What should be a simple job is proving difficult. Tried to remove the plug preparatory to doing the vales and could not get the plug spanner to engage. The picture shows why, there is some sort of rubber bung sitting on top of the plug but so far no amount of digging around with hooked wire and suchlike has shifted it. It seems to be jammed very tightly and my knuckles are raw trying to dislodge it. My guess is that the rubber is from the inside of an original MZ or Yamaha plug spanner which has become detached and then pushed down by the plug cap but why it should be so tight is a mystery.
Anyone had this problem and if so how did you solve it, I am going to try grinding down an old kitchen knife to make a chisel to try and cut it into smaller chunks but you are working blind all the time and the confined space makes it hard to get any real pressure on the tool.
Makes me wonder how long my plug has been in place.
Peter