Anyone know what would cause a top end rattle?

I thought it was the chain at first but the noise is definitely from a tappet and from the top end!

Also had a loss of water for weeks, changed radiator, water pump and turns out the head gasket is gone. As water is still dropping and the HC went through the roof when tested from the expansion bottle.

So I know it needs a head gasket but I'm baffled to why it's started rattling like crazy. Only does it when it's warm and mainly on idle. Give it a big rev and it'll go, but then come back eventually on idle.

If you've got coolant mixing with your engine oil, it's going to make the oil runnier, I think, so oil pressure will drop. The mixture is also bound to be less effective as a lubricant, so wear rates will be horrendous.

I don't think it's leaking into the oil as there is no milky like gunk on the dip stick. And the water loss is very minimal.

I'm started to think maybe the tappets need setting again at the top. The rattle is intermittent.

The tappets are not meant to be adjusted as they're hydraulically adjusted automatically. There is a procedure for setting them described in the Haynes manual. If you set them as per 1.3 Favorit/Felicia there's the problem.

Edited 22 March, 201313 yr by anewman

Problem solved. For now!

I checked on auto data for how to set the tappets...which was wrong!

They said to take the slack out of each tappet, obviously in the correct procedure. And then once there's no slack tighten the tappet 2 more turns. Well, I didnt realise at first, but this opened the valve to which I had no compression. So I just took the slack out of each tappet and locked them. The car runs alot better now and I don't need to change down to 2nd to get up hills anymore!

The loud tapping went the night before when I put some engine flush in the oil and drove it that night and in the morning....bit of dirt in one of the hydraulics maybe?