prying and prodding intake/exhaust valve guides

[J_Walker]

just curious how the intake or the exhaust valve guides come out, yes the guides themselves.. apparently they do, some how. pulling on them with my fingers seems to do nothing, just trying to salvage anything/everything that's removable from this old broken GS head before it gets tossed into the aluminium scrap pile to be melted down into a firey death! 

[Old Mechanic]

Drive them out with a hammer and a stepped punch.

regards
mech

[Big Rich]

Mech, you may be able to confirm this: the valve guides are not to be used again after removed, correct? I think I read that in a service manual, but it doesn't really apply to Walkers situation ......

[J_Walker]

Mech, you may be able to confirm this: the valve guides are not to be used again after removed, correct? I think I read that in a service manual, but it doesn't really apply to Walkers situation ......

figured it was a good learning lesson, on something that I don't mind that if it gets messed up.. and if I ever [doubtful] have to do it in the future, I would know how to do it right.

plus, taking them out prevents some of the dross.

[Old Mechanic]

I recommended a hammer and a stepped punch since he is not trying to save anything. Valve guides should be checked and replaced if they have too large a bore diameter. With that in mind I would not reuse them. I think (ancient memory) that replacements maybe slightly oversized on the outside and undersized on the inside, so that when they are installed, they can be reamed for a precise fit with the valve stem, measured for runout with a dial indicator.

The guides may also be stepped which requires them to be driven out from a specific direction.

That ancient memory is from 1982 when I worked at a Mercedes Benz dealership, so long ago we used freon in an ashtray to chill the replacement guides before installation. R12  freon was 92 cents a can, 32 years ago. Obviously not an option today. We had MB factory tools to do the job.

regards
mech

[Big Rich]

You sir, are a wealth of information. Thank you.

[The Buddha]

Guides need to be removed after warming the head. You sit it in a 500 degree oven a few hours and quickly drive it out. Then put the head back in the oven, switch it off and let it cool slowly.
Guides are typically installed by putting in the freezer for a few hours with the head in the oven. Then you drive it in and sit it back in the oven and turn off the oven.
It can be driven out with a driver and brute force, but really I'd let the head ease up a bit with heat.
I do believe you can reuse it if it is in spec. I've seen people mark as it sits in the head, remove it, and cut it off so its not sticking into the port's air space and they reinstall it. Of course that is on a race bike. Which if it leaks - they dont care.

Cool.
Buddha.