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Sun Apr 29, 2007
08:27
Well, the ACN transmission I rebuilt is finally installed in our Mk2 Golf. While I was removing the old transmission, it fought me every step of the way. The new transmission went in fairly well, but there were a few hiccoughs along the way. I guess I'll start at the beginning.

A2 transmission removal is possible without removing the engine, and without removing the front axles ... but just barely. It is a tight, tight squeeze and the transmission has to be twisted around into precisely the correct position before it will drop out from the bottom of the car. First, the starter needs to be removed (the engine has to be supported first, since the starter bolts are also the front engine mount bolts - weird, I know), the shift linkage disconnected, the inner CV joints disconnected, the speedometer cable disconnected, and the clutch cable disconnected. You can also make the whole unit a couple of pounds lighter by draining the gear oil first (recommended). I didn't drain the gear oil because I didn't have room left in any of my oil-draining containers. Next, there are two 11mm hex bolts that bolt that tin cover plate to the bottom of the transmission bellhousing. You'll see them at the bottom of the bellhousing, hanging right below the engine's oil pan on that side. They might be completely invisible underneath a heavy layer of grime - so grab a brush and start scrubbing if you can't see them. Other than those, there are only three 19mm bolts left holding the tranmission to the engine block. Two are near the back-side of the engine - one up top that goes in from the transmission side, and one down at the bottom that goes in from the engine side. There is one more on the front-side of the engine, near the top, that also has a ground strap bolted to it. At some point you'll want to support the transmission with something (a jack, or jack stands, or a strong friend).

Next, there are two transmission mounting brackets (one steel, one aluminum) which both come together to bolt down to a single transmission mount on the subframe. One bolt holds them down to the mount, and it's located below the brake master cylinder which makes it kind of tricky to get to. I used an impact wrench with an impact-grade universal joint and a long extension (when you use a universal joint with an extension, always try to get the joint as close to what you're trying to remove as possible - that makes it a little more stable). The aluminum transmission mount needs to be disconnected from the transmission. It has some of the shift linkage fixed to it, so you can either disconnect the linkage from it and remove the aluminum piece altogether, or you can leave the linkage affixed and just swing the piece up on top of the transmission (that's what I did, and it didn't seem to be in the way at all). Anyway, three long bolts hold that aluminum bracket to the differential housing. I removed two from the top (leaning over the engine bay) and one from underneath (laying on the ground). You will need to remove the steel mounting bracket from the transmission also - but it can be tricky. The two bolts holding it in place go through from the side closest to the body of the car, and even after you take the nuts off the opposite end, the bolts will not slide out until you let the transmission drop down so that those bolts can be slid out underneath the driver's side crumple zone. Then the steel bracket can be removed from the transmission. Those brackets will both hit the side of the engine bay, preventing you from completely removing the transmission - so definitely take the time to remove them.

At this point, I had absolutely everything disconnected from the transmission. There was nothing left holding it in place except for fear and common sense (as a favorite saying of mine goes). I spent the next 2 hours trying to remove the transmission from the engine bay. This is where a second person helps - otherwise it is just a physical wrestling match. The key is to rotate the gearbox so that the differential is raised up, and then swing the back side (fifth gear housing side) of the transmission at an angle downard and slightly toward the front of the car. That sounds easier than it is, trust me. The passenger side output flange will want to keep catching on the flywheel teeth on the engine, and the bracket for the front motor mount will want to keep binding against the transmission housing. Removing that front engine mount completely might make things easier - and removing the passenger side drive flange from the transmission would definitely make things easier but could also get pretty messy. I finally worked the transmission out while supporting it with my knees from under the car and then let it slide into my lap. The front of the car was jacked up high enough so that the transmission came out with me as I slid out from underneath the car. ... and that was Thursday night. I needed a shower and some sleep after that nonsense.

Friday after work I wrestled the rebuilt transmission into place, which went much easier than removing the old unit. I had some parts to swap over from the old transmission onto the new one before installing it, but that didn't take very long. All in all, it was about 3 hours until the new transmission was physically bolted into place. I called it a night and cleaned up, counting on getting all the loose ends tied up in the morning. ... silly human.

