Cut out and will not start.

[Dohnut]

HOORAY.....She's running.
THANKS for all your help guys, I've certainly learnt allot more about Seagulls thanks to this site. By the way Chris I do carry spares on the water and I give it a "once over" everytime before I take it out on the River.
The Problem was fuel intake, (lack of suction) Both nuts connecting drive shaft, had come loose on return trip! I got about one turn on one, and THREE on the other (very difficult to get spanner on).
I must admit I did not notice these were loose (Obviously) and would not have realised they could cause such a problem. I KNOW NOW !!!
I now have a running engine with several new parts and loads of EXTRA spares!!!
Thanks again ALL.
Tony.

[Clifford Pope]

I've just logged in to post exactly the same question as here, and find someone with identical problems.

Mine's a 40 plus too, and was running well until it suddenly cut out. I have checked all the items already listed, and replaced the plug.
There is a spark, and the plug gets wet with fuel, but won't fire. I have tried whirring it on an electric drill, at different settings of choke and throttle. I have tipped all the fuel away and made up fresh, cleaned and checked the contact points, but nothing has made any difference.
I have managed to get one brief cough from it.

Is it likely that the magneto or condenser can partly fail, and produce a small but insufficient spark? Can these be checked, or is replacement the only way forward?

Thanks anyone.

[Waggles]

It most definitely is possible to have a weak spark that 'dies' when under compression in the motor.

Have you replaced the HT lead? and make sure the points are really clean and making a good contact when closed and open to correct gap. Another thought, is the magneto back plate in the correct position and tight? if it is loose and moves then the timing will be wrong.

Am sure someone more knowledgeable could give you some figures to test the magneto, am afraid my testing only goes as far as putting an Ohm meter across the points to ensure good contact then checking for 'big fat blue spark' at the plug, appreciate thats a bit subjective though.

I assume the motor died while running same as the other?