Now for the daft question... how does this work? I can't actually get the existing plug out. It's seized in tight. Have WD40'd it so see what happens. I'm presuming I turn the nut anti-clockwise? Not the t-bar? Once the new plug is in place, does the t-bar then need to be turned so it's as far away from nut as possible?
The item is called a Petcock.
The hex screws into the block with a right hand thread, install with PTFE tape. The Petcock in the picture is closed, the end that goes in the block has a tapered centre that seats in a taper in the outer threaded part. Play with it now before it is fitted to see how it works - hold the hex with a spanner and turn the T bar to open the Petcock.
You may have to get a blow torch to heat the old one and surrounding block to remove it, a note of caution, be careful, if you snap it off and leave part of it in the block it will ruin your day !
They don't usually leak. Determine where the leak is coming from, could be from the main ( larger) thread into the block, or more unlikely the valve itself.
You could try gently undoing the valve, then doing it back up again if it is the valve. They do not need doing up super tight.
K Seal is an additive that will seal leaks like that without clogging the radiator, you must shake and mix all the bottle contents before adding to the coolant. A much better solution than a broken off Petcock in a block.
That sound very plausible. Here's the back on mine when I removed it. When I opened it to drain the block, nothing came out so I assumed it was empty. When I removed all the bolts, I learned it was very full indeed! Yours may be in a similar state. I know that Wins and MGBD now stock reproduction side plates, which may be worth investigating. They're not to the original design however - they're just sheet steel with all the holes pre-drilled. Whatever torsional strength these plates added to the block (which probably isn't a lot), I imagine the repro ones don't add as much.I suspect that whats happened is that whatever grunge was in there was masking the pinhole as no leak was occurring prior to this.
On that side, no. You can do it in situ. But it involves supporting the engine from underneath and removing the crows foot mount. You can just about get to all the studs with a ring spanner, but it is tight behind the auxiliary drive housing. @BrianMac123 has recently successfully replaced a side plate with this method.Thanks redrover. Removing them side plates - is that an engine out job?
On that side, no. You can do it in situ. But it involves supporting the engine from underneath and removing the crows foot mount. You can just about get to all the studs with a ring spanner, but it is tight behind the auxiliary drive housing. @BrianMac123 has recently successfully replaced a side plate with this method.
I never considered that factor, but it makes complete sense. I assumed the pressing was to add a degree of torsional rigidity to the block, as it's quite thick gauge steel, and very very stiff. But aiding flow makes more sense on reflection.I was told it's shaped or sculptured to promote or encourage the coolant to flow around the cylinder walls more efficiently and not create eddies and dead spots.