Oil Galley Plug Thread size

[sam93]

Can anyone please advise me on drilling and tapping the hole which has the hammered in aluminium sealing plug on the 6cyl block? See photo.

I want to convert to using a remotely located oil filter. On this note has anyone got a drawing of the blanking plate which will need to be manufactured? If not no problem, I'll figure it out from one of the spin-on filter adapters.

Thanks all,
Sam.

[RobPearce]

I wouldn't mess with that plug for a remote filter. I know the factory oil cooler kit did but that requires a special (and very rare) modified filter housing. The usual remote filter conversion just replaces the existing filter housing.

That said, I had to re-tap that hole on Tessa because the block had been acid cleaned and the aluminium plug dissolved. The replacement plug wouldn't screw in until I'd re-cut the thread in the block. I think it's a BSPT thread (unlike the ends of the main oil galleries which are 1/4 NPT)

[Nick Jones]

It's 3/4" UNF.  Mine has a piece of cut down bolt in it, loctited in, and is itself drilled and tapped 1/8" BSP to provide an additional, external feed to the front of the oil gallery.

Nick

[sam93]

Thanks for the info. I was thinking of something similar to your setup nick to try and reduce the bottle neck area of the oil galley.

It's all come about as I've been rebuiling the engine (hence the yellow paint). I hit a problem with the small plugs. Couldn't install the new ones, as in my error I cleaned them up with a UNF tap. I'm going to have to oversize the rear most one as the thread has now broken away after trying a load test.

Trouble being that I've only recently rebuilt the bottom end, so I'm looking at other improvements that can be carried out to the oil galley whilst I've got it apart again. There's some great info on the "new engine"  thread that I found.