Conversion from automatic to manual gearbox.. Part 1

The reasons why I wanted to change from an auto to a manual gearbox were twofold:
1) Automatic gearboxes made in the 1970's were generally speaking horrible and expensive to fix and maintain
2) My gearbox was an unpredictable and fickle thing, its favorite trick was changing gear mid way around traffic islands. This in itself isn't a problem except it usually changed down a gear and in the wet I used to go sideways a lot, fun and probably looked quite impressive power sliding round but not good for the nerves.

Rather than waste a lot of time (and cash) adjusting the automatic gearbox, it seemed easier to pull the engine, switch boxes and drop it back in... sounds easy.. read on.

The idea and how to guide from Don Kennedy's website (www.donkennedy.co.uk) gave me the starting point of what needed doing, the helpful chaps on the RSSOC's Scimitar web forums (www.scimitarweb.co.uk) were very helpful when things got tricky and most of the parts came from a member of the RSSOC, thanks Geraint.

I have attempted to set out a logical path for anyone wanting to do this themselves, it took me all winter but I did recon the engine, gearbox and all of the other bits. I have heard people say that they can do it in a weekend, they must work fast is all I can say..

Before you do anything this is the list of parts you will need, assuming you are using the later type four speed box with external gear change levers and overdrive (SE5a and SE6). Most of these parts are cheaper and easier to source from a donor car, there are still a few cheap bangers to be had but they are getting rarer every year.

You will have to pull the engine out to do this, see engine removal page HERE

Once the engine and gearbox were safely out and sitting on the garage floor, the gearbox, bell housing and torque converter were removed ready for the conversion to a manual gearbox. Essex engines that had automatic gearboxes fitted had a pressed in bush rather than a spigot bearing in the crank shaft, removing this cost hours of head scratching, knuckle skin loss and excessive swearing, my 60 something neighbor has learned so many new words since I started this project, sorry Betty! 

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Engine out, gearbox and bell housing removed, arrow in blown up photo shows location of freshly installed spigot bearing

The b*stard spigot bush removal tale.....

This job took the longest of them all and cost a couple of slide hammers as well as a large amount of knuckle skin and some sanity. I don't know how these things were fitted from the factory but it looks like the soft iron bush was drifted into the crank with a lumping great hammer. Getting it out was far from easy and I tried drilling and tapping into it before fitting bolts which were then attached to a slide hammer, all this did was rip the threads straight out with no discernable movement. I tried the old grease hydraulic trick to remove spigot bearings where you load up the cavity behind the bearing with grease and fit a sealed socket into the hole before hitting it with something heavy, this just shot a stream of liquid grease into my face. Finally I very carefully spent hours drilling through one side of the bush so that I could get at it with a drift and loosen it, the picture below shows the beating it took before it let go...

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I was grumbling about this to the bloke that skimmed the heads and he gave me a tip which I have subsequently used to free off other stuck parts, particularly bearings. All you do is quickly run a bead of weld around the inside of the part you are trying to remove, as the weld cools it contracts and shrinks the part by a small amount which is often just enough to free off whatever you are trying to remove. I haven't tried this with the spigot bush but if anyone has and it works please let me know.

Drilling holes for the clutch master cylinder and fitting a new pedal box

This turned out to be very easy, the pedal box has holes drilled into it to accept the master cylinders for the brakes and clutch, all I had to do was take a template from the pedal box, place it on the car and cut a hole. The template and locations can be seen in the photos below, I have a remote brake servo fitted to my car which made things a little bit tight on that side of the engine bay so I had to relocate it slightly further towards the nose.

template made from an old takeaway lid  holes drilled and engine bay painted

The pedal boxes for automatic and manual are the same size which means the bolt holes all line up nicely, its just a matter of taking the old one out and putting the new one in.

Contnued in part 2 HERE