Drain tap leaks (engine tap)

[Durango2k]

Hi,

After putting water in my engine and fixing the thermostat housing, I now found a few leaks around the drain taps. The radiator tap seems to be less critical, but what would you do if the engine tap would drip, drip, drip.... ?

I mooved the lever, no more dripping- but I am not sure wether it was also the base of the tap it came from. I had to use several fibre washers, else the tap would face 70 degrees upwards, so I steepled them until it sat vertical after tightening it down.

Carsten

[mgcjag]

Hi Carsten...have a look here...how to refurb tne tap viewtopic.php?f=3&t=9595

[abowie]

I never fit them. I worry that if they fail they can drain the coolant and wreck the engine. I just use plugs.

[Moeregaard]

I'm with Andrew. I bin the taps and fit plugs. It's one less thing to worry about on long road trips--and it's also two fewer opportunities to open the garage in the morning and find a green puddle.

[Durango2k]

Ok, I may give up on mine.

Which thread size ... ?

Carsten

[abowie]

Again don't quote me but 1/4" NPT. Tapered. I use brass ones from the plumbing shop.

[Moeregaard]

The drain taps use a fiber washer as a face seal, so they'll be 1/4" BSP (British straight pipe), which has one extra thread over its U.S. counterpart. We see a lot of this on our side of the pond, where the American tapered thread will go into a hole tapped for its British counterpart, but it's not really the way to do things(!).

[Durango2k]

I now duely bought a plug, 5.98 pounds shipped to my house.

Tried to fit it, darn. Thread to short and too far back. Could not put it in engine.

Somehow closed hole with plug and made it loosely to stay there, then went to bench and dismantled the tap. Found that inside is no seal, just some 2 brass parts rubbing on each other. Found that they were not lapped in the factory. Rough. This is why it is not water tight.

Used valve grinding component, and turned the "cock" inside the tap opening until it was all smooth inside. Cleaned it and it was tight (mouth tested). Added Hylomar paste, assembled, fully repaired.

Now, had some vendor written a note that you have to lap the parts to match them perfectly so that the tap becomes water-tight, I could have done that before mounting it to the engine.

Now I lost about 8 ltrs of water and coolant in total and had not a nice time removing and fitting it again and again.

Carsten

P.S.- no, this is not a rant about british car parts quality....not really

[abowie]

This is why I use the brass tapered ones I suggested.