poohbear Posted November 21, 2009 Share Posted November 21, 2009 Hi all, just had my head resurfaced following a head gasket failure and have been cleaning up all the carbon deposits around inlet and exhaust ports. Have noticed that some of the valve seats are nice and shiny and that others or more of a copper colour - It looks like the top layer/coating has come off! Is this something to worry about or do I just re-grind the valves and forget? Why do I get the feeling I'm going to be going back to my friendly head specialist. Dave Quote Link to comment Share on other sites More sharing options...
western Posted November 21, 2009 Share Posted November 21, 2009 see how they look after lapping the valves in, if the change to a grey colour all round then the seats should be fine. Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 22, 2009 Author Share Posted November 22, 2009 Thanks Western - have had a go at grinding in the valves. Guess I'll see if it works or not in due course! Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted November 22, 2009 Share Posted November 22, 2009 They almost look like they have a spot of surface rust, as Western says a bit of lapping will probably save them. Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 23, 2009 Author Share Posted November 23, 2009 Thanks Bowie69 - Like I mentioned - when I removed the head they were all lovely and shiny, almost like a chromed finish. Had a mild panick attack after cleaning all the carbon off as they had changed to a motolled grey/copper colour. having spent an age with the grinding stick they now have a nice grey colour, although it's not 100% uniform over the whole seat face. they are the original valves in the original ports and so I'm hoping all will be fine. Will see if they seal alright once it's all back together! Dave. Quote Link to comment Share on other sites More sharing options...
TD5 power Posted November 23, 2009 Share Posted November 23, 2009 hi as long as there is a constant grey line around the valve seat and the valve itself then thats fine, you can actually grind valves too far then it takes longer for them to open but for a LR diesel i shouldn't have thought it too critical. matt Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 23, 2009 Author Share Posted November 23, 2009 hhhmmm.... may be popping the valves out and having another go - I was a bit concerned that I was grinding the seats away having spent most of Saturday at it, but I think it is probably better to keep going and get a real good seal than risk it. As you say - the 200Tdi is hardly a 'performance' engine. I can't understand why the seats became so pitted (or appeared to be anyway), they are the original valves so must have been pretty well seated before. I'm starting to think that I should have left well enough alone and just replaced the head gasket without trying to refurb the head - if it ain't broke, don't fix it - comes to mind. Dave. Quote Link to comment Share on other sites More sharing options...
TD5 power Posted November 24, 2009 Share Posted November 24, 2009 hi i would of thought if you spent a fair time doing them they should be ok, as nothing has been changed still original valves and the seats haven't been re cut. But if you hadn't refurbed the head you wouldn't have had the fun of grinding valves and spending hours cleaning bits At least you know its now good for another few thousand miles. matt Quote Link to comment Share on other sites More sharing options...
petethepilot Posted November 24, 2009 Share Posted November 24, 2009 Hi all, just had my head resurfaced following a head gasket failure and have been cleaning up all the carbon deposits around inlet and exhaust ports. Have noticed that some of the valve seats are nice and shiny and that others or more of a copper colour - It looks like the top layer/coating has come off! Is this something to worry about or do I just re-grind the valves and forget? Why do I get the feeling I'm going to be going back to my friendly head specialist. Dave Sorry my but I couldn´t stay in my chair imagining you going to see your "friendly head specialist". I think it´s not that serious yet, it´s only carbon deposit... I must be very tired... Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 24, 2009 Author Share Posted November 24, 2009 According to SWMBO - anyone who spends more time with a 20 year old lump of metal than those dearest and nearest needs a 'head specialist' Quote Link to comment Share on other sites More sharing options...
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