The V8 Owners Forum -

Hi all,
Having issues replacing core plugs on my disco 3.9 serp.
I have removed the downpipes, 1 manifold, the starter and both engine mounts and have the car on a ramp, I purchased new genuine LR core plugs and put them in using a hammer and a socket that fits just insider them, I hit them into just past flush and used a little copper gasket sealant on the edges, I also made sure the block faces were clean before installing them, after filling with plain old water to test, 3 out of 6 were weeping, this was with no pressure in the coolant system!
Has anyone got any tips to get them to seal properly? this is driving me nuts!
Cheers,
Olly

The normal way - after making sure the seat is clean and undamaged - is to use the ball of a ball pein hammer in the centre to spread them out. All you need to do is produce a visible dent to tighten them adequately.

Thanks Dave, I did wonder about this but thought as they were dished inwards (concave?) it may have actually loosened them, I have read a few topics on here suggesting chemical metal etc. but think that might be a bit extreme?!

olly_richman wrote:Thanks Dave, I did wonder about this but thought as they were dished inwards (concave?) it may have actually loosened them, I have read a few topics on here suggesting chemical metal etc. but think that might be a bit extreme?!

Dished inwards? Not come across those.

Neither way is the way I install them and never had one leak.

1. Remove old and ensure that the core seat is clean.
2. Smear some hylomar blue on the core seat
3. Line up core plug and using an alloy drift that is larger than the core drive it home flush.
4. Shout to wife to put kettle on.

Anything used on the inside will remove the seal tension

Ok cheers lads,
I have a set of alloy bearing race drifts, I'll use one of those, just to confirm then- Flush will be fine, they don't have to be below?
Thanks for the help,
Olly