silent running

This might be a really stupid question, but how are the valve guides lubricated? Other moving parts of the engine with close clearances are directly oiled but as far as I can see, the valve guides/stems are not???

Any oil or grease that I use in assembling the stems into the guides, is going to be capped off by the stem seals, whose whole job is to stop oil getting down there. So what's to stop the stems running 'dry' in the guides? Or are they supposed to? Should I use grease in assembly or not? Does it not really matter, because the stem only moves a short distance corresponding to the valve lift?

dazdavies

iTrader: (22)

I've always coated the valves with engine oil before dropping them into the guides.

I've never had to do anything more than that and have never had problems.

silent running

How about the stem seals? A dab of grease to fit them on or just engine oil the same as the stems/guides?

chrisUK300

iTrader: (10)

The service manual states

"Apply engine oil to oil seal before press fit"

PM me your email addy and ill send you the relevant section if you want it

Chris

silent running

Cheers all, yes that's what I'd read in my PDF manual, I was wondering whether there was any secret knowledge that anyone knew that would improve on Subaru's standard method. But if it's by the book, then so be it. Thanks for the advice!

chrisUK300

iTrader: (10)

Good luck with it mate

dazdavies

iTrader: (22)

If you've got the manual then do everything as the manual suggests. I've done it like that and every engine I've built hasn't let go (yet).

Why differ from something thats been proven by the manufacturers and is there in black and white.

Ows

how did you install the stem seals?did you just giv em a good push on by hand or do they need an extra tap in with something?

frayz

iTrader: (7)

I always push stem seals on by hand and fit them dry. I fit them dry as this aids them gripping to the guides. I then add a light oiling of the stems before droping the valves in.

silent running

LOL just so I've got a better chance of engine failure really - what do Subaru know anyway? LOL

No, actually it's because the only comprehensive PDF manual I've got is for a 2002, so there are a few variations from what I've got which is a v2 CDB with v4 heads. Best to check!

ZEN Performance

The valve is very hard material, running in a softer guide, and the lubrication comes in the form a tiny amount of oil wiped onto the valve by the stem seal with every opening.

silent running

I was wondering if it was something like that Paul - the actual part that needs lubricating is only very small, close to the seal.

frayz

iTrader: (7)

Bronze guides are aided by the self lubricating material too.

silent running

Yes I thought bronze had some sort of weird property like that. Well it's sorted now, I put the seals on dry and then dipped the stems in oil and inserted them. No problems.