Manual Swap Questions

[LateFan]

Wow, it is not an easy task getting that automatic out of there. 3 1/2' of extensions from the tailshaft along the top of the tranny, a wobble, and the reverse torx socket on blind bolts. If the assembly is tilted back, the head is against the firewall padding and there's no room for fingers or to see in there. Then I misjudged the center of weight of an auto trans and had some plywood and the jack on the flat pan, and it was really nose heavy.

On a positive note, all the exhaust nuts came off with a just a 1/2" ratchet, and everything underneath was easy to remove.

Yes, we dumped ATF all over the floor and everywhere!

I'd like to see how the factory mechanics do this. And what is the reason for the star heads on the bell housing bolts?

[ForcedFirebird]

The reverse Torx head bolts are so you can get a socket in there. If you were to use a hex cap, the socket would interfere with the bell housing, and if you use socket cap screws (conventional allen heads), then the socket will get jammed between the trans tunnel and trans, so the bolt can;t make the turn to get out of the car.

Ask me how I know? People being "wise" and using store-bought bolts on their bell housing, then dropping the drive train in whole - only for me to have to remove later. Sure, it works fine out of the car, but in......

Just like those pesky "exhaust shops" that weld the entire exhaust in one section, so it's not serviceable without cutting/welding, grrr....

[LateFan]

It occurred to me the dealer guys probably pull the whole engine/trans assembly and never fight this.

So is it the same frustrating exercise getting the bell housing bolts back in, or is the case smaller and there's more room up top?

One thing that helped was to wrap some tape around the 3/8" u-joint so it wouldn't flop around or hang down when you're trying to guide it onto a bolt.

[ForcedFirebird]

The manual has more room. Yes, during assembly, the chassis is dropped on the sub frames, but they do have to make sure the car is serviceable.

I find that leaning the engine back helps a lot for the bolts, specially the starter and top two bolts.

[tomstin]

This helped me: https://www.pelicanparts.com/BMW/tec...ch_Replace.htm

"In order to remove this top bolt, I used the following tool combination: 3/8 Torx socket, 3/8 1-ft extension, 3/8 extension u-joint, 3/8 3-ft extension, 3/8 to 1/2 adapter, 3-ft 1/2 breaker bar. This combination of tools was the only way I could reach the topmost bolt and remove it."

And, as ForecedFirebird mentioned, tilting the engine back a bit. Also, I loosened the sub frame bolts a bit which give you another 1/2 inch or so, but be careful not to loosen them too far!!!!!

[LateFan]

Interesting idea - yeah, not too far! Thanks. We have new motor mounts and a starter to put in while we're here. Between our work schedules and a 95 degree garage in the afternoons, we're getting over our exhaustion and planning the next steps. Pedal assembly, clutch master, plumbing, finish the new seals on the manual, and then get started lifting it up there.

One of the torx head bolts seems to be way short in the new transmission. As we took them out of the auto, we put them in the correct hole in the manual so we could keep track of them. The one at the casting for the crank positions sensors is like a quarter inch short of even making it out of the hole. So either the cases are different, or we mixed up two bolts. I'll look at the parts diagram. Too late to order factory bolts now I think - this thing has to be in and functional by this weekend. He's driving across the country in two weeks.

The last of the back-ordered parts showed up this morning - that sponge-shaped foam sound block that sits around the base of the shifter. I'm still not sure the shift lever will clear the hole in the tunnel if you install the shifter assembly first.....?

[LateFan]

Question - Slave cylinder on the bell housing BEFORE you install the transmission, or after it's in place? I thought I read the fittings are really hard to get to once the tranny is in.

And the shift lever question - put it on now? The shift lever is already assembled, but I could pull the top off if needed.

[tomstin]

I would put the slave cylinder in after the transmission is installed. Connecting those hoses with the cylinder on the bell housing will be a pain. Same for the shift lever, as that will be one more thing to juggle while aligning the input shaft.

And a warning, those slave cylinders can be a beast to bleed.

[ForcedFirebird]

IAnd a warning, those slave cylinders can be a beast to bleed.

I have never needed to crack a bleeder on a slave. Leave the slave hanging out of the gearbox, attach the hose. Fill the reservoir, go back under the car and plunge the slave rod in/out several times and you will hear the "squishing" noise as the air goes up the hose and into the reservoir. Bottoming it out several times will clear the lines of air. You will know when it's bled enough when the studs on the bell housing will barely protrude from the slave when there's a little tension to push it in. Now you will have about half pedal, and pumping the clutch pedal a few times will get the last bubbles out.

[LateFan]

Great info gents - thanks.

Well it sure is easier to put a new starter in with the thing open! Sure glad we had the impact gun for those drive plate bolts.

