Spitfire Engine coolant drain tap

[MSZ]

Hi all,

My spitfire MK3 brass coolant drainage tap leaks from where it is screwed into the block. The tap itself is knackered, with lever snapped. Got a new one and so far have tried to fit, but it leaks every time ? I first used PTFE tape on the thread, then after that failed I used plumbers jointing compound, that failed to seal and then a fibre washer followed by a rubber washer………..still leaks coolant where  it meets the engine block. Do I need a copper washer or something else?

thanks Mike 

 

[NonMember]

I think it's a copper washer but it's a while since I changed one.

Check the thread is clean and of full depth - if it's obstructed by rusty crud at the bottom (which is highly likely) then the new tap won't screw far enough in to seal properly.

[MSZ]

26 minutes ago, NonMember said:

I think it's a copper washer but it's a while since I changed one.

Check the thread is clean and of full depth - if it's obstructed by rusty crud at the bottom (which is highly likely) then the new tap won't screw far enough in to seal properly.

So no additional sealant of any sort with the copper washer?

[Colin Lindsay]

Mine is fitted with a fibre washer but it's still a tight fit; as long as you're sure it's the correct version and screws right in to the end of the thread then some sealer won't do any harm at all.

[MSZ]

But what sealer to use in addition to the copper washer?

[NonMember]

You shouldn't need any sealant. If the thing bolts fully in until it compresses the washer, whether fibre or copper, and as long as the block face around the hole is flat and clean, then it will seal without any goo. If it doesn't tighten or if the face isn't flat, then no amount of goo will fix that.

If you insist on sealant anyway, then blue Hylomar is probably good.