Name that leaking engine part!

[Bacon Is Proof]

That cap roughly in the centre of pic (with another to the left) inset into the side of the engine (old Perkins diesel); what is it? It's doing a bloody good job of releasing all of my coolant into the sump.
On my OH's boat if it matters. I'm afraid I know nothing of diesel engines.

[SS2.]

It's a core plug.

[caziques]

Core plug

[Cocknose]

It looks like one of the core plugs. Like these;

https://www.ebay.co.uk/itm/VAUXHALL-2-0-BLOCK-CORE...

Edit; that was quick! comprehensively beaten to it!

[Bacon Is Proof]

Cheers, bet the missus dinner that PH would answer quicker than her boating forum.

[SS2.]

Bacon Is Proof said:

Cheers, bet the missus dinner that PH would answer quicker than her boating forum.

3 minutes - I feel we've let the side down

[cobra kid]

Could it be a core plug?

[shtu]

It's hard to tell from the photo, looks like it might be 1.25".

It also looks like the plugs themselves are in pretty decent nick, so make sure whoever replaces it cleans the rusty gunk out of the hole thoroughly and uses some Red Hermetite sealant when fitting the new one.

Edit - I see it's now called Hylotyte Red. Showing my age there.

Edited by shtu on Thursday 15th October 10:22

[Bacon Is Proof]

shtu said:

It's hard to tell from the photo, looks like it might be 1.25".

It also looks like the plugs themselves are in pretty decent nick, so make sure whoever replaces it cleans the rusty gunk out of the hole thoroughly and uses some Red Hermetite sealant when fitting the new one.

Edit - I see it's now called Hylotyte Red. Showing my age there.

Edited by shtu on Thursday 15th October 10:22

Cheers shtu.
It's leaking from a small hole and the temp started creeping up ten mins into our journey, so our next step is to try and bung it, fill her back up with water and nurse her back home. This will include turning the boat round on a stretch of river that is hopefully wide enough.

Next topic: Please help, I've beached my narrow boat.

[Scrump]

SS2. said:

Bacon Is Proof said:

Cheers, bet the missus dinner that PH would answer quicker than her boating forum.

3 minutes - I feel we've let the side down

2 minutes 58 seconds to be precise.

[tapkaJohnD]

Core plug. NOT a "freeze plug" as they call them in the US, in thr erroneous belief that they don't need antifreeze, 'cos these will pop out and prevent the block cracking.
John

[Dogwatch]

tapkaJohnD said:

Core plug. NOT a "freeze plug" as they call them in the US, in thr erroneous belief that they don't need antifreeze, 'cos these will pop out and prevent the block cracking.
John

The family had a pre-war Austin 7 in the Sixties and they had thermo-syphon cooling with absolutely nothing to stop the water circulating through the radiator. We unwisely left it facing North one Winter's night and in the morning the core plugs on the top of the block were sitting like mushroom heads on little pillars of ice. No problem though, wait for ice to thaw, hammer core plugs back in place, check water level and off!

So the Yanks may have a point.

[Megaflow]

Dogwatch said:

tapkaJohnD said:

Core plug. NOT a "freeze plug" as they call them in the US, in thr erroneous belief that they don't need antifreeze, 'cos these will pop out and prevent the block cracking.
John

The family had a pre-war Austin 7 in the Sixties and they had thermo-syphon cooling with absolutely nothing to stop the water circulating through the radiator. We unwisely left it facing North one Winter's night and in the morning the core plugs on the top of the block were sitting like mushroom heads on little pillars of ice. No problem though, wait for ice to thaw, hammer core plugs back in place, check water level and off!

So the Yanks may have a point.

They will do that. But, the only reason they are they is to support the sand core during the manufacture of the block casting, hence the name core plug. The sand core has a number of protrusions that go through the outside of the casting and secure the location of the core into the main mould, those then have to be closed off, that is done with core plugs. They are a necessary evil and if they could be done away with they would be. The freezing aspect is totally secondary and would never have been considered in the design off them.

[Boosted LS1]

Halfords sell a really good treatment that will seal that really well unless you decide to replace it. To remove it you bash it on one side so that it flips horizontal. Then you pull it out with a pair of pliers.

[paintman]

If they're all the same age you might want to consider having them all replaced.
At least that's easily accessible!

Does your system use a heat exchanger for cooling - so it's much the same as a car - or is it raw water cooled?
If the former use antifreeze in the system to reduce corrosion.