Jubilee mains bearings

Previously Dan Field wrote:

Don't do what was done on my bike, where the PO drilled two holes in the cases to drift them out! I'd use heat (put it in the oven) and a blind puller if necessary?

Very Many Thanks.

Roy.

Many thanks.

Roy.

Previously peter_holland1 wrote:

Previously roy_johnson wrote:

Does anyone have any "handy hints" for removing the mains bearings from my 1960 Jubilee?

Hi Roy,

May I suggest a method that worked for me.

Split the crankcase halves. That should leave you with the roller inner race on the crankshaft drive journal. The roller outer race stays in the drive side crankcase.

Gently, taking great care not to damage the oil feed taper on the crankshaft timing side, tap the crankshaft out of the timing side crankcase. This should leave the timing side main bearing in the crankcase.

Now remove all studs and dowels from the joint faces of the crankcase halves. Remove any oil seals. Clean the crankcase halves of oil and grease. Get a piece of plywood about 600mm or 2ft square. Bigger will do. Wait till wife has gone out and turn oven to full.

Put crankcase half, joint face down, into hot oven for about 15 minutes, ignoring smoke output. Be prepared for bearing to fall out of crankcase while in oven by putting a baking tray below to catch it.

Oven gloves on, plywood on floor in front of oven, grab hot crankcase and slam joint face down onto the plywood. Again if necessary. The bearing drops out. Same for both crankcase halves.

A special bearing puller, called a Mechanical Bearing Separator Clarke CH253, and sold by Machine Mart, is required for roller bearing removal on drive side crankshaft. Other makes will do.

I expect there will now be a string of responses telling how the whole job can be done with a garden spade, but this worked for me with absolutely no damage on a machine that had stood for 30 years.

Good luck

Peter

Previously peter_holland1 wrote:

Previously roy_johnson wrote:

Does anyone have any "handy hints" for removing the mains bearings from my 1960 Jubilee?

Hi Roy,

May I suggest a method that worked for me.

Split the crankcase halves. That should leave you with the roller inner race on the crankshaft drive journal. The roller outer race stays in the drive side crankcase.

Gently, taking great care not to damage the oil feed taper on the crankshaft timing side, tap the crankshaft out of the timing side crankcase. This should leave the timing side main bearing in the crankcase.

Now remove all studs and dowels from the joint faces of the crankcase halves. Remove any oil seals. Clean the crankcase halves of oil and grease. Get a piece of plywood about 600mm or 2ft square. Bigger will do. Wait till wife has gone out and turn oven to full.

Put crankcase half, joint face down, into hot oven for about 15 minutes, ignoring smoke output. Be prepared for bearing to fall out of crankcase while in oven by putting a baking tray below to catch it.

Oven gloves on, plywood on floor in front of oven, grab hot crankcase and slam joint face down onto the plywood. Again if necessary. The bearing drops out. Same for both crankcase halves.

A special bearing puller, called a Mechanical Bearing Separator Clarke CH253, and sold by Machine Mart, is required for roller bearing removal on drive side crankshaft. Other makes will do.

I expect there will now be a string of responses telling how the whole job can be done with a garden spade, but this worked for me with absolutely no damage on a machine that had stood for 30 years.

Good luck

Peter