Thread: 300tdi block coolant drain plug - sealant and washer

Flushed the cooling system and renewed the coolant on my 300tdi Defender yesterday.

The drain plug in the block was tight ... but I managed to get it eventually without damage. Not realising it was anything special at the time, I replaced the washer with a new regular flat copper washer, not a AFU1882L as per pic.

I also didn't use any sealant ... I now see the genuine replacement part has some red goop on it.

The location of the plug also means it's very difficult to get any feel for the torque being applied also.

It doesn't appear to be leaking ... but I also don't want to risk it coming undone.

Do I need to remove and re-fit? If so, is it the correct washer, or the sealant or both that is really needed?

What type of sealant would be appropriate if re-using the original plug?

Does anyone know the thread? If I have to remove and refit, I'd prefer not to drop all the coolant - so would like to screw in a temp plug if I can identify something of the correct size.


AFU1882L.PNGERC9410.jpg

I use Permatex liquid thread sealant on things like that. This one (you can buy a 6mL tube as well).

Permatex(R) High Temperature Thread Sealant, 50 ML – Permatex

The workshop manual says:

Drain plug, cylinder block 25Nm

I assume that's the drain plug to which you refer.