Stripping the LLS gearcase - to match to an SJP waterpump housing.

The sjp forty plus uses the same lower gearcase as the LLS Century - I still need to get the top housing and an exhaust tube.

I have found an easy to order allumium stockest - and they sell 2.4m lengths of 2 1/4" tube at a wall thickness of 10 swg.

10 swg is 3.25mm - so it works out as an ID which is 0.15mm tight on the diameter for the 2" exhaust casting - so that should easily ream out a tad.

Link |The Aluminium Shop | its about £30 - but that would give you 6 short shaft tubes. Most of the alloy 40 series tubes are shot and hard to come by - and the chromed steel ones knackered - and the chromed brass ones 'hoarded' !

This gearcase was a mess. Someone had welded the prop spring to the end of the shaft, as the lug was broken - then I think it hit something, as the prop shaft was bent. Had to chop the end off the prop shaft to release the shaft.

Removing the Pinion bearing.

The pinion gear and the bearing were very bad. I had a spare, not new though. It came out reasonably easily. I bolted the housing down onto a board with its set screws - then rigged up the blowlamp to play on the side, while I tapped ( whacked) down on the pinion with a soft metal drift.

The spare is not too bad - as is the pinion. Trouble is - a new bearing is £32 - about the same for the pinion gear. Its the same diam as the prop bushes - so you can sort of check which is worn the most - if you have a good bronze prop shaft and bush. I shall see - if I don't need too much in bits for the entire engine I may go with a new pinion. The crownwheel is good - so it would be a bonus to have the new pinion gear.

Removing the prop bush

Heat the case up with torch for bit and tap down with some 6mm stud with a nut on the end - just the right size ! Tap it back in with a suitable socket on the flat flange. I had a couple of spares of these - but may fit a new one as they are only a tenner.

Changing the propshaft

Kindly, my new found boxes of bit came up with a good propshaft - with a very knackered crownwheel - ideal. The old crownwheel came off the bent prop with difficulty. The steel pin, peaned over either side, proved mighty tight. Even drilled down either end it would not punch out.

Ended up drilling it out - the pin is quite softish, and the gear super hard, so not too much of a problem. It appers to be 3/16th, as is the pin on the prop retaining collar, which is brass. Model shops sell 3/16th brass rod real cheap. This hole in the crownwheel seems ever so slightly less than 3/16th - somehow. Anyway, I had some suitable steel rod I made to fit snug for a new pin.

Same problem getting the old gear off - but I could grind into that one on the pin collar.

Pic

So - we have a stripped gearcase - all ready for painting up. The stud bar I used for knocking out the prop bush. The old bent propshaft removed from the crownwheel. The replacement shaft with its old gear.( missing a couple of teeth and babdly corroded ) The old pinion gear in the spare pinion bush.

Hopefully the casing is ok - it takes some welly to bend a shaft like that. I also have a brand new endcap from my many boxes of goodies !

Will have to think further on the pinion gear.