Oil gallery plug

[DougR]

Hi folks,
I have a 1071 block and the oil gallery plugs seem to be non standard. There is a steel insert in the brass. I'm wondering if I drill the brass will it pull out or is it threaded? Also what will I replace it with? Any advice appreciated. Cheers, Doug.

20230621_234036.jpg

[Spider]

As it's non-standard it's anyone's guess what it it, though, having a slotted head like that, I'd say there's a reasonable chance it's threaded.

I'd pull the original brass plug from here and after cleaning, fit a new one.

[Exminiman]

That is a bit odd, it looks like the centre unscrews, but that would leave the brass outer, which is the last thing you want, if you are cleaning the oil gallery out.

With a bit if luck, if its not threaded, it will pull out with a slide hammer.

If it is threaded, then if you can work out the thread, you could just replace it with a whole threaded bung that is completely removable….

[diz]

It could well be an original plug that someone has previously removed with a slide hammer after drilling/tapping. The tapped hole has then been sealed off with the centre screw.
I had considered doing something similar myself as the original plugs seem far more substantial than the modern replacements.

[Peter Laidler]

That is the question. Is the brass plug threaded in or is it an interference fit? By being off-centre it looks like the steel screw is an added after thought to me. Just unscrew and replace.

But if it ain't broke, I wouldn't fix it

[mk1]

Could the original brass plug have been drilled through so they can rinse the oil gallery out and a plug put in afterwards to bung it up. i.e. the brass bit is the original plug.

Whatever way round it is, Personally I'd remove all that junk & tap the ends of the gallery to accept 1/2" grub screws. No point building a new engine with filthy old oil galleries.

M

[DougR]

Thanks for the replies. The off centre steel insert refuses to budge even with an impact screwdriver. The consensus seems to be that the brass is an original plug and that it should pull out so I'll give it a go.

[BAD942B]

go to a machine shop & mill one end out until its very thin & collapses, using a solid steel bar in the oil gallery drive the remaining plug out.
I put screw in taper plugs in my block 42 years ago

[Spider]

Thanks for the replies. The off centre steel insert refuses to budge even with an impact screwdriver. The consensus seems to be that the brass is an original plug and that it should pull out so I'll give it a go.

One way to remove it is if the plug on the other end can be removed, take that out, then drop a 400 mm length of 8 mm steel rod in through that end and tap this funny plug out. That's how I routinely remove the plugs. I would suggest avoiding drilling or machining this plug directly.

[DougR]

Thanks guys. I managed to get an m4 tap into the brass area and it came out. I drove out the other end with a long rod. Thankfully they weren't threaded. You were right. Someone inserted steel plugs into the brass plugs. Strange. No damage to the block so a good result and the gallery looks really clean

20230622_222141.jpg

20230622_222223.jpg

. Thanks again.

[mk1]

Great result.

[Peter Laidler]

GOOD job. A man after my own heart! Will you make new interference fit brass plugs? .0005" oversize. Leave to contract in the freezer overnight and they'll pretty well drop in - and expand - never to come out!

[mk1]

Much easier & better for the future to use 1/2" UNF grub screws.

https://www.ebay.co.uk/itm/293304331384 ... BMmKGM_Jxi

[Exminiman]

Or you could get a bit more anal and use a 3\8 NPTF or NPT type threaded plug

[DougR]

Thanks for all the suggestions. Very informative. I'm reluctant to tap the hole as the block is a bit precious. I like the frozen brass plug idea. I found a piece of brass rod but unfortunately it's 1/2 inch. I'll try to find a supplier of 13mm and turn it down. I get the feeling that nobody is a fan of these things although I used them in my 1275 S block and the oil pressure is great. Cheers, Doug.

20230623_193703.jpg

[DougR]

Can you offer suggestions as to the supplier of the best main bearing studs and nuts? Are the Minispares offerings not up to scratch? Is ARP the one to go with for absolute assurance? Thanks, Doug.

[DougR]

@Minisprinter thanks for that.
Cheers, Doug.

[Hipwell]

Thanks for all the suggestions. Very informative. I'm reluctant to tap the hole as the block is a bit precious. I like the frozen brass plug idea. I found a piece of brass rod but unfortunately it's 1/2 inch. I'll try to find a supplier of 13mm and turn it down. I get the feeling that nobody is a fan of these things although I used them in my 1275 S block and the oil pressure is great. Cheers, Doug.20230623_193703.jpg

Like most things the original rover ones were probably great, these days not so much.

I have used steel type core plugs and 100% reliable…

EBay item… 201201554638

[Hipwell]

Much easier & better for the future to use 1/2" UNF grub screws.

https://www.ebay.co.uk/itm/293304331384 ... BMmKGM_Jxi

Are you sure the size is 1/2” UNF? The holes are 1/2” drill size? I have seen people use 1/4” NPT, M14x1.5 and 3/8” BSP if you like drilling.

[251 ENG]

We use 5/8 unf hex grub screws that are 1/2" long in the main oil gallery . This does require the end of the hole to be drilled out .
The two smaller ones are drilled and tapped 3/8 unf for 3/8" long hex grub screws