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MG MGA - Stiff Shift

Hey Folks, I got the 60 MG to my garage and it starts, runs (poorley) and drives! The first order of business is to change all of the fluids. Teh shifter handle is very diffacult to move and very "vague" Does anyone have any experience like that? Teh car sat for mor than five years. Tom
Thomas McNamara

Tom, there is a set screw at the bottom of the shift lever which attaches it to the shaft, via a spring. I think you have to take this out to remove the lever. Also a big C-spring on top of the lever ball joint.
Art Pearse

See here: http://mgaguru.com/mgtech/gearbox/gt203c.htm
Notice first five pictures at top of page, and read the text for description of the shift extension parts. If the hand lever moves around freely for a short distance in ALL directions, chances are the split bushing in the first picture is missing or broken (more common for a nylon replacement type part). If the lever moves freely full left to full right in neutral, then the remote control rod ie moving freely, and the hard motion problem will be farther forward. If the hand lever is hard to move in all directions, then the remote control rod may be dragging in the bearing journals.

You can remove the hand lever for inspection by removing a large snap ring below the rubber boot. This is probably not going to solve your problem unless all of the drag is in the spherical seat at bottom of the hand lever. If you pull the hand lever out the top you will most likely lose the anti-rattle detent ball out of the rear lever.

You can remove the remote shift housing assembly for inspection by pulling out the center carpet cover on the tunnel, removing 6 or 8 #10 screws around the perimeter, and removing the sheet metal tunnel cover. Then remove four 5/16" bolts and pull off the shift extension housing (shown in the pictures noted above). This will allow you to exercise the parts of the shift extension assembly independently, and maybe clean and lube the parts and get it working easier.

If that doesn't fix it, you can go after the rear lever on the selector rod with a big screwdriver or socket extension. If that part is very stiff you will have to remove engine and gearbox for further internal inspection.

Before removing the gearbox you might try draining the oil and filling it with automatic transmission fluid (thin and high detergent), or even mineral spirits, then drive it around some very gently to rinse out the inside and the working parts. If that works then drain an fill with engine oil, and maybe you save having to pull the engine.
Barney Gaylord

Hey Barney, thanks for the information, you are the guru for MGAs! Am I to understand that in order to remove the gearbox one must pull the motor? Is it also true that it can be done in situ, through the top? I'll know more this weekend. Regards, Tom
Thomas McNamara

Thomas,
Note that the gearbox oil is NOT hypoid 80/90 oil, it is engine oil, e.g., SAE 20-50, or similar. If someone has put in the heavy oil (like the diff oil) then the gear box may be heavy to operate.
Barney has it covered in his answer above, and yes the engine has to be removed, either with the gearbox attached (simplest way, I think), or first and then the gearbox follows.
It takes one day to remove and replace the engine with gearbox attached, once you've done it a few times!
Peter.
P. Tilbury

Hypoid 80/90 (a gear oil) is about the same viscosity as 30 wt. engine oil. They use a different reference. The mistake is when someone reads or hears that you can use 80/90 gear oil in a gearbox (I have seen it recommended in a book for Triumphs) and instead uses 80 or 90 wt engine oil. That is much heavier.

I wouldn't use hypoid for other reasons; high sulpher content could be hard on bronze or brass parts.
John DeWolf

This is interestng: http://www.bobistheoilguy.com/index.php?option=com_content&view=article&id=48&Itemid=55
James Johanski

Yes, the engine has to come out to remove the gearbox. The only part you can access in situ is the remote ahift extension (which has to be removed to get the box out of the car)

EP80W90 oil is not particularly thick, and will not in itself make for stiff shifting. It is about the same viscosity as 20W50 motor oil, just refers to a different viscosity index scale. The reason for not using EP oil in the gearbox is because the sulfur additives that give it the Extreme Pressure rating (for hypoid gears) tend to eat brass synchro rings.
Barney Gaylord

Tom,
One thing to remember, before you remove the tranny from the car be sure to drain the oil from it. If not it will drain out the tail shaft and make one heck of a mess on the floor of your garage.

Ray
Ray Ammeter

Just to close the loop, the cause of the "stiff shift" was a nearly frozen shift stalk. Some penitrating oil has freed it up nicely. It must have sat a long time. Regards, Tom
Thomas McNamara

This thread was discussed between 04/09/2009 and 11/09/2009

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