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Re: My new engine a 125
Posted: Sun Jun 23, 2013 1:28 pm
by Stelios_Rjk
Is there or did you remove a spring from the propeller shaft?
Re: My new engine a 125
Posted: Sun Jun 23, 2013 1:50 pm
by kitepaulx2
no spring on the prop
in or out of gear the square shaft at the engine turns but the prop shaft does not turn
Re: My new engine a 125
Posted: Sun Jun 23, 2013 2:28 pm
by 1650bullet
I think what you are saying is the shaft that the prop slides over is not turning. Am i wright. Remove the prop and see if the shaft alone spins. Make sure you have got it in gear. Either forward or reverse.
Re: My new engine a 125
Posted: Sun Jun 23, 2013 2:59 pm
by kitepaulx2
nothing turns prop end
tried both positions with gear level
prop is off
Re: My new engine a 125
Posted: Sun Jun 23, 2013 5:42 pm
by Stelios_Rjk
Since the propeller shaft is not moving no matter where is the clutch fork you have to undo the screws and see what's going on inside. An explanation could be that it's missing the crown wheel thrust washer (S1383). Had happened that once.
With the gearbox cap screws.. Be gentle. To much torque applied could lead in seared or snapped screw. Apply head (a lot) if they don't get off.
About the prop, I don't know if this prop is correct for this gearbox. I think this prop needs a spring carrier and another type of spring, not the one used on silver centuries etc.
Re: My new engine a 125
Posted: Tue Jul 02, 2013 8:37 am
by kitepaulx2
My bent pin from the gearbox tis a little "z" shaped and the other pin has been drilled.
Any thoughts on where to get some new pins from, seen them in repair kit's £25 each and you get one, so £50 for the two I need.
Re: My new engine a 125
Posted: Wed Jul 03, 2013 10:53 am
by phil
Shear pins often look like that. If its mild steel you can probably straighten it, or make one from a common nail of the correct diameter cut to length. The price you quote seems way out of line. The key things are the material it's made of and the correct size.
Re: My new engine a 125
Posted: Mon Jul 08, 2013 10:04 am
by kitepaulx2
Got a foot of 3/16 silver steel of the fleabay for very little just awaiting rebuild now then all good to go.
Also wheres the best place to put a anode

Re: My new engine a 125
Posted: Mon Jul 08, 2013 10:43 am
by Stelios_Rjk
I don't think there is place to put such an anode. In addition with so much aluminum Seagulls may need anodes made from magnesium. Aluminum corrodes easier than zinc so zinc anodes may not work.
When I was thinking to use anodes I end up to the conclusion that the aluminum exhaust works as a big anode. It won't be bad of course if you mount an anode on the block. May save some corrosion.
This hypothesis is true when we are talking about pure metals and not alloys. Here things may be a little bit different. But using magnesium anodes should be safe and bring results according to the anodic index.
Re: My new engine a 125
Posted: Wed Jul 10, 2013 8:59 am
by kitepaulx2
does anybody have the fitting that goes on here? and want to get rid of it?
Also need chunky split pins just in case like... these are bigger than the standard pins that are used with the spring on other seagulls

Re: My new engine a 125
Posted: Fri Jul 12, 2013 8:19 am
by RickUK
I might be talking cobblers, (memory plays me up now), but I think that gearbox has a spring inside on the proshaft to keep the gears in engagement - seem to recall that I had one where the spring has rotted through due to lack of lube in the 'box, so the gear has wandered about and chewed the pinion up, but the result was no drive to the prop. Is this your problem?
The springs are avalable as spares.
Re: My new engine a 125
Posted: Fri Jul 12, 2013 8:53 am
by Stelios_Rjk
There is a spring inside the gearbox that pushes the clutch dog (which is on the prop shaft) onto the crown gear. Indeed if this spring is gone there is no drive. In addition there is no drive in case the thrust washer is missing.
Heat and the correct spanners.
Re: My new engine a 125
Posted: Fri Jul 12, 2013 10:05 am
by Charles uk
That spring & carrier is for a model 90 FNR gearbox,
the 125 has a cushion hub prop on a FN 2.5 : 1 sealed gearbox.
Re: My new engine a 125
Posted: Fri Jul 12, 2013 11:55 am
by Stelios_Rjk
OK, so I am removing the picture.
Re: My new engine a 125
Posted: Fri Jul 12, 2013 1:20 pm
by kitepaulx2
washers and shims have arrived from john, thank you
Just need to work out best washer, then ready for testing...