Ariel Owners Motorcycle Club

Hello Paul - or anybody else who can find the item concerned.

I think you had a Square Four ignition problem which you traced to a bad contact or broken wire in the distributor, but I cannot find the item concerned despite searching using all the relevant terms I can dredge up.

There's a guy in Australia who is experiencing intermittent cutting out, and I thought it worth trying to track down what I may be mis-remembering anyway. It's a Mk11 he has.

Thanks for any help on this, Roger

This is a tricky one Roger. In my experience, it doesn't really matter what the problem is with a Square Four but the symptom is invariably misfiring. I think the post you are looking for recounted the misfiring problem I had on my first Healey when the strap which runs round inside the distributor to the terminal on the side became unsoldered from the screw terminal. The bike ran fine until it got nicely warm when the misfire set in. Resoldering the terminal into the strap solved the problem.
Other options I can think of include deterioration of the rotor arm (although this usually means the engine stops and will not go again), the contact breaker tungsten end falling off one of the points, a duff coil, HT lead/leads shorting out, especially in damp conditions, electronic ignition failure, poor earth between engine and frame and loose connections. Then you can start on the potential carb problems.
If this doesn't help your man in Australia, give him my direct email and tell him to describe the symptoms in detail to me.

Thanks very much, Paul. That first one is the one I was thinking of.

I'll pass on your very kind offer.

Happy etceteras, Roger

Hi Paul, I'm the guy with the problem. I have your email and will reach out if my trouble-shooting fails to yield a result. I will pack a tool roll and circuit tester next time I head so, if she conks out, I will have some diagnostic options available.

As a first step, make sure the vent hole in the petrol filler cap is clear. The best way to do this involves dismantling the cap then putting a small drill (1/16" from memory) down the hole in the tightening screw and making sure you can see the drill from the hole in the side of the screw. I have known an AOMCC Chairman have trouble with this fault after polishing his bike and getting wax in the hole!