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Collection, Preservation and Display of Old Lawn Mowers

Certes Sloper Misfire

Was using an old mower to mow our bowls green and after about 40 mins of smooth running it started to splutter.

I'm assuming it's an ignition issue - coil or condenser. How do I determine which?

Should I fit a Meco ignition module? Where can I get one?

I was a bit gutted as I'd only just fitted a new breather from Meetens which was working perfectly.

Is there a decent guide to setting the points as I've mistakenly moved the timing.

Thanks - Dave


wristpin Fri, 11/09/2015

Simple things first!

Try a new spark plug making sure that its the correct reach and heat range. The existing plug may tell a story: coffee colour is good, black and sooty either a rich mixture or not a good enough spark to burn a correct mixture and white for a weak mixture. The plug connector is the next easy thing to check . If it has a suppressor they can break down. Try removing it and winding a paper clip around the plug terminal and sticking it into the end of the plug lead. If that cures it you have the answer.

Next check the contact breaker gap and and clean the points . That can be done without removing the flywheel but its easier with the flywheel removed. The flywheel is keyed to the crank so re-timing will not be required.

If the above hasn't solved the problem it's probably a question of getting the coil and condenser checked.

I like Meco units as once fitted its seldom necessary to delve into the magneto again but that said, a points system in good order is fine just so long as the machine is stored in the dry. When laying it up for the winter its a good idea to rotate the engine into the position where both valves are shut and the points closed.

This type of suppressed plug connector can be troublesome!