What is the size?

[steplift20]

Thanks spare, but honestly I have no idea what you mean.
But can I pull out the coil,attach the spark plug and turn over the engine and see if it's got a spark? I would stand by the plug while my son cranks the engine
What do you think?
I just what to make sure he is getting spark to all the cylinders, but I have a feeling the compression test is not going to have a good out come.