Thread: 51 MG restoration.

And so it begins!
The tear down and rebuild of this late 90’s W58, 5 spd into a unit that will fit on Noddy’s Triumph engine.

Figure I’ll tackle this first as if it goes awry, I can pivot my plan to a replacement clutch for the existing 4 spd.

Slight end play in the input shaft bearing, but i don’t have the experience to know if it’s in the permissible range.
Pulled it apart and the good news is the gears all look very nice.No end bursts or grinding of anything noted. Synchronizer rings all turn smooth and grab well.



Slight bit of mung in the case, but nothing scary there either so figure I’ll order the one bearing, and new seals and gaskets. Call this good, button it back up and move on to pulling the power train on the car before it gets truly cold out.
Cheers gents.

One thing I never undersood or rebuilt.

I have always bought a used one.

Originally Posted by 32t

One thing I never undersood or rebuilt.

I have always bought a used one.

Yep. Soooo above my pay grade.

Love the mathematical, and technical beauty of these things.
Both shaft sets spinning together, synchronized such that as you shift that lever in the car it engages two sets of these gears. All those different ratios of teeth equaling the different speed ranges the car needs.
I know I’m a geek and Metalhead at the core, but just love how the input turns at one speed, and the output, because of the interconnection of all this metal magic a predictable different speed.

As far as this one in particular, super happy its in such pristine condition as looking at the edges of the gears attests. Would have always worried as I drive the car spiritedly if the tranny was gonna hold. Celica’s were hard driven sleds in some cases..

Might end up buying the standard full rebuild kit as the bearing by itself seems hard to find.
Will check with my auto guy tomorrow for specific items before I settle for amazon.
Cheers gents.

In my younger days...I’ve put in pistons,cranks,cams,lifters,heads...but nevah messed with 4 speed trannys or let alone an automatic. Also never set up a ring and pinion .

Every input shaft I have wiggled has a slight wiggle.
I would be tempted to button that puppy up and go with it, esp if the input shaft gear looks fine.
Those will handle a ton of torque. Seems you have found a good one.

Just me..

Thanks Tom. Was hoping you would chime in. Your experience eclipses mine when it comes to cars and your opinion bolsters my confidence.
Ordered the seals and gaskets from TMMC direct so everything will be like for like.
Will leave this wrapped up till after Christmas and start to strip the front of the car next..
Expect I can get her pulled apart before Christmas still, then spend the off season stripping the engine down and sending the head out.

Prudent decision I hope/think!
I expect that the biggest hurdle will be adapting it to the car.
Once you have that down pat you will likely be done. If future trans problems happen, you will have the zipper.

Originally Posted by nessmuck

In my younger days...I’ve put in pistons,cranks,cams,lifters,heads...but nevah messed with 4 speed trannys or let alone an automatic. Also never set up a ring and pinion .

I have welded up a couple of ring and pinions. You don't want to weld them tight but fill them in so they don't turn.

They all survived with a 4 cylinder engine driving them....