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Auto to manual swap

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Auto to manual swap

Post by Shushman » Tue Sep 09, 2014 9:40 pm

Hi. i was wondering if anyone on the forum can do a manual swap for me? i dont have much experience in this and would love to learn along the way. i have a E28 520i auto. have a e30 manual gearbox with slave sitting in the garage. was wondering how much it would cost and exactly what parts. i know ill need clutch, shifters, ecu, master cylinder, relevant piping, driveshaft? . im sure iv missed loads. thanks guys and girls.

another option can be a proper guide, and i could tackle it myself (try to). Iv searched far and wide but havent come across a guide that i feel im comfortable with. any help would be much appreciated guys.

Oh and im based in london.

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Re: help with manual swap?

Post by nas80 » Wed Sep 10, 2014 12:02 am

This is kind of applicable for e21's so I thought I would do a write up - obviously not taken any pics.

Get the car in the air, high enough to be comfortable underneath. You will definitely require axle stands, do not attempt this job using jacks, the car WILL fall on you.

Parts list
0.5 - e30 gearbox and shifter mech.
1. clutch pedal
2. Clutch master
3. Some copper brake pipe and a flexi hose
3. A metal tab and spring clip for the copper hose to flexi hose connection affixed to the firewall.
4. some wire
5. The bracket that holds the back of the shifter plate onto the body
6. e30 flywheel
7. e30 clutch
8. e30 pilot bearing
9. Clutch release bearing
10. correct "manual car" flywheel bolts (auto ones are different!!!)
11. flywheel centre plate
12, gearbox mounting rubbers
13., gearbox metal mount
14, manual propshaft
15. new guibo

Start by removing the exhaust, then the gearbox linkage, propshaft and any electrical connections (reverse?)

Once you have everything transmission related off the car (including the shifter) and gearbox cooling lines (take them off the rad)

You need some way of stopping the crank from moving so you can remove the torque converter off the back of the engine. you can use a breaker bar on the front pulley or a flywheel locking tool.

You can now tap the pilot bearing into the middle of the crank - use a socket that is slightly smaller you will know when it has gone deep enough as it will change tone when you hit it as it will be against a ledge.

Take your flywheel and then offer it up there will be a locating collar on one of the bolt holes.

Put the flywheel center plate on, I think the proper name is a "gall plate" but tis just a giant circular washer which all the bolts go through.

Put the flywheel bolts in - you can use locking thread resin. - tighten like you would a wheel. the torque required is 77lbs/ft

Clutch - I use a home made tool, but you can buy proper clutch alignment tool. You wont be able to fit the box if the clutch isn't exactly in the middle, you can do it by eye but it may take you a few goes. Fit the clutch on and pressure plate, the bolts that hold that need to be 25lbs/ft

Stick the clutch release bearing onto the gearbox shaft, you can apply a little bit of lithium grease if you want, (make sure the clutch slave is not attached to the box!)

Fit your new guibo onto the back of the box, ensuring you put the bolts on the correct manner (many guibo changing threads and they are the same for every bmw) and fit your reverse cable

Now the fun part, you need to get the gearbox under the car, I would do this with a friend because you may drop a gearbox on your head and you will be killed and this is a terrible way to die.

Get the gearbox on a jack (unless your both very strong) put it in neutral, then fit it on the engine, you can wiggle the gearbox shaft by rotating the guiboget ready with some bolts, if your forcing stuff too much then you wont get it in.

Once the box is on fit the clutch slave with the flexi attached. Now get your shifter mech and attach it to the car.

You can now line up the bracket that holds it up, you can drill the holes through it and then through the transmission tunnel. it should end up under the center console. To make this a lot easier weld your bolts to the shifter bracket.

Feed your reverse cable through up to the shifter, attach the propshaft to the guibo,

Now you are done under the car you now need to by pass the neutral / park safety switch. there will be a big square plug that used to attach to your auto shifter, there will be two wires at the top half of this plug - I cannot for the life of me remember which they are but you will see on the auto shifter they attach to a switch.

Fitting the clutch pedal. you simply undo the clevis attached to the top of the brake pedal and undo the massive bolt that runs through the top of the pedals. once you have done this the brake pedal will fall out. you can cut the pad down which is an utter bodge or replace it with a manual pedal. stick the clutch pedal on and pass the big bolt through and then do it up. reattach the brake master clevis

Now you will see there is a blanking plate in the engine bay this is undone and then your clutch master goes in through there. fit the clevis to the clutch pedal,

Now its time to run a hydraulic line, there are two schools of thought here, you can measure the distance and then get HEL to make you a line (m10 fittings) or you can make a copper line up and then run it along the firewall and down towards your bracket, if you have a braided line made that is the full length then you will find you wont have to make this bracket but your line must be sufficiently long and secured along the firewall.

Attach the reservoir and then get under and undo the bleed nipple on the slave, you can wait for a bit of help it along by giving it a few light presses on the clutch pedal. Once bled the conversion is complete...

Double check your bolts are on tight, and then go for a drive round the block.

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Re: help with manual swap?

Post by stefankj » Wed Sep 10, 2014 12:23 am

What about speedometer?
1982 315

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Re: help with manual swap?

Post by nas80 » Wed Sep 10, 2014 1:05 am

wont matter in an e28 the speedo drive is in the diff, obviously if your doing this on an m20 you would be using the e21 m20 box which has a speedo drive

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Re: help with manual swap?

Post by jimbob » Wed Sep 10, 2014 1:12 pm

A good way of offering up the gearbox i found was to use a ratchet strap through the doors and looped under the car.
Makes it much easier if your doing it on your own
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Re: help with manual swap?

Post by brennon » Wed Sep 10, 2014 1:55 pm

One of the things I'd say to watch out for is when you push the bearing into the crank make sure you have it square, I came a cropper a few years back when I hammered it in level to the floor without taking into account the engine had tilted with the gearbox removed.

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Re: help with manual swap?

Post by Shushman » Wed Sep 17, 2014 10:52 pm

Nas thank you so much for taking the time out and explaining the whole process. really appreciate it. im going to PM you in a bit. let me know what you think.

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Re: help with manual swap?

Post by e21Keith » Sun Sep 28, 2014 12:29 am

I've done this swap on e30s and e34s. The best advice I can give is to buy a conversion kit from the same model or even buy a donor car. Things like mountings an wiring for the reverse sensor and inhibitor can take an age to fathom otherwise.

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Re: help with manual swap?

Post by Mihajlo » Wed Oct 29, 2014 6:32 pm

Make it Sticky! :thumbsup
Understeer is when you hit the wall with the front of the car. Oversteer is when you hit the wall with the rear of the car.
Horsepower is how fast you hit the wall. Torque is how far you take the wall with you.

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Re: Auto to manual swap

Post by Jeroen » Wed Oct 29, 2014 8:29 pm

Hmmm somehow I missed this one, thanks for the write up Nas, and as suggested I added this to the Top Tech Topics now. If anyone has and photos to add that would be most welcome!
Regards/groeten, Jeroen

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