We have a reader who is in possession of an Innocenti Mini 850 from 1969 with automatic transmission. However, the owner is becoming less and less happy because the small thing clearly noticeably switches to the next gear, is absolutely lifeless and uses a lot of fuel.
He has had the opportunity to drive with a few other automatic Mini's - that alone is unique, because there aren't many of those cars to be found - and he got the same experience there. Then he drove other cars with an automatic transmission and they all switched 'smoothly', almost imperceptibly to the next corridor. He now has plans to replace the automatic gearbox with a manual transmission. Before he does that, he wants some 'advice'. That 'shocking' and clearly noticeable switching to a higher gear with a Mini Automatic is part of it. This is due to the construction of the gearbox. Get used to it at a given moment. Just like the 'bumps' of the rather 'stiff' trolley. With regard to the slow acceleration and the high fuel consumption, we would advise you to carry out a service. Check new spark plugs and contacts, new air filter, carburation and then adjust everything exactly according to factory specifications. If you are still busy, also change / replace the oil and oil filter and check whether the brakes might 'drag'?
Manual
Replacing the automatic gearbox for a manual transmission is a mega job. The engine of an automatic transmission has a different crankshaft ... and it will have to be replaced. In addition, a main clutch cylinder, auxiliary cylinder, shift rods, poker must be placed ... The shortest blow, to purchase a complete demolition Mini on a scrap yard with a still good running engine and good shifting gearbox and mount it in your Mini. With regard to that purchase, we would 'go' for at least one 998 cm3 power source. After that you will have to stop by the RDW to have the registration certificate changed ... All in all, quite a job. With fresh (engine) oil and a new oil filter, the cart will probably switch to the next corridor in a much more 'friendly' way. And otherwise there are two more options, either getting used to it (a classic cannot be compared to a modern car, even if that 15 is years old) or selling the car ...?
Converting an Innocenti Mini Automatic to manual transmission is a mega job, moreover, given the rarity, almost criminal…
I am curious about the difference between the crankshaft automatic transmission, manual transmission and the loin of the Morris Minor 1000?
I also had one and after 60.000 the gearboxes always got stuck.
Then they remained in 1 gear and shifted no more.
This was indeed because the oil from the engine was also the oil from the gearbox
and also switched the 'brains' of the tank to oil pressure.
When the car gets older and the gear tires start to wear out, this sharpening gets into the oil and also into the brain.
This collects and after a while the oil cylinders of the tire drive will clog and the car will remain in 1 gear.
My advice is to make a mixture with oil and diesel, just replace 1 on 1 and replace the oil in the car with it.
Then go for a quiet ride and let the diesel dissolve the sharps and float.
Drain the oil and check for sharpening.
Repeat this every year and check if it stays clean.
The machine and the engine form a whole and run on the same (engine) oil. Slightly thicker oil can help.