This is the first time I have worked on a commando engine and just needed to replace the gasket to stop a leak from the timing cover.
This engine has a Boyer ignition, and when I removed the cover screws I noticed the boyer plate behind pickups was stopping removal.
I removed the cap head screw from the plate and used very little force on the timing cover as did not want to break anything. The cover did not come off so decided to post here to get help from experienced Commando owners.
Ensure that you mark the position of all the parts of the ignition system in the cover to aid reassembly and don't turn the engine over until you've reassembled everything - this will save having to re-time the ignition. As you say - the Boyer rotor will prevent removal of the cover. Unscrew the rotor central bolt and withdraw it most of the way then tap it down and then up to 'shock' it loose - it is on a slight taper in the camshaft thus the tightness.
Thanks for your reply, I have taken the pickups of after marking position but I am still not sure about the brass plate holding the magnets.
The caphead screw retaining the plate looks to be 1/4 UNF but I noticed that the plate has a slightly larger diameter thread at the start that this 1/4 UNF bolt passes through.
Would I be correct in saying that you use a bolt on the larger thread and maybe a slide hammer to remove?. If so I have not been able to work out what diameter or thread it is.
... a short bit of rod dropped into the hole so that a bolt in the larger thread (5/16" UNF if memory serves - which it probably doesn't) will push against it and act as an extractor.
Thanks for the reply, I tried a 5/16 UNF but could have measured thread incorrectly so will have another look tomorrow night.
It would be advisable to have to hand the camshaft oil seal tool, part number 06-1359, as the seal can be damaged on re-installing the cover and leak oil into the points cover. Also fitting a new oil pump nipple seal is recommended when removing the cover.
Andy, the tread in the rotor is 5/16 unf . Just thread a bolt in a little way and wiggle it. It's only a short taper fit and comes out easily.