Drilling the brass oilway plugs out

[rolesyboy]

I have stripped my block to the bare bones and only have the brass plugs over the oil galleries to remove. Trouble is I have a nagging doubt that I might mess it up if I don't check how to remove them. I presume drill out the centre and keep going till its all gone but I would prefer to take advise in case I cock it up. Anybody? Cheers. Mark

[coop12g295]

I drilled mine and tapped them 5/16 unf I think and used a long bolt and big nuts with washers to slowly pull them out came from a Mini Mag article by Keith Calver last year.I'll try to find the mag and let you know which one

[Spider]

I drilled mine and tapped them 5/16 unf I think and used a long bolt and big nuts with washers to slowly pull them out

That's what I do too. Once I have the first one out, I drop a long 8 mm rod in where I removed the first one, right through the block and then knock the other one out.

I only remove the ones for the main gallery and the oil pressure relief valve. The ones for the Main Gallery are on either end of the block. When you look at the ends, you'll see 2 on each end, you can pull them all if you like. I don't bother with those on the tappet chest drain, only those towards the dissy side of the block.

For the ones for the pressure relief valve, they are much smaller. I generally use a roofing screw (these are more tensile than a self tapper) in the slide hammer. Same for the one in the cylinder head, unless it's a late one that has the pop-rivet. In that case, punch the centre in to dislodge the sealing stem, then drill the rivet head like any other rivet. Then I use the slide hammer again, but be careful not to expand the rivet any further. Also make sure you get the stem out!

When replacing them, I use 14 mm cup point grub screws for the main galleries. I use only a taper tap and thread it such that it leaves a tappered thread in the hole, but deep enough that the cup will seat on the register within the hole (you'll see that when you remove the plug. Be sure that they don't go too deep or you'll restrict the oil way to Main Bearings 1 & 3.

The ones for the oil relief valve, I use 5/16" UNF Grub Screws. Be extra careful that these don't go too deep or it will block off the relief valve passage within the block. You'll know you've done that when the oil filter explodes! No, don't ask me how I know Same size for the one in the head too. Again, with all these, a taper tap, leaving a tapered thread.

I think I have some pics I can put up a little later.

For sealing, I just use a thread locking grade of Loctite, but only a low strength one.

I am not a fan of replacing the plugs with the same again.

[rolesyboy]

G'day Spider - I really would like to thank you personally for all of your help. Let me know your address and I will be over. Just say the word

[Vegard]

I drill and tap mine 12mm and leave them in there. Why remove them altogether??

[Spider]

Rolesyboy, you're welcome there buddy. You can drop in anytime, but be prepared to be put right to work

Some pics I have on file (them may seem a little odd, as they were taken for another purpose)



This one shows the Main Gallery Plug and the non-pressure plug of the Tappet Chest. I don't really see the point in pulling the non-pressure plug.




This is the other end of the Main Gallery.




These are the ones for the Oil Relief Valve Vent. You really need to be vary careful how deep these end up.