Arona 2 cylinder in Hartley Queenslander

[Bu Jim]

Greetings Skipper Pete I have returned from 5 days on the boat in Hobson Bay and very nice it was too. I will try and send some photos through for you to take a look at and offer your thoughts. The bottom sprocket slides up and down the shaft as the key way extends from the thrust bearing right through to the furthest forward movement possible of the sprocket.
What make of gearbox is that?
I am starting to think that the propellor is somehow fouled and will be going over the side to have a look once I get my crewmate onboard.
As ever thanks for your time and insights.

[skipperpete]

That prop shaft is a long way down in the hull Bu Jim, first there’s the drop at the reduction gear and then the second longer drop with the chain, I’d guess it’s hard to adjust the shaft seal so far down in the keel…. I’m happy to report that I’m not old enough to identify that gearbox but it looks like it might be an early relative of the old Lister gearbox, helluva heavy load on the shift lever to get it in and out of gear. Buy a spray can of chain lube to keep that triplex happy and quiet. Did you happen to take a look at the lower sprocket for a couple of set screws to stop it from moving, there’s a chance it could give you trouble in astern if it remains loose.

[Bu Jim]

Good morning Skipper Pete I hope all is well. The lower sprocket doesn't have any set screws I rotated it as far as I could and felt for them but nothing like I said it slides up and down the shaft freely. The key extends past the sprocket collar both fore and aft and when going astern I assume that the sprocket is hard up against the thrust bearing as is the the key. I had a go at splitting the chain and removing it so as to remove the lower sprocket I may have made unnecessary work for myself there as I was unable to remove the link. I will try and replace the link and split pin see attached photo. I have no idea why the photos rotate when I upload them so sorry about that. And yes it does require quite a deal of force to engage gears and when the exhaust pipe fell off the manifold it shattered the fitting that held the apparatus for moving the gear lever.
So there is a bit to do.
I will send photos through once they have arrived from my phone to my inbox.
Once again thanks for your time and help.
Cheerio for now
Jim

[skipperpete]

Hi Jim, I guess that makes the sprocket self aligning as it moves on the shaft, not an ideal situation but if it becomes a problem you can buy a Fenner taperlock hub and sprocket from any bearing supplies or industrial power transmission shops and lock it to the shaft. I’m pretty sure that there’s no way to eliminate your current arrangement so you’ll just have to maintain it as well as possible and in particular, that thrust block. In fact, it might be a good idea to get a shaft anode ( the one with vertical sides not the streamline one) and clamp it to the shaft ..say ¼” ahead of the stern gland as a way to keep it where it’s supposed to be. It’s worth threading a line through each side of the triplex chain so you don’t lose it into the bilge if you pop out the joining link, that’s not the most comfortable place to work.
Grease, lots of grease to keep that chain happy and quiet (ish)

[Bu Jim]

I managed to find the split spring link after the photo was taken.

[skipperpete]

G’day Jim, the spring clip only spans 2 pins , in your pic the link should be permanently attached to the left side pin of the three. It’s just like a bicycle chain , only bigger links ….but the triplex bit makes it more complicated. It might be easier to take off the chain completely and do a link by link inspection, worst case is you buy a new chain…. Best case you remove a link and add a joining link ( or re stake the pin on the loose link)