I have a 1952 A10 plunger. The gearbox leaked oil between the inner case and the main case. Soon found what I thought was the problem. It was assembled without a gasket. So purchased a new gasket and duly fitted as such. Also fitted a new bearing and bush during the rebuild. All went well until I tried to select the gears and there were only two. Checked the assembly process, the bearing and the bush but they seemed okay. After a day trying to sort it I removed the gasket and now I have four gears. Then reassembled it with the gasket to verify the fault. Again only two gears. It is as if the claw does not reach the cam plate.
I now suspect that some parts are worn and the extra distance added for the gasket is causing the problem. Rather than buying (if I can get them) a ton of bits what do you think is likely to be the worn parts and any thoughts on how to proceed?
Are you sure you have got the indexing between selector and cam plate correct. This is the usual cause of loss of gears on reassembly.
Other possibility is the gasket - the original would have been a thin paper item - some replacement items are thicker modern material.
Thanks JulianS. I am comfortable with the indexing. That was a bit of learning curve.
The gasket is about a 1/16 of an inch. I have Gascoid paper that is about 7 thou. Do you think that was the type of gasket fitted originally?
Yes thin paper - BSA started using the thicker material in the late 1960s.
Usually the cause of failing to select, almost like grasping air when trying to engage, is due to the indexing. I presume you are rotating the gearshafts when trying for the gears.
Thanks JulianS. Put it back together this evening using the thin gasket and it works fine.
Thanks very much for your help.
Jack