I've not done any head work other than cut seats, surface and change exhaust studs, but I've done a lot of bottom end work - rods bearings, pinion races and bushing, truing, honing, etc. With valve guides, general advice is "take them to a machine shop" but I've been to two dealerships plus 4 auto machine shops and only 1 even acted like they would attempt to R&R the guides. Said they'd air hammer them out and couldn't ream anything under .312 ??? The valves are only .310/.3095 and I have an air hammer so thanked them for their time and came home...

I'm sure there's some guys on here who know so my question is - doing it by hand (air hammer, oven etc.) would you go out toward the top and back in from the top, or out thru bottom and back in thru the top? Or just say screw it and buy the $600. set of press adapters and do it like the book shows? Only need to do intakes in 2 sets of heads (mine). And yes, I know I'll also need a ream and hone at least. I have Neway cutters for the seats.

Part the reason I'm asking is the exhaust guides have less than half protrusion into the port as the intakes. Looks like it's be better to go out from the bottom for exhaust and the intake guide protrusion is about equal so it's going to have about the same distance to travel either direction... I'm totally open to any (educated) opinions. Thanks

 

you want to clean off all the carbon (kinda goes without saying) and press them out from the port & out the spring side.to install,we heat the head to 320* ,use a .001 or .002 over size guide from whatever size guide is presently in the heads now and press them in the spring side using a press fit lubricant.let cool & hone guides to size (im not a big fan of reamers but they can be had from GOODSON is any size you want) then just cut seats and your done.i made i simple fixture to hold the head in my press for removing & installing guides

 

What had me bluffed the worst, "the book" shows the fancy press tools but reads as if they are pushed out downward - same direction as installed. Makes more sense to push out from the bottom and back in from the top. Looks like it'd be really easy to press out from the bottom with just a deep socket against the spring seat boss. And if I had access to a lathe, it'd not be too hard to make a seat rest for a press. So yeah, I'll press rather than hammer. I feel a lot better about that method.

I'll get my guides (going back cast iron) a .311 reamer, ball hone and press lube from Goodson.

Thank you for the tips Kirby and I sincerely appreciate your input. Stay cool down there if you can.

 

yep, pressing is a better way to go, especially with aluminum heads.
on the ole ironheads, i would heat the head to 450*f and the guides would practically fall out, and a lot of the times, it didn't even need over-sizes guides. on install heat the head and freeze the guide.
need an arbor to press out the guide, easy to use a bolt and nut in a pinch.

 

As mentioned by Kirby, clean all carbon from the guides in the combustion chamber before removing them or it will gouge the aluminum (guide hole in head) when removing them or you will have trouble getting the new guides in straight. And the gouges will be a path for oil to enter the combustion chamber from the rocker boxes, which is bad. Heat the heads when installing new guides, but I always put the new guides in the freezer for about 20 minutes before installing them. And I always used a little Hylomar on the new guides, just in case. Also, sholderless guides must be installed to a specific heigth (the part of the guide that sticks out at the top). The HD tool does that automatically, but you can press them in slowly and measure to get it right.

I always mic the guide that comes out to be sure I'm using the correct size guide as well. Oversized guides should be marked with rings at the top indicating oversize. But not all are, so check that to be sure the new guides are the correct size.

Paul