed just to get the engine to the point of having a bare 12-15mm of space front to rear within the engine bay. So it is almost a wiggling motion: pull to the back, drop the hack half an inch, pull to the back, drop, back, drop, back, drop. Over and over.

The sticking point; the engine is as far back in the bay as it will go, but the bottom studs have not cleared
from where they pass through the transmission housing.

Well, I bent up the end of the oil filler to straighten the engine out enough to get the bottom studs out. But I had to grab the exhaust and lift steadily to change the angle of the engine so that these bottom studs would disengage without bending. Better the oil filler banged up (bolt on replacement) than the studs. (Not so bolt on.)

The input shaft from the transmission has
cleared the clutch disk, but those studs at the
bottom are still not quite free.

I've pulled a few engines in my time, all VW aircooled. My first was a 1600cc TypeI single port from a 1968 Karmann Ghia in 1991, and I've pulled (and installed) six or seven more in the intervening time including a 1971 Bus engine in a parking lot with only a cheap jack and some 2x4s liberated from a nearby dumpster. The Bus engine I did in six hours working by myself from the time the engine was delivered to the parking lot, and drove it to work the next day.

So I would not consider myself inexperienced. Perhaps a dilettante, but not without having run the gauntlet a few times. Perhaps I was more haphazard in my youth and that lead to better work times (and more parts left over.) That 1971 Bus was the all time worst, since I had never experienced fiddling with a rear engine carrier bar before, and didn't really have either the muscle or equipment to do right by it. So I had to invent levers out of those liberated 2x4s to make the engine tip in the directions I needed it to so that all of the fittings would line up.

Engine on the ground, fully disengaged.

So while I won't credit this engine pull as the worst, having the body too high off of the ground and a less than practiced eye for this model and design, I had some "sweat, swear, and try again" moments. But all being equal, it was one hour from beginning the pull to the time that the engine was on the floor and no longer properly part of the vehicle. I hauled it around to the edge of the vehicle, photographed it a dozen different ways for documentation, and then stashed it still on its jack under the workbench so that I would have more swing space to work in the rest of the garage. There is still the fuel tank and the transmission to remove before I get to start putting things back together. Whyfor? Well the engine has to come out to get the fuel tank and the trans out, the tank has to come out to be replaced, and the trans has to come out so I can install $5 of rubber and plastic bushings that have given up the ghost and caused the shifting to feel like a garbage truck, with Ouija board vagueness in gear locations, making the search for second gear more of an epic than it should be.

Progress!

The Horror of a Busted Stud

There is nothing worse than a busted stud. Just ask any heifer.

When the going gets tough, the tough use propane. Really. There is little substitution (when you're not concerned about scorched paint or smoke rolling off of components, oils vaporizing, etc.) for the judicious application of heat when you want to get a fastener's attention.

In this case there are a dozen or so fasteners that need their attitude corrected. They're the Phillips head screws that attach the mantling at the rear of the engine. Because you must pull the engine straight back to disengage it from the transmission, these characters have to come out. They don't want to come out, and all the PB Blaster in the world hasn't convinced them. It's time to bring in my little friend, the propane torch.

I lit up the propane bottle I use for pipe sweating in plumbing applications, dial down the flame to about an inch, and then, having made sure that all pieces of flammable foam, rubber, or other materials are not near where the flame wants to work, I started by playing the flame in a constantly moving circle for a count of 30 around the bolt head. Not on the bolt head, mind you; around. The idea is to cause the metal around the bolt to expand more than the bolt does, making the captive nut that the bolt is screwed into larger as the metal expands. Then I shut off the torch and quickly grabbed my P2 Phillips screwdriver. (Phillips comes in different sizes, and each size is good for a specific torque. If you mismatch the size of the driver to the size of the head, expect to strip the head, or not be able to generate much torque.)

One hand pulling down hard to keep the driver from 'camming out' of the bolt head. The other twisting counter-clockwise as hard as I could manage.

TINK!

The bolt is loose and backs out smoothly. I won't bore you with repeated details: I performed this eleven more times, and all of the rear mantling was out. No cammed-out stripped bolt heads, no bolt heads twisted off. Yea, me.

Flushed with my new success, I decided to attack the exhaust manifold studs. These are legendary for snapping off, stripping off, or the bolts seizing solid. Probably because the engine was designed in the mid  1960s as a 1700cc, 80 DIN HP (8.2:1 CR) for the  VW 411/412 mid-size sedan series (weighing 2468 lbs.) before being adapted into the Porsche 914 and the VW Bus in 1972. By the time my 3042 lb. 1977 Bus toddled into view, the same engine had bore and stroke increased to produce 2000cc displacement, but owing to a lower compression ratio (7.3:1), and increasingly strangling emissions regulations, power output has actually fallen to 68 DIN HP. Torque produced between the original design and the final incarnation was the same, just moved lower in the power curve to help the heavier bus lumber its way up to speed.

I go into all of these eye-chart specifications because it shows how crazy things were at the time in automotive engineering. One of the byproducts of this increase in displacement, combined with lowering of compression ratio, was that exhaust temperatures skyrocketed. For the emissions, this is great. You're going to more completely burn up your fuel and spit fewer horrors out the tailpipe if you've put them through an aggressively hot engine and then designed the exhaust system to keep the temperature up in a long path to the tailpipe.

Unfortunately, one of the other things you burn up in this increased inferno are your exhaust valve seats. The original spec of this engine wasn't built for this kind of abuse, and Volkswagen's policy of using interchangeable parts to solve problems without designing 'whole system' really chewed up engines. This includes little things, too....like exhaust manifold studs. Made of mild steel and screwed directly into tapped aluminum heads, these studs were not engineered for higher heats generated by these engines. At the very least, copper nuts should have been substituted for the equally workaday mild steel nuts that were used. No such luck. So I decided to bite the bullet and as long as I had torch in hand and success under my belt with the mantling bolts, give the hot-foot to the exhaust manifold nuts a try and see if I could get them out without snapping one off.

It was nervous work, but my score was five nuts removed with studs in place, and three nuts frozen on the studs, but the studs backed cleanly out of the aluminum heads, so new studs should be easy to turn back into those threads when coated with some very high temperature Loctite. I discovered some surprises: steel nuts had apparently been replaced at different times, since about half were 12mm and the other half were the stock 13mm. (This is no surprise: the 12mm is much easier to work with, owing to somewhat improved clearance.)

But one nut was clearly larger than 12mm, but when I put on the 13mm, it just thumped around when turning. This is where I felt that 'uh-oh' sensation grow cold in me. A nut that has been so thoroughly abused and corroded that the corners have eroded right off bolt. How are you going to grab this with a socket now?

So I got out the torch again, and this time applied it to the 12mm socket on the end of a foot long extension. I heated the socket until it was smoking hot (there goes the temper on THAT socket!) Then put it over the nut and gave it a couple of mighty whacks with a framing hammer. I felt it hit home and stop moving over the nut on the third whack. When I let go, the extension hung out the bottom of the engine like a surgical instrument left in place. I took a twenty minute break and when I came back, the socket had cooled around this nut, the heat having expanded and stretched it to become "12mm plus some" and then been beaten into place around this rounded off nut. I popped the ratchet on and heaved and it didn't pop, snap or crack. The nut was so thoroughly corroded on to the stud that the whole stud just rotated cleanly out of the head. The socket is permanently attached to it. I don't care. If I have to spend $20 for a new socket set to replace one lousy socket, it is still cheaper than coping with just one busted stud.