Saturday morning I resumed work. Did up the transmission mounts, torqued those 19mm transmission-to-engine bolts, installed the starter (and front engine mount bolts), attached the shift linkage, and attached the clutch cable. Before filling the transmission with oil, I wanted to make sure the clutch felt like it was engaging and disengaging properly. Everything felt good, so I added 2 quarts of Redline MT90 through the speedometer cable hole (way easier than using the fill hole on the side of the transmission) and then attached the speedometer cable. I then turned my attention to reconnecting the inner CV joints to the differential output flanges. It was about this time that I realized something major that I had overlooked. The flanges I reused on the transmission I rebuilt were the wrong size!!! This transmission came out of an early A2, and used 90mm flanges. My A2, being a 1991, uses the larger inner CV joints which need 100mm output flanges. I now faced having to swap out the flanges with the transmission in the car, and filled with brand-new Redline oil. Crapola. So I bit the bullet and removed the driver side axle completely (it was the only way to get enough room to operate on that flange), took the 100mm flange off the old transmission, cleaned it up, then removed the small flange from the transmission in the car... then I scrambled to install the larger flange while transmission fluid was peeing out. I didn't want to lose any more than I had to. That stuff is about $10 a quart (if you find a decent deal on it). The other side was a little easier because I could just prop the axle up out of the way rather than completely remove it. In the end I only lost a few ounces of fluid. That whole operation ate up quite a bit of time, though. Now I had correct flanges that would mate up to the inner CV joints. I made sure the transmission was in neutral so that I could rotate the flanges while installing the inner CV joint bolts... but there was a problem. Even with the gearbox in neutral, I could not get the output flanges to turn. Before installing the larger flanges, they turned with little effort. All kinds of terrible thoughts started to go through my head - had something in the transmission popped loose and allowed a gear to engage? Had something in the process of installing the larger flanges caused the differential to bind up? In desperation, I pushed down the clutch pedal and ran the shift lever through the gears and everything felt fine. Now everything was mysteriously freed up. Strange. That made me a little nervous, but everything seemed okay so I continued bolting the inner CV joints to the transmission drive flanges. With that done, I started the engine with the front end in the air just to make sure the clutch engaged and disengaged correctly, and to make sure the tranmsission would actually drive the wheel hubs when it was in gear. Everything was fine - clutch acted correctly, and my front brakes started spinning up like crazy as I ran through some of the gears. Cool. I took this opportunity to install my summer wheels and tires too, since nice weather is finally here.

So now everything was back together and the car was back on the ground. Ready for a test drive. One thing that I don't believe I've mentioned yet is that I rebuilt this transmission using a Peloquin 80% limited slip kit. It takes the factory 20% limited slip and anti-torque-steer effect and increases it to 80%. So in theory, it should now take nearly 100 ft lbs of torque for a wheel to start spinning instead of the factory 25 or so. Anyway, test drive time - and everything was good. Better than good, actually. The transmission is nice and quiet (especially compared to my old one, which had some nasty bearing noise), all the gears engage very nicely, and I'm not leaking transmission oil from my drive flange seals anymore. That whole thing was a real fight, but definitely worth it. I need to do an alignment now, though. The alignment was a little bit out to begin with, and now it's even worse because I had to disconnect the driver's side ball joint to remove the axle on that side. I may do a writeup on how to do your own alignment soon. Watch this space.

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Date: 07/11/07, 05:22:31 PDT
From: OHIOBENZ
Comments: hey - nice write-ups! I hate to say it tho - i used towrestle trannies in & out like that until we learned a couple tricks... my son has one out from start to finish in 45 min now :) BTW - interested in the shelf straps as long as theres no sign of cracks... drop me a line.

Date: 07/11/07, 15:38:39 PDT
From: max
Comments: Thanks OHIOBENZ - I'm sending you an e-mail right now.
A1 parts for sale:
intake air preheater hose
Item: Intake air pre-heat hose (from exhaust manifold shroud to air box), for Scirocco 2 (1982+)
Condition: New
$12


A2 parts for sale:
A2 GTI dual round grill, with inner lights
Item: GTI dual-round grille with inner lights, bulbs, and lower trim strip
Condition: Used, lower trim strip is weathered.
$35

parcel shelf strap
Item: Parcel shelf strap, 3 available
Condition: New
$3.50 ea.

A2 valve guides, 8 valve
Item: 8 (eight) valve guides, German, standard size, for 8 valve head
Condition: New
$24

wheel cylinder
Item: Wheel cylinder (for rear drums, obviously), 2 available.
Condition: New
$12 ea.


A3 parts for sale:
parcel shelf strap
Item: Parcel shelf strap, 3 available
Condition: New
$3.50 ea.


A4 parts for sale:
ALH water pump
Item: OEM Water pump, ALH engines
Condition: Used, 130,000 miles
$20