I have an 1987 325i coupe which i had on the road a few years ago,up until I realised the headgasket had gone! This was after replacing heater matrix and heater control valve which cost Ł150 for genuine BMW matrix! anyway since then it has sat in drive and now and again i fire it up and listen to the excellent exhaust note it gives through stainless system and tell myself i must do headgasket.
Well now the time has come and i'm going to do it!!! hooray!!!
I am after some advice on what to look out for when changing headgasket?
I am qualified mechanic and changing headgasket i dont have a problem with its the catch you out issues & usual cause of headgasket failure on 6cyl engine. ???
example= Head warp/twist how many thou tolerance is allowed across cylinder head face?
are they prone to corrosionat any particular point?
Do they crack cylinder head internally? and if so is it normally repairable? Is it worth having it pressure tested and repaired???
Any feedback would be much appreciated.
Oh almost forgot! I have heard the the headgaskets come in different thicknesses? Is this correct or was it just a rare case i heard about?
Also any advise on best place to purchase headgasket set with headbolts i would get from BMW normally but if there is a better option or same just cheaper i'm all ears. Any help,tips,pointers,etc would be grateful.
Stewart (Fridge & car mechanic in Essex)