Mechanic writing on the torque converter is evidence this thing has been out before. We don't have record of when or why. Interesting.

We found an oddity where the bell housing casting around the CPS's is thicker on the manual, and one of the smaller bolts won't even reach to end of the hole from the backside. It's the correct length according to realoem. We're double-checking this morning, and need to find one pronto. Stupid to overnight one bolt. If that head is reachable, maybe a hex head in that one spot from local industrial supply. We're down to the wire.

[LateFan]

Yep, that one bolt needs to be an M8x70 instead of 50. Maybe a very early G260 has a different casting at that hole. It's the bolt just below the CPS holes.

[LateFan]

Fastenal local has 12.9 hardness socket head cap screw in M8x70, 1.25 standard pitch (which is what ours is). FCP has BMW M8x70 - comes from a 538, 6 series, 7 series - that ships "in three days," which means they don't have it in stock.

[LateFan]

BMW says there are 4 of those 70mm bolts in the country, and the part # is discontinued. We bought the cap head version. Someday when the clutch wears out we can put the right one back in.

These were really helpful for me to see it all.....pedals - hydraulics - then tranny install, like you guys said. Shifter last.

https://www.youtube.com/watch?v=_rDgYeeFAMk

https://www.youtube.com/watch?v=0COuhfv2z9s

We mocked up the rest of the loose bits in boxes to see if it's all there....


Somebody's been in here before. The torque converter has paint pen marks with "86 BMW" and such, like it was a used part.


This tells me we should go ahead with a new rear main seal. We have the new Corteco (but no housing gasket, where the hell is it? Can I save the old one or use gasket maker?)




That RTV goop on the pan is curious......

Question on the selector rod - do I grease the two pins? I cleaned them up with emery cloth.

[ForcedFirebird]

You can use gasket maker, but realistically, you can change the seal without removing the housing - that's how most other mfgr's do it anyways.

A little grease doesn't hurt, but the busings are actually plastic and should self-lubricate.

[LateFan]

OK, we've made a lot of progress over the last four days. Transmission is in, all bellhousing bolts torqued. New mounts in. New starter in.

***** (Advice for newbies like us doing this - When you rock the engine back with a jack to help align the transmission, make sure your starter solenoid housing doesn't catch on the seam on the bottom of the brake booster, which binds them up and pivots the starter on the front mounting bolt you just installed on the block, which yanks the sheet metal spacer plate on the block UP, and twists the shit out of it! So, don't do that. Took a couple of hours of lining up bolts in the block to fix those points, pulling, prying, tapping, sheet metaling until it was flat again and lined up with all holes. Or, you could take the clutch and flywheel back off and flatten it on the floor if that sounds like more fun to you)

New cross member in, new driveshaft in and length adjusted. New Guibo (I think it's Giubo on an Alfa?) with arrows lined up. Heat shields in (shame to cover up all your nice driveshaft work). Exhaust in, O2 connected. Nice shiny new copper hardware, mmm. Auto exhaust transmission hanger is way back from the new manual hanger - need to weld a tab for that bolt.

Slave bled and pedal feels good, brake and clutch pedals are level. We spent two hours on the computer late one night trying to figure out how the damn clutch return spring I bought hooks up (not the helper spring - a little return spring the diagram says you should have). The best advice I found was r3v people who said, forget it, I don't have one, you don't need it. Another crisis solved.

New pedal pads. We used the wiring guide where you carefully track down the automatic harness, disconnect it, and reconfigure to manual, rather than just cutting and splicing all those wires together at the shifter.. The critical plug we finally found behind the drivers side kick panel, not under the dash. I fabricated a reverse light harness as it didn't come with the tranny. Put it in a snug asphalt cable shielding tube from NAPA and just enlarged the slit in the shift boot a bit. My son solved all the wiring, I was out of my element. No way I could have done this job alone.

A transmission jack is a brilliant tool. You can tinker and adjust and tip it and scoot it closer and closer. If we had tried to horse that thing off the floor, I would have hurt something important trying to hold it and align it and feed in bolts all at the same time.

We did a timing belt at the same time, so all the plumbing, radiator, and coolant has to be finished up. We're drilling holes in the front cross-member for a red46 skid plate.

Interior going back in - we were also chasing some water leaks. Since a generic OE shift knob is like 80 bucks, I'm springing for one of those cool mahogany laminated 917 knobs as his going away present. One week to test this thing and make sure it's ok before a cross-country trip. Will the rear main seal or rear pan flange puke? Will the output shaft seal blow out? Will we find out we were conned and this transmission has crappy syncros and is a pain to shift?

We'll see..........