M30 Valve spring compressors? (and other issues with my head.)

[DanH]

Anyone have a good valve spring compressing technique that they would care to share? what kind of tool works best for this?

I was thinking about doing my own valve job on my head since it is already apart and doesnt look too bad. (All the disassembly and testing was done at a machine shop.) It seems like the spring compressing will be the most difficult part of re-assembling the head.

What kind of compound would work best for grinding the valve edges?

I will still need to bring it into another machine shop to get the bottom resurfaced.

Thanks,

[Rory535i]

do you not have a valve spring compressor? as for the valves; go into an auto suppliers and ask for valve lapping paste.

[632 Regal]

you will have to tap the retainers to crack them loose then get a spring compressor. ummm grinding valve angles is completely different than lapping the valves. If your going to lapp the valves there is usually 2 kinds, use the grittier stuff first.

[Rory535i]

i lapped the valves on my head when i put a new cam in it and polished the base of them along with the combustion chamber. made the engine seem to run smoother and obviously gave the valves a great seal on the head. my spring compressor only just did the job, had to put a socket over the springs otherwise it wouldn't reach! take your time with the valves, it pays off in the end.

[DanH]

Sorry for slaughtering the terminology. (I've never done this before so thats why I'm asking.)

Also my valves have some carbon build up on them, is it better to scrape it off or soak them in some kind of solvent?

[Rory535i]

Sorry for slaughtering the terminology. (I've never done this before so thats why I'm asking.)

Also my valves have some carbon build up on them, is it better to scrape it off or soak them in some kind of solvent?

get a can of carb cleaner and with a bit of perseverance with a cloth you should be able to get it off. might need a few cans. that's what i did anyway but then i polished them aswell.

[winfred]

i buff the carbon off the valves on a bench grinder with a wire wheel, i use a regular c clamp type compressor to install the valve springs, mines a old blue point but any decent good sized unit should work. i remove the valve springs with a hammer and socket but that's best left to the pros

[DanH]

Thanks for the tip winfred... I just bought a wire wheel for my grinder recently. Wasn't sure if it would scratch the valves though.

Couple more questions:
The machine shop said my exhaust valve guide need replacing too... What is the spec for amount of play in the valve stems? I can feel them very slightly move side to side with both the exhaust and intake guides. Although, I dont have a gauge small enough to measure the movement.

Will new valve guide seals be enough to stop most oil flow?

Thanks,

[winfred]

they will probably be ok with just the new seals unless something weird happened and totally screwed the guides

[genphreak]

New guides are real cheap- like $5 each, so I would replace them as you probably will never do it again... are you going to grind the cam? If it takes the grind down so much you cano no longer get the valve adjustment right, there are little caps that can be fitted to the tops of the spring retainers which will make up for it... they are expensive as they are very rare- some smart bimmer shops have them- as well as titanium retainers and the like. I think they cost about the same as the guides... what fun you'll be having! GP