Cylinder block coolant drain plug.

[mangocrazy]

As I was looking through the Haynes manual for guidance (always a dangerous thing, I know) I noticed a reference to the cylinder block drain plug. It's located in the centre of the block, at the back of the engine, below the core plugs. I established through trial and error that the hread pitch into which the plug screws is M10 x 1.0. Are these plugs generally available or is it simply a case of finding a suitable sized bolt to plug the hole?

[WestonE]

Hi Graham

Find a used one, wire brush it and get it plated. I think they are a tapered thread to promote the seal so not as simple as swapping in a bolt in a rare metric fine pitch!

Eric

[mangocrazy]

Cheers Eric, using a taper thread fits with what I observed, as there doesn't seem to be any flat surface that a crush washer could seat to. Plating and PTFE tape, I think.

It's also in a particularly inaccessible location when in the car. What fun...

[WestonE]

Hi Graham

I small amount of copper slip NO PTFE tape.

Eric

[mangocrazy]

Hi Eric,

Thanks for that word of warning. In that case I assume seizure is more of a problem than leakage...

Graham

[WestonE]

Hi Graham

Yes

[mangocrazy]

I believe I may have found an inexpensive component that would perform this particular job at least as well as the no longer available Fiat/Lancia part. It's from a UK company called Automotion Components and the part is a hexagon socket blanking plug with tapered thread. The part is available in a variety of materials; steel (self colour and zinc plated), stainless steel (A2 and A4) and brass. My preference would be for the A4 stainless (316 marine grade) due to its superior corrosion resistance propertirs.

These are available for the princely sum of 85 pence each in Metric fine (M10 x 1.0) thread pitch. There is a small order charge (£3.50) for orders under £30, but their product range is so large that I'm sure I can find other parts that I need (want) to make up the order to the required amount. This is a screenshot of the catalogue page for the part I'm referring to, and here is the link to their mechanical components catalogue:

https://www.automotioncomponents.co.uk/media/files/catalogue/Mechanical_Components_Handbook_2018.pdf