The weather, while not balmy last night, was at least tolerable in three layers and flannel lined jeans. The main thing was to keep moving, pushing, pulling or otherwise performing actions that burned calories and generated a little internal body heat. The task was simple, though with lots of individual jobs: prepare the engine to be removed. None of these tasks are hard, or even especially time consuming...when all of the fasteners are well lubricated or haven't been left to sit and calcify, rusting into a solid lump of red oxide with no trace where the slot or bolt edges were. But in those cases, I have seen three situations and solutions:
1. The bolt or screw is just simply tired and has spent too long in the same place. A 'little' corrosion has formed between the bottom of the head and what it holds down, or deep down in the threads. That 'little' corrosion is going to make the fastener want to act like it is welded on.
Solution: Leave your WD40 in the closet, and put the 3-in-1 oil away. This calls for something that has all of the wicking power of acetone. PB Blaster is its name, and it smells like being down-wind of a disused fracking facility. But I have found over and over that a touch of this elixir on a bolt that seems welded into place will, when augmented with patience over a day or three, cause many otherwise hopeless cases to release. But for heaven's sake, don't get any on you, and if you might, wear clothes that you have no intention of being seen in after you leave the garage. This stuff is potent, in both the efficacious and olfactory senses.
2. The bolt or screw has been painted over. Great for keeping the rust out, but lousy for removal, since the head has essentially been 'glued' to the contact surface. Also, internal-wrenching heads (Phillips, Hex, Torx, Slot) tend to be filled with the paint, which hardens and makes it very difficult to fully insert the driver into the head socket. In the case of Phillips, which is specifically designed to prevent over tightening by causing the driver to jump out of the head ("cam-out") when the head is resistant to turning, getting painted is almost a worst case scenario, because much torque must be applied to get the shaft to back out, overcoming not only the design intent of the Phillips drive (cam-out), but also the reduced depth of the drive socket AND the increased resistance having been glued in place by the paint. Ugh.
Solution: Believe it or not, a dollop of paint stripper in the bolt head socket and around the edges of the painted head is just the thing for breaking these poor unfortunates loose.
3. The socket (or relief cut, or broach on an internally wrenched bolt or screw) may already have been buggered up (a horrible and accurate word) by someone trying to muscle it into place or out.
Solution: Do your darnedest to get it to back out and if the threads are shot, drill it out and try an easy out. Failing that, I sometimes take a cut-off tool to the edges of the head, making two parallel flats on either side of the head which I can then get vice grips clamped on to. At this point, unless the threads are simply rusted solid, it IS coming out.
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| The idiotic number of fasteners required JUST for the rear engine mantling. The arrows in red are easy to get at, but often rusted solid. The grey ones are both tough to get at AND rusted solid. |
So I got on with the job last night, disconnecting the voltage regulator, the vent fan, the ballast resistors, as well as the power cabling to the battery, the starter, the coil, and finally the Air Flow Meter (AFM) and the Electronic Control Unit (ECU.) I disassembled the vacuum hoses I'd been so careful to assemble two weeks ago for testing and disconnected all of the hoses to the Decel unit that is bolted to the fuel tank firewall. With the hoses and the S-Boot removed, and the airfilter assembly out, it begins to feel roomy by comparison with its normal inaccessibility. While underneath disconnecting the starter, I tried the thermostat bolt that I had treated with PB Blaster three days previous. The thermostat is not the most stable thing to try to twist against (it is a bellows that isn't designed to be torqued quite so agressively. It has also failed, making the bellows even more prone to sagging open. (Yep, another $100 or so. These are no longer mass manufactured, though there are some enthusiasts who have had new ones fabricated by the original supplier. I suppose I should be grateful that they're available at all, at any price.)
The last items were disconnecting the throttle cable, and then trying (vainly) to budge the heater control cables. SNAP! The left hand cable let go at the lug, rather than the nut breaking loose. Add it to the pile of replacements: 211711629N $20. The right hand was already disconnected.
