Top end rattle!

[Bungle george]

My cars been sat for about 18 months, I have recently got it back on the road but on idle it has developed a nasty top end rattle?! I have changed the oil and filter but made no difference...if I raise the revs to 1400rpm it goes away..any ideas or solutions?

 

[Dan519]

sounds like the dephaser has got clagged up with old oil while it's been standing. if you get it hot a few times, and change the oil again fairly soon it might clean itself out if you're lucky

 

[Bungle george]

Oh right fingers crossed then... What's the dephaser? And where is it located?