1988 Auto to Manual Swap

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WISE9UY
Posts: 112
Joined: Sun May 29, 2016 5:17 pm
Location: Westfield, IN

1988 Auto to Manual Swap

Post by WISE9UY »

Hello All,

I think I have decided to dive in and convert my 1988 Auto 635csi to Manual. I have found a couple write ups on the topic that address the electric side of things for an earlier model. Included in that article was the Neutral Safety Switch delete, reverse light switch addition and the cruise control fix.

I have a getrag 260 to go in, propeller/drive shaft, cross member, new gearbox mounts, standard flywheel, clutch, pressure plate, new giubo and pedals. I will get new master and slave cylinders and will make up new lines as needed and will get a fluid reservoir.

Is anyone aware of any good write-ups or have any input as to issues to avoid? Specifically when dealing with these later 88/89 cars.

Thank-you in advance for any input.
------------------------------------
1988 M6 / 1988 635csi 5sp / 1986 635csi 5sp / 1986 635csi Auto
1989 325i 5sp / 1987 325is 5sp
1973 3.0CS / 1970 2800CS
2000 323i Touring
Gone but not forgotten:
1970 2002 / 1996 M3 S50B32 / 2009 M3 / 1979 528i
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Brucey
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Location: Cambridge, UK

Re: 1988 Auto to Manual Swap

Post by Brucey »

you don't need a complete new pedal box necessarily; new pedal arms will go into the extant pedal box. Don't forget the clutch pedal spring compensator that fits into the pedal box.

Also you probably don't need a fluid reservoir for the clutch; the extant reservoir for the brake usually has an extra spigot on it; this is designed to feed the clutch MC.

Re the wiring; you just need to connect the reversing light switch wires from the gearbox into the harness plug that the auto gear lever plugs into. Bridge two pins in the same plug to allow the starter to be enabled.

One of the things that is worth thinking about ahead of time is if you are going to be happy with the standard gearshift or not. The standard linkage will be OK if all the bushings are play -free. There is a little buffer in the knuckle joint on the back of the gearbox; it is wise to replace this with OEM (although it is also possible to make steel spring to do the same job that won't rot if it gets oil on it).

One of the annoyances with the standard shift lever is that the throw is quite long; you can get alternative levers (eg a Z3 one) that gives a shorter throw (and higher force obviously). However all BMW gear levers are , it seems, really designed for LHD cars; IMHO they suit RHD cars better if they are cranked slightly rightwards, which is a simple mod.

cheers
~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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86_6series
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Posts: 1069
Joined: Mon Apr 02, 2007 10:08 pm
Location: West Nyack, NY

Re: 1988 Auto to Manual Swap

Post by 86_6series »

If you go with a short shift kit and decide for the selector rod (635CSi) not an M.
You'll need PART#: DSSR189 not PART#: DSSR147

https://www.bavauto.com/usse5l

This one

http://store.uucmotorwerks.com/dssr---d ... -p470.aspx

and make sure to get ADD SELECTOR JOINT p/n 25117503525

Not this
http://store.uucmotorwerks.com/dssr---d ... -p359.aspx

Sometimes this was installed from factory even with auto trans. You'll need this if you don't have.

https://www.bavauto.com/ssk-ik-mid
86-635CSi
96-MB C220 SOLD
98-740i
71-Continental MK3
WISE9UY
Posts: 112
Joined: Sun May 29, 2016 5:17 pm
Location: Westfield, IN

Re: 1988 Auto to Manual Swap

Post by WISE9UY »

Thank-you both for your replies!
------------------------------------
1988 M6 / 1988 635csi 5sp / 1986 635csi 5sp / 1986 635csi Auto
1989 325i 5sp / 1987 325is 5sp
1973 3.0CS / 1970 2800CS
2000 323i Touring
Gone but not forgotten:
1970 2002 / 1996 M3 S50B32 / 2009 M3 / 1979 528i
LarryM
Posts: 142
Joined: Sat Jul 13, 2013 3:19 am
Location: Camarillo, CA

Re: 1988 Auto to Manual Swap

Post by LarryM »

It would be a good idea to install new seals (input shaft, output shaft, and selector rod) before installing the tranny. You don't want to finish the swap only to discover that you have leaks, and it's much easier to do on the bench than once it's in the car. Bentley describes the procedure. Most serious leaks seem to occur at the output shaft. I was advised that when reassembling after installation of the new output shaft seal, apply Curil K2 sealing compound on the internal splines of the yoke (NOT on the output shaft splines) and on the output flange nut.
1985 635CSi
1987 535is
1965 Impala SS
WISE9UY
Posts: 112
Joined: Sun May 29, 2016 5:17 pm
Location: Westfield, IN

Re: 1988 Auto to Manual Swap

Post by WISE9UY »

Thank-you Larry... Indeed wise words and I already had the complete seal kit in advance of this. As you say, the last thing you want is to have to pull it out to fix a leak shortly after installing!
------------------------------------
1988 M6 / 1988 635csi 5sp / 1986 635csi 5sp / 1986 635csi Auto
1989 325i 5sp / 1987 325is 5sp
1973 3.0CS / 1970 2800CS
2000 323i Touring
Gone but not forgotten:
1970 2002 / 1996 M3 S50B32 / 2009 M3 / 1979 528i
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