Just Engines Ignition Systems Info

Can I use this system on any engine?
More or less, yes. It is not designed for engines designed to transport people.
Is it a difficult job?
It does involve some basic engineering skill. The magnet needs to be mounted in the prop-driver and the hall-effect sensor needs to be mounted on to the crankcase.
What will I need to complete the conversion?
You will need a single ignition, the 120 degrees cap one is designed to be a better fit on the more recessed plugs on four strokes, the standard 90 degree cap is suitable for all other engines. You will need a spark plug, and a magnet. You can see and order these items here.
Do I need to adjust the compression?
Yes you will need to either lower the compression of your engine slightly or retard the ignition slightly. Lowering the compression is by the addition of head shims - generally available as spares for the engine - we sell shims for all our ASP (also fit SC/Magnum) and our JEN engines here.
Can I use Glow fuel with spark ignition?
Yes you can. You will need to adjust the timing or compression accordingly.
Can I fit your ignition system as a replacement to my petrol engine?
As a rule yes. Our unit works with one magnet in the drive hub. If your engine has two magnets one would need to be removed first. You will need to measure the AF (across flats) measurement of your spark plug as the units are sold to fit specific plug sizes. (The plug caps are designed to fit tightly over the plug.)
Do I need to change the carburettor?
No, most of our customers find they can continue using the same carb. The adjustments are a bit finer for petrol but achievable. Walbro carbs are available for engines of 17cc 1.00CU upwards. Note they do need a pressure feed from the crankcase to operate the pump.
What Petrol Oil mix should I use?
We recommend 20 - 25 : 1. Use a good two stroke oil from your local garage or garden centre.
Will I lose power?
Yes you will lose a bit of power but you will gain fuel economy. Most modellers are happy with the trade.
What else will I need to do?
If you are converting an engine from glow fuel, you will need to change the fuel tubing and the bung from your tank.
Do I need a kill switch?
Petrol engines are designed to tick over with the carb fully closed. So it is a wise precaution to be able to stop the engine remotely.


Order Line: Tel: 01747 835817 - 8.30 to 12.30 and 1.00 to 4.00 Mon to Fri.

For further information, pricing, or if you just can't see what you need, please ring us as above or Email us at support@justengines.co.uk