At this point I had disconnected all of 'plug n tug' connections, so I began on the starter. I got the bottom bolt loose and then had to be reminded that this was a year with the 'D' head bolt that is attached by the bolts at the engine side, rather than the transmission side. I locked on to that bolt at the engine side with an open end wrench and despite popped veins on my part it went...nowhere. The lower bolts took some steady strain to let go, but not much grief: they had apparently been tightened to spec the last time the engine was out for a clutch (circa 1997 if the paperwork is to be believed.) Just for kicks, I tested the bolts for the transmission nose cone support. Those are unlikely to have turned since manufacture. They happily broke loose at about 50ft lbs. I'd estimate. Amazing.
I had two final jobs: The first was to try the screw heads that hold on the rear mantling so that there is no interference when the engine is unbolted and pulled back from the transmission. This is where I discovered that all of them appeared to be almost permanently affixed, and doubled my resolve to replace every Phillips or 'cheese head' bolt possible with a broached head bolt. Nuts to this.
The last job was to test the vacuum solenoid on the air filter housing. A brief description is in order: VW used to dump the captured gasoline vapors coming off of the tank into a carbon canister which was immediately re-pressurized by air from the cooling fan when the engine started. The trapped gasoline vapors were routed into the carb for burning, which was better than just dumping them out on the ground. (The hazardous, wasteful and idiotic methods used prior to the 1968 models.) Unfortunately, this tended to cause the engine to over-rich when it was likely already hot and would have a difficult time starting in an already enriched condition. (Gasoline is most prone to vaporize the warmer it gets. Think of a hot tarmac parking lot in August...in Texas. Lots of vapor, and no where for it to go.)
The EEC valve was added to the LJet engines as a means by which the saturated charcoal in the EVAP container could be purged into the engine slowly without swamping the engine with a lot of unmetered fuel. The EEC valve on the air filter housing was connected to the vacuum signal generated by the intake air plenum, which only presented when the engine was under heavy load or acceleration. So you start the engine in that Texas parking lot and the EEC stays closed. Put it in first gear and drive away, you suddenly generated a whole WAD of vacuum, which advances the spark at the distributor, and at the same time, clicks open the EEC valve, allowing the captured fuel vapors to be purged into the intake stream when precision metering doesn't much matter, e.g. under heavy acceleration.
Unfortunately, since the Ljet system is predicated on having 100% awareness of all intake air, any vacuum leak is catastrophic to the running tune of the engine, as well as the leaned out condition of the fuel-air charge that causes exhaust valve temperatures to skyrocket. Since the EEC is 'yet another place you can leak from' best make sure it is working correctly, and holds vacuum. So I did. Hooked up a 1 meter length of vacuum hose, brushed off the other end, stuck it in my mouth and gave a pull on it. CLUNK. Good, the diaphragm in the EEC valve is working. I'll stand here for 30 seconds with the hose stuck to my tongue and see if we hold vacuum or if we're leaking. Nothing. Pull the hose off my tongue: CALUNK.
Smile. I just avoided taking two hours to hand fabricate and seal a replacement vacuum valve for the EEC. All things being equal, a great evening. Next up... increasingly aggressive treatments shown above to deal with the some ten or a dozen glued on bolts that need an attitude adjustment.
After these items are done, I will need to stop work and again perform a pick-up clean-up on the garage to put things in good order before dropping the engine. Once it is out, there are going to be increasing numbers of components floating around the garage, so I need to have systems, procedures and/or rituals in place to deal with the excess.
The only remaining components (according to the Bentley Workshop Manual, and the much more shade-tree centric ratwell.com) I have only to complete the following:
- Dump oil & filter (DONE)
- Rear mantling out (DONE)
- Brake Hose check valve, disconnected
- Oil filler remove (plug with shop cloth so debris does not enter) (DONE)
- Remove the rear bumper (17mm bolts, use impact wrench) (LOOSE)
- Complete removal of the starter (D bolt on the top right side of the engine.) (LOOSE)
- Remove LH pushrod tube cover (REMOVED)
- Break loose rear carrier bolts from bottom of engine as well as from chassis (PB Blaster likely) (LOOSE)
- Break loose other three engine to transmission bolts (17mm) (LOOSE)
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