When I sent my cam cover's off for powder coating the guy behind the counter said he could not promise that he would be able to keep all the shot blasting out from underneath the breather plates. So since i got them back i have wanted to remove the plates and give them a good clean out, As the last thing i want is some shot blast media floating around near my cams when the engine all goes back together.
So here is my little walk through
Firstly I started with a hammer and a punch on the raised squashed riveted holding points. I used the punch just to help guide the first drill into place without it wandering.
I used a small 2.5mm drill to get things going.
I then stepped up to a 5mm drill to open out the holes.
Once I drilled them out i used another 5mm drill bit, using the blunt end I inserted it into the hole and gave it some leverage to crack off the remainder of the rivet.
Once all the rivets had been removed i could remover the plate, And my word there was som crud underneath.
So out came the bottle of Acetone and a tooth brush to clean all the parts up, Obviously keeping it well away from the painted side of my cam cover's.
Once the parts were cleaned and the gunk removed I set my mind on drilling and tapping some holes to accept my new stainless 4mm thread bolts. I used a 3.2mm drill and a set of three taps, first, second and final cut, all though just the final cut would be fine.
Once all the holed had been drilled and tapped, I proceeded to re-seal the plates and re-install them to the cam cover's.
I used some lock tight to hold the bolts in place as i dont want them coming undone.
I then ran up the bolts and cleaned up the excess sealant.
Bish bash bosh job done and i now know there is nothing inside them that may cause damage to my engine.
Gav