A few questions on overhauling cylinder heads. I bought these off of Ebay so I don’t know their working condition.

1. How do you remove valve stem seals? (And is the insertion just a reversal)
2. How do you recognise if a valve is in need of replacement?
3. Likewise with valve stem guides?
4. I’ve taken on board the ‘sticky’ re. inserts for lubrication bolts. (Thanks, no doubt I’ll have questions when I get that far) Would it be recommended to do the s/plug holes? These seem perfectly OK. Just wondering if the aluminum deteriorates over time. I’ve always been aware not too overtighten.
5. Is it acceptable to clean the inner surface of the cylinder head with fine wire wool? It appears to only have a sooty deposit but I haven’t investigated further.
Finally
6.How do you recognise if the push rod tubes are damaged to the extent that they will allow oil leaks?

Just to explain I want to do as mush possible on rebuilding the engine. I don’t want to be stripping things down in the future if I can avoid it. Age/finance/space won’t permit!
Thanks in anticipation of replies.

1 pull them off with pliers - you need a nice snug tubular drift to put them back on - the cheapy white ones are easy to split so care must be taken you also have to work out which is which and fit them the right way round and protect the collet grooves from ripping them when they go over the valves

2 it wobbles in its guide the stem is polished, the seat is concave or pitted the edge of the valve has cracks

3 see no 1 above

4 the aluminium wont deteriorate over time but ham fisted work in the past may be waiting to bite you on the arse

5 yes

6 they have holes in them or the open ends are all out of shape and bell ended.

Sean, many thanks for your clear, consise response.

if it were the pair on ebay they looked low milage and in good order - but check the threads.

Sean, Not sure if they are the same pair you refer to. I did get them from Ebay, though about 8 months ago.

What size helicoils am I looking for to insert into the head oil line holes? I know they are M7s but I understand there is a thread pitch size to look for (would there be a length requirement as well?)
Also, do the oil cooler tubes bolt directly into the crankcase without any washers or seals? Some time ago that I took it off. Pretty certain there isn't, can't see how anything would fit.

Final question (for tonight anyway). Can the front and rear crankshaft oil seals be removed without a special tool? i.e drill two holes and insert self tappers and persuade out?
Thanks again in anticipation of replies.

1 n"o" then
2 m7x1 1.5dia length - but they may not need helicoiling just dont torque them as in haynes half will do but with experience you sort of feel th ecopper bite and thats it.
3 should have copper washers either 2 round ones as in factory or a folded over spectacles type more common in gasket sets.

4 and final......yes

"you scored 4 with no passes"

Not sure if I misread the above. The oilcooler need 2 rubbers seals going in to the engine block

yup your reading it better than me !

actual oil cooler pipes rather than the head oil feed pipe, gets 2 rubber sleeves on the pipe theyt compress and seal when the m16 pipe nuts are tightened down

so that should have been "in that round you scored 3 points ....." in your best Magnus Magnusson voice.

Many thanks Sean and 2CViking.That lot will keep me going for a while!

Haynes and Autobooks say to use high melting point grease when installing the front and rear crankcase oil seals. Is this essential? (i.e. high melting point, got general purpose LM).