The Stovebolt Site Forums The Shop Area Driveline Opening my SM420 - Who knew it would suck!?!

The last time I felt the shock I felt tonight was when I took about a clock my dad owned when I was 10 years old. While my dad was out, I grabbed a screwdriver and opened up the back of the clock and springs and gears flew everywhere!!

That was the scene tonight when I decided I would clean up and start changing the gaskets on my 4 speed transmission. The first thing I did was pull the input shaft... then I heard a noise I dont care to hear again for a long time... the sprinkling and falling of 20 bearings into the gears inside the transmission. *sigh*

I pulled out magnetic probe and started to dig for the next 2 hours...

Worse was my discovery of what I thought was a broken gear...

<Gear>

But of course after reading the shop manual, I see that this is normal... *fewf*

Anything special I need to do to reinstall the bearings? I was planning on setting them in the clutch gear with some grease and setting the assembly back in.

Any other tricks to putting this back together?

Mark

You have it right. Its best to get some of the old long fiber grease. Pack the rollers in the shaft with the grease. Clean & inspect the brg. on the shaft. Shine a light in it & slowly turn it watching for any scores or pits. Replace the brg. if you find any. This is the first part to goon a manual trans. & will cause wining noise in the lower gears if its bad. The recess on the shaft is there so you can put in in & clear the counter gear.

Mark -
In addition to your Shop Manual, perhaps these links can help "unsuck" your SM420 ...

> 1949 Four-Speed Synchro-Mesh Transmission Overhaul Booklet

> Link to another manual - or possibly the same

Don't know if they will help. I know that I can't help you. The only thing that I ever did to my 420 was run it dry of gear oil. (Filled it up with Lucas 85w-140 and it survived!)

Good luck

Thanks guys!

Wrenchbender - thanks for the advice - the bearings look great, as do all the teeth on all gears.

Lonnie, thanks for the reference material, I've added it to my increasingly growing bookmark collection.