Gear not changing fron 2nd to 3rd

[raahul2008]

Hi guys,
I have 1994 1.3 efi automatic mini.
When i start the car in the morning and put the gear selector on "D" and drive everything goes fine and the gear shifts properly. After a while when the engine is heated up while on "D" the gear automatically changes from 1st to 2nd but it is not changing from 2nd to 3rd instead it just revs high. At that point if I manually move the shifter from "D" to "3" the gear changes from 2nd to 3rd. But then no way to reach the final gear. I wanna know why the auto shifting is not working when I am on "D".

Thanks in advance for your help.

[Stu]

Hi,

Not posted here for a while, but good to be back.

Hmm. Well manual shifting moves the selector shaft in the gearbox and changes the valve block oilways to engage / disengage selected gears on the geartrain.

Auto selection is controlled by the governor, a sprung spinning arrangement with flyweights which move a lever on the valve block to engage / disengage the same gears.

It could be a few things, but most likely something simple.

Do you know what grade of oil is in the engine?

When was it last changed?

Have you checked the oil level?

Have you checked the gear cable tension / operation?

[notamini]

There have been posts in the past where someone has placed the governor bits in wrong. Apparently quite easy to do. Think it was kick down leaver backwards inside case?

[Stu]

Yeah. That's why I've taken lots of photos for when I eventually re-build mine

To the OP, I think you'd be best to go through the easy things first, and start with an oil change (use the correct grade and check level correctly) and see if it improves.

A more serious cause may be sticking valves in the valve block. If the engine oil isn't changed regularly, sludge can build up and cause operational issues. Removal of the valve block can be done with the engine in, but might be a little overwhelming depending on your mechanical experience. 

I assume the engine and gearbox has not had any 'fettling' recently. Have you owned the car long?

[jockduck]

I had a problem with the governor not sliding up and down its shaft due to rust! box would not change automatically but fine in manual, an engine out job I'm afraid, fixed it using a big screwdriver through the governor 2 bolt hole at the back(kickdown rod)of the box exercising the the governor back and forward until it was free.
Jock

[Stu]

I'll have to remember that one Jock. It's surprising it'd rust up considering there's oil in there. Had it been sat for a time?

[jockduck]

Hi Stu, No it had not sat for long, I rebuilt it and the car was not ready for a couple of months but it was in Darwin where the humidity gets into everything especially in the Monsoon season. Still going fine after 15? years.
Jock

[mra-minis]

Dec 9, 2016 22:53:12 GMT jockduck said:

.... Still going fine after 157 years.
Jock