11 replies to this topic

[Nick Warwick]

Can somebody tell me the correct way to install and "stake" the plugs please.

Any photos would be helpful too. I will be using some lock tight with the plugs too.

Thanks
Nick

[Cooperman]

The current oil gallery plugs are nowhere near as good as the old solid ones. With the cup-shaped ones I just push them in firmly and use Loctite Bearing Lock to secure them. Unless the holes for them are oversize due to drilling them out the new ones should fit quite snugly.

[Gr4h4m]

I tapped mine and used removable screw in bungs that I also sealed with bearing fit.

[Cooperman]

That is what needs to b done with competition engines which need to be stripped & re-built regularly. Not so necessary for a road engine, but never a bad idea.

[dklawson]

+1 more vote for tapping and fitting threaded plugs.

[Captain Mainwaring]

and another vote.

[Nick Warwick]

I did think about tapping the holes but i have the engine built up now.

 

I cant see a way of me tapping the holes and not getting swarf down the galley. I think for now i will just put them in and if i have to do another rebuild i will tap them.

 

As for staking is it just a case of a screw driver and hitting the edge that meets the block together?

 

How far into the block should they go? flush?

 

Thanks for the help

[Cooperman]

I always just clean the hole out so that it is clean and grease/oil free. Then I coat the plug with Loctite Bearing Seal and tap it in, finally tapping it fully in with a small socket of the right diameter. They can go in just slightly more than flush, maybe around a further 1/16".

[carbon]

Nick,

 

Is your engine build A or A+?

 

For A block there are two main oil gallery plugs, the one at the timing end cannot push out if you use the standard timing backplate as this partly covers the plug.

 

For the flywheel end I had a plug blow out, due to fitting ball bearing in the oil relief valve, but that's another story... So I had to refit this, but like you I did not want to tap the gallery due to probems with swarf on a built motor.

 

What I did here was to drill and tap a 2BA hole just adjacent to the gallery bung, and used a large thick 2BA washer under the 2BA bolt, so the washer covered part of the plug. It's now been in place for best part of 20 years.

[Projectmini_kwt]

I dont know if this post is still going but can you tap them in too far??

Edited by Projectmini_kwt, 01 January 2019 - 02:22 PM.

[Spider]

If using either type of Factory Plug (the older solid types or the later Cup ones) on the Main Oil Gallery - No - unless the Main Oil Gallery has been drilled out.

 

The Main Oil Gallery Plugs are on the ends of the Block.

 

There's two other plugs on the side of the Block that faces the front of the Mini, one is visible just down from the Oil Pressure Relief Valve. That one can be knocked in too far and it is a serious issue if it has been as it will cause the Oil Pressure Relief Valve to Hydraulic Lock in a Closed position and your Oil Pressure will go sky high, usually resulting in the Oil Filter exploding.

 

The other plug mentioned is also to do with the Oil Pressure relief vale, it is only accessible from the Sump Rail of the block (you need to split the block off the gearbox). That one can go in a long way (about 25 mm) without issue.

[Earwax]

I bought a block for a race motor with threaded end plugs/grub screws. I did the opposite of carbon and relieved the timing cover end plate and timing cover, after finding a weeping under pressure from the plug/grub screw on first rebuild.  After the first weep , i pulled the motor and it is possible two different thread profiles had been used on the hole. ( npt and ????) - my hydraulic specialist said the threadforms seem to be a perfect fit but they actually cross the threading pattern a little way down- causing a dint in the thread, which in a pressure feed system is enough to cause the weep.  ( i just re used the plugs that came out - whether they were correct or not ).  So after the disappointment of having to fully pull the motor to get to a weep , and not being sure that the sealant would fully work again - i made sure i could get at that plug in situ by just removing my alternator . ( not a perfect or ideal solution , but i now keep a close eye on that area, and it allows me to keep racing)

 

So the moral to the story - keep a close lookout on fit of galley grub screws. Good old press in plugs in road motors have never given me trouble.

Edited by Earwax, 01 January 2019 - 09:45 PM.