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SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sat Apr 24, 2010 5:39 am
by zemorph
when i pumped her up to full throttle there was a clunk and the prob stop turning.. im guessing its the shaft but i dont know a bloody thing about them, so i dont want to start unbolting it without knowing what im lookin for... can post pics or vid clips if anyone can help it would be very much appreciated! the engine still runs great tho....

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sat Apr 24, 2010 8:05 am
by zemorph
before i cleaned it.......

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sat Apr 24, 2010 8:32 am
by John1952
Have you checked the prop-spring, it holds the propeller on, has it broken?

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sat Apr 24, 2010 10:08 am
by zemorph
yes... its not the spring.... tried turning prop by hand and its stuck fast.......

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sat Apr 24, 2010 10:15 am
by skyetoyman
It is recommended that the prop is removed when running in a tank as yours is a direct drive ie no clutch. Turn the mag by hand to see if the prop turns
It is just removing a split pin and spring. John of SOS has new springs. The members of this forum are brilliant. from a rusty tank - no spark - leaking fuel and not having run for 10 years to a good 60's outboard that should run for another 40 - 50 years. All thanks to John of SOS and the forum.
Remove the gearbox (just two screws using a good screwdriver) and slide down to reveal the drive shaft. If that doesn't turn the problem is higher up. Again turning the mag by hand

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sun Apr 25, 2010 10:33 am
by zemorph
skyetoyman wrote:It is recommended that the prop is removed when running in a tank as yours is a direct drive ie no clutch. Turn the mag by hand to see if the prop turns
It is just removing a split pin and spring. John of SOS has new springs. The members of this forum are brilliant. from a rusty tank - no spark - leaking fuel and not having run for 10 years to a good 60's outboard that should run for another 40 - 50 years. All thanks to John of SOS and the forum.
Remove the gearbox (just two screws using a good screwdriver) and slide down to reveal the drive shaft. If that doesn't turn the problem is higher up. Again turning the mag by hand
thanks for that!!! the bottom end of the drive shaft has sheared off... any idea what length the drive shaft on a SJP 13379 is? how easy are they to get or could i weld a new piece on the end?

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sun Apr 25, 2010 1:30 pm
by woodbutchergraham
Welding could work, depends how proficient you are at it. Failing that contact John and get him to send you a replacement. Where in the world are you? There may be a member local with a spare, they may wish to help out you never know without asking .

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sun Apr 25, 2010 1:38 pm
by skyetoyman
While you are waiting for a nice forum member to send a drive shaft , I would be tempted to strip down the gearbox to see what caused the break . does the prop turn freely now
Unless it was very corroded in which case it would not be worth welding - it is not an item that usually fails

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sun Apr 25, 2010 3:03 pm
by zemorph
skyetoyman wrote:While you are waiting for a nice forum member to send a drive shaft , I would be tempted to strip down the gearbox to see what caused the break . does the prop turn freely now
Unless it was very corroded in which case it would not be worth welding - it is not an item that usually fails

im in New Zealand... stripped gear box and the problem seems to be too much movement, ie washers made of plastic?,.. shaft isnt too bad except for the bottom end.. was wondering if brass washers would be better or were the plastic ones supposed to be there?

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Sun Apr 25, 2010 8:03 pm
by woodbutchergraham
For a SJP the age is wrong for plastic or nylon washers, brass shims are the way to go. a slight notchey feel should be expected if set up correctly. Down under you have some real knowledgeable help and im sure with time someone will come to your rescue. Dependent on where in New Zealand you are?

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Mon Apr 26, 2010 11:18 pm
by zemorph
Im in Tauranga...... anyone out there know what the overall length of the driveshaft is for my SJP?

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Tue Apr 27, 2010 8:31 am
by skyetoyman
hopefully you still have the broken part of the drive shaft. Why not put the two pieces together and measure it ?

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Tue Apr 27, 2010 8:54 am
by zemorph
skyetoyman wrote:hopefully you still have the broken part of the drive shaft. Why not put the two pieces together and measure it ?
thought of that, but the bits off the end are crumbled to buggery....

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Tue Apr 27, 2010 10:53 am
by 40TPI
Not a question that is easily solved by searching through back posts or main site FAQ.... so hope this helps:

Part number P40/1353A std shaft length 20.75 inches. If you are able to rob a spares donor motor it is the same part fitted to all other standard shaft, direct drive models thus:- Forty Plus, Century , Silver Century.

Peter

Re: SJP 40 plus, got it going but CLUNK.. prop stopped turning

Posted: Wed Apr 28, 2010 8:42 pm
by woodbutchergraham
Dare i sugest, if its not broken to far up. Cut it square, trim the drive shaft to the same lenth, and the exhaust?
I guess i will be out cast for sugesting such a destructive fix. But if you can live with your Seagull shorter in stature its worth it.