OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Walk Behind Lawn Mower Frames Question On Scott Bonnar Cylinder Mowers Model 45 - Engine Shaft Bearing

Hope I can get some advice. After fully rebuilding my 45 I have noticed a fair bit of noise when the engine clutch is engaged, ie when mowing. Hard to describe the noise but it sounds more like bearing than chain noise.
All chains and sprockets are in good nick and I replaced all bearings.
One thing that now has me concerned is a previous thread where it was mentioned that a self-aligning bearing must be used on the engine shaft.
I bought the model A1122225 bearing from TMS rather than the self-aligning A1122225/SA2 model as it was $10 versus $34. Could this bearing be a possible culprit?

Hi davo76, you have nailed it on the head...the engine shaft bearing must be a double row self-aligning bearing. There is a very good thread on this very subject. Click HERE. Please read grumpy's post # 36317. This explains the reasons very well.

Thanks Deejay,

So using the cheaper bearing would make noise? How come Rover went to the cheaper bearing if the self-aligning model is needed?

Rover went to a cheaper self-aligning bearing, not a deep-groove bearing.

Anyone have part numbers(Scott Bonnar or Bearing manufacturers) for the self aligning bearing?
Outdoor King couldn't get one in.

Hi Davo, I have replied to your PM...please check your messages.
For other members, the part number is A1122225/SA2; Engine Shaft Bearing; Double Row, Self Aligning as used in the original Scott Bonnar Model 45.

Thanks everyone for your help.
I have just installed a new engine shaft bearing and am amazed at the difference.
There is much less noise in general and from the bearing housing in particular. Another difference is a far smoother cutter engagement. Previously it engaged with a small bang, can only guess that the correct bearing alignment has helped reduce friction caused by a bearing that had side loads applied to it.
For anyone interested, the bearing is a 1202, double-row, self-aligning open-race bearing with dimensions: 15mm x 35mm x 11mm. I got it from a standard bearing shop for $26(had to ring around, was quoted up to $53 + GST!), more expensive than the $8 6202 deep-groove sealed bearing that it replaced but money well spent in my book.

Well done Davo. The deep groove bearing would only have lasted a very few hours anyway, using it misaligned, and it might have caused other damage.

I'll close this thread. If anyone needs to post to it, just send a PM to a moderator.