Saving Old Seagulls

One nice afternoon my 40+ started to behave as if it had a clutch. The motor was running, but not the prop.

As shown in the pictures the axle going down in the gearbox has become round, I suppose it should be square. Right?

It seems as if I need to change the lower end of the drive shaft or maybe the whole drive shaft. And the axle going down to the pinion driving the prop shaft. I know the my father had a similar problem with this motor about 30 years ago. I wonder if the whole drive shaft or if only the lower end was replaced at that time. How do I get the axle going down in the gearbox out of the lower unit? Do I have to remove the prop shaft, then remove the pinion on the axle and then pull the axle upwards from the gearbox. Or should the axle go down into the gearbox?
How do I remove the prop shaft? I assume that I have to remove the bronze retaining ring between the gearbox and the prop and then push the shaft into the gearbox?

Any info on how to reconnect the drive shaft and the pinion will be very much appreciated!

Henrik

By the looks of things you motor may once have been a short shaft, you may be better off getting a donor bottom end rather than knocking the pinion gear out.
You would have to replace the pinion and drive as you may end up with the same problem.
Remove bronze retaining ring, by removing pin and pinion goes up and out.

Before you do that, remove the gearbox endcap top retaining screw which is the locating screw for the pinion sleeve bearing.
You also have to fully strip the gearbox first & drive the pinion & sleeve out, with an ally drift & it might need heat.

The drive shaft should be in one piece.

Does your gearbox still turn freely? There must be a reason for the pinion shaft being rounded, perhaps a gearbox seizure?

For a guide to the gearbox internals have a look at this:- http://www.saving-old-seagulls.co.uk/im ... 000028.jpg

Thanks all! That is a lot of good info.

I will have to strip the gearbox and then I will contact John for the price of the spare parts.

The motor has always been a long shaft - my father bought it new in '62 (I still have the bill of sale) and it has been in the family all the time. The number SJP39669L also indicates a long shaft. But as I mentioned above the drive shaft might have been repaired in this way due to shortage of proper spare parts. Or Pa being economical (read stingy).

But there has been no sign of the gearbox being seized. I suspect the square-turned-round axle is simply old-fashioned wear.

Best regards,

Henrik

Corosion will do that to the drive. What surised me is i have a 40+ crank ruined due to the square almost rounded.