head bungs

[dgym]

hi i wonder if anyone has a picture of a head minus the coolant bungs between exhaust ports ? im going to have to drill them out and it looks as though there is a step inward that I dont want to run into.
cheers!
Jim

[types26/36]

Not sure if you are talking about Mk1 or Mk2 heads but here are some pics of a Mk1 head which have the core plugs (welsh plugs)
The later heads have a brass insert screwed in if I remember correctly.
No need to drill them out (if its a Mk1) bash a pointed screwdriver or such into the centre and lever them out.

[dgym]

thanks Brian
yeah I have a mk2 big valve head that has (had) threaded inserts that refuse to move. i've already made a hole through the centre and am wishing I hadn't touched them!

[rgh0]

If you have rounded out the socket and drilled a hole then 2 options that I would consider

1. A suitable large enough ezyout and more heat and chill cycles
2. Keep drilling in increasingly larger drills until you reach the threads in the plug and can collapse it......without damaging the threads in the head you really need to use a drill press and ensure you dont go in to deep to drill into the head inside the plug. An option is to use ( very carefully) a carbide cutter on a dremel at the last stage


cheers
Rohan

[Craven]

From a new QED head supposed to be same as original, looks like part of casting blocking hole.
May help.

[dgym]

thanks gents.
I might visit a buddy who has a bench drill and do gradually widening shallow steps. cheers!