cryogenics or freezing stuff

well that there is the best analogy i've ever had.

i was gonna say remind the boys and girls to put it in a sealed bag, rusty new crank and mains arent fun.

 

I have seen more than my share of rusty cranks! (jetski mechanic)

The rust pits the case hardening, then the rolling elements (balls or needles) start to peel the hardening, then the rolling elements start to run on the softer core steel, then BIG BAGA BOOM!

I love pulling down engines that have been sitting with salt water for months.

Pull out reeds, blow rod in half with gas axe (oxy), remove top end and press out piston with 50 ton press.

Hey Minor, Wax and I installed our first scooter crank yesterday!

Heated big side with mapp gas bottle, not too hot because of jb weld flow job, slight smear of oil on bearing land, slid crank in by hand.


Same method used to resleeve alloy cylinders with iron liners. Sleeves in freezer, cylinder in oven set to 250deg C. Drop sleeves in. You have about 5 secs to align ports using podger in ex port. Once cooled down enough to touch, put about 5 tons on top of sleeve in the press. This will properly seat the flange.

The best old English and yank lathes and mills etc. used to be left in a paddock for about 10 yrs to normalise the molecular structure before machining.

Let cool down and put on threebond 1211 sealant, heated little side and slid on by hand. Torqued bolts. Turns over nice and the needle barely moves on the dial indicator on either end. No hammers involved.

unk:

 

They are harder than jetski and outboard crank fitting.

Those cases split in line with the centreline of the crank. you just lay the crank in the top half, then bolt the bottom half down.

 

Like that (350 ypvs)

 

Looks swampy.