QUOTE(tornik550 @ Sep 17 2010, 07:40 PM)
I had to take out my engine to fix a few issues. I took off the heads to inspect a few things. I figure that since I have the heads off, I should see if anything needs replaced. I really don't know the history of the heads. I purchased them from somebody on the internet. I figure the story that I got from the PO was pretty much worthless. Here are my questions-
1. I removed the springs and valve keepers. How do I safely remove the valves from the guides? The end where the keepers connect to the valve seems to get hung up on the valve guide.
2. How can I tell if my valve seats are worn?
3. Approximately, how much am I looking at spending to replace the valve guides?
4. If there are cracks, are they typically visible to the naked eye?
5. Are there any other major issues that I need to look at when inspecting the heads? I am replacing the entire valve train so I am looking more for non-valve train related issues.
Almost forgot- I am working with a tight budget (another kid on the way).
What type of engine is this?
1. you may be experiencing some spread at the keeper area. I use a very small air tool that looks like a belt sander, but with a fine polishing belt to knock those edges down when this happens. If you are planning on replacing the valve you can do something similar with fine sand paper or a file. If you are unable to remove the valve through the guide your guide may not be too worn, but you would have to have the proper tools to check the wear. "feel" is ok when you are familiar with what a new or worn guide feels like.
2. The more the seats are worn the more recessed into the head they become. You can assess the seats by having a shop inspect them and attempt to freshen the valve job. A quick visual would be possible if you put magic marker on the sealing surface of the valve and with a bit of force engage it against the valve seat. You could then see the size and location of the seat interface with the valve. If its more than a few millimeters and at the outside edge of the valve it may be time to refresh the valve job, and find out if the seats need replacing.
*If these are the factory seats you might want to have them replaced full stop.
3. If you replace the guides you need to valve job the head. If you do that you may want to have the seats done as well, and install new valves like most people want to do. If the seats are original then replace them, so you're looking at a full rebuild which is about 600-700 without crack repairs. Of course you would have to find someone you trust to do it.. which is the kicker in the cylinder head game.
4. Cracks are visible when you bead blast the head and heat them in the oven for a bit. Some are under the exhaust seat and may not be visible until the seats are out. Look into the exhaust port from both sides, and carefully at the spark plug holes. Also inspect the exhaust stud bosses as these get cracked all the time.
5. rocker assemblies should be checked for wear. If you are upgrading the valvetrain alot of folks are using the upgraded single spring/cro mo retainer setup from jake. Inspect the tips of your adjusters for wear and pitting.
have fun!