Thread: Cylinder block plugs on 1955 S1

was it this model engine that had a welsh plug that was interchangeable with bung off 44gal drum? I vaugely remember being told something but unsure--sorry! someone will know!


Oh and rules say PICS.. LOTS OF PICS!!

Originally Posted by dobbo321

Hello all
First post so bear with me

i have just purchased a 55 S1 86" ute cab. I am replacing the upper cylinder block welsh plugs, one was badly leaking. These are the 2 x plugs (look similar thread to 3/4 BSP) that screw into the block. They are located on the passenger side of the block. One in front off and one to the rear of the exhaust manifold. Both are inline with the 4 exhaust posts and slightly covered by the exhaust manifold when it is in place. I have fitted plenty of normal tap-in brass welsh plugs but am having trouble sourcing these screw in types of the right external flat shape so they don't fould the exh mani when it is refitted. Any help on suppliers or alternative ways of making them would be appreciated.
Cheers
Dobbo321
Baldivis WA

Just bought a tap for them at the Nambour swap last weekend.
1' by 16 tpi British Conduit they tell me. Bloke in gympie sells the Aluminium plugs but they are easy enough to make in the lathe. Cut a slot for a screwdriver, screw them in with some "Stag" and grind them off flush when tight.
Getting the tap to clean the holes is the hard part. I had been looking for months.

I cleaned the female thread with a thread file and bought the plugs from Dunsfold Land Rover,

Cheers Charlie

They are called Core Plugs and there should be more than two of them. Check at the rear of the head you should find another one (well at least on the 2.25 engine there are) They should be a conduit thread. Brian Hjelm can supply the tread tap for them. Ph 07-33997033
There should be 1 @ 1 3/8th " which goes into the rear of the head & 4 @ 1" which fit into the top of the head.
Then there are three that go into the side, not sure of the sizes Rover part numbers 09191; 512412 & 527269. The first two are smaller than the last one.

You can purchase them from British Off Road at Nambour Ph07-54451094, Gary CLR on Ebay, The Old Landie shop in SA, Four Wheel Drives in Melb. plenty of people sell them. Best to do the lot and the welsh plugs whilst you can.

Originally Posted by RobHay

Brian Hjelm can supply the tread tap for them. Ph 07-33997033
There should be 1 @ 1 3/8th " which goes into the rear of the head & 4 @ 1" which fit into the top of the head.

No, I can't. I don't stock British Standard Conduit. Lack of demand. BSCon is a well and truly obsolete thread.

Damien White, 07-3807-0798, has a swag of new BSCon tools.

Whitworth will work, if you're in a pinch.

Originally Posted by d@rk51d3

Whitworth will work, if you're in a pinch.

BSCon may be Whitworth 55 degree thread form, but 1" BSW is only 8 tpi. 1 3/8" BSW is 6 tpi.

As a stop gap measure, you can use ordinary cup type welch plugs .. 1" from memory ..... it works . On my 107 years ago, I tapped the holes to 3/4" BSP and bought some plugs for the hardware store , used some teflon tape and it worked fine .

For the pedants out there: I have a lathe so can turn up some plugs in whatever thread . Just need time to perfect my thread cutting skills 4 wheel drives did sell them , made from aluminum , at a exhorbitant price .

MIKE