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I can't directly answer your question simply because I only go to Colorado once a year to skii & SB. :) But, what I can suggest to you comes from a good deal of experience: do as much of the work as you can. What this basically boils down to is you aren't going to spend $3K or so on a valve grinding tool and valve seat stones so you let the shop do that part of the heads for you. Disassemble the heads:
Check cam journal caps for markings. If not marked, label them so you know which one goes where. You do not want to get two mixed up as they are precision machined for the position they are in. Misplacement of the cap will lead to cam binding and abnormal wear.
Remove cams
Remove lifters and put in a small bucket (1 qt) with engine oil to submerse them in. This will keep air from entering the lifter and causing it to tick.
Remove valve springs, caps, keepers, and base washers. Put the springs in a box, put the rest of the small valve parts in a ziplock baggie.
LEAVE THE VALVES IN.
LEAVE THE VALVE SEALS IN. Then take it to the shop and have them chem-dip the heads, pressure test the head, clean up the valve seats and valve faces. Ask them NOT to lap the valves in. When you get them back, you should check the head for any damage the shop may have caused in the process of their work. Inspect the head's mating surface to the block. There should be no dings in the metal. Be especially observant of the area where the head gasket's metal sealing rings touch. Inspect the head for warpage too. As this point you are ready to do your work. Remove the valves (which should just be sitting in the valve guide) and the valve stem seals. Dont install the new seals yet. This would be a good time to port the heads or to do anything that will be machining metal from the head. Do not concern yourself with the placement of which valve went where. They are all ground at the same angle, the lapping process mates the valve specifically to the seat - you will be doing that part yourself. Get yourself a tube of valve lapping compound and a valve lapping tool. Be sure to hand lap every valve very well. This ensures a really good seal between the valve and the valve seat. Be sure to thoroughly clean up any residual lapping compound. Be sure to label where each valve goes. Once you have lapped all of the valves and cleaned everything, install the new valve stem seals. You can use a 10mm 12 point socket on a long extension to place the seals on the stems and drive them onto the stem using a small hammer. *note* You left the old seals in there when you took it to the machinist because you didn't want the valves to fall out. The seals hold the valves in place even though there is no spring/cap/keepers.. Tell them NOT to remove the valve stem seals in their cleaning process. Also, you didn't install the new valve stem seals before lapping the valves because they offer a good deal of resistance on the valve stem and it makes for difficult valve lapping. At this point you are ready to install the spring base washers (washer to keep the spring from riding directly on the surface of the aluminum), springs, caps and keepers. There is a very nice tool for installing the valve cap keepers and it runs about $50.. This process is how I rebuild my engines now. I can no longer trust people that take my money and screwup things like valve stem seals or drop my parts and damage them. Doing the heads this way will allow you to inspect their work. You aren't giving them much to do so the opportunity for them to fuck them up is smaller than if you took a completely assembled head to them and asked them to rebuild it. Never do that. Take the care and precautions yourself. You can only trust that you will not be careless with your parts. The cylinder block is another trick part as you probably dont have the $50K laying around for a boring/honing machine. Once again you will be depending on the local greasebuckets to handle this for you. If your block is in good shape or you dont need to overbore for larger pistons, I would suggest rigid honing the cylinders and leaving it at that. A few cans of carb spray and compressed air will clean the block off/out very well. Port out your coolant passages and wash her down with some soapy water and a brush. Apply paint. If you are concerned with the condition of the block or need to have it punched out for bigger bobbers, you need to ask the machine shop what their boring (snicker) process is. Let them explain to you how they do it. What you are wanting to know is if they align bore the block to the centerline of the crankshaft journal or to the oil pan deck. Many many shops bore to the oil pan deck which is NOT the correct way to align a block for a rebore. You must align-bore the block to the crankshaft centerline to ensure the cylinders are in fact, perpendicular to the crankshaft. If they aren't, the chances of breaking connecting rods is high as the piston will deflect the conrods from the crankshaft. You could ask them what reference they use for boring, the oil pan deck or the main journal centerline. Have the cylinders finish honed for cast piston rings. Have the freeze plugs replaced! If would be a good idea to have them measure the deck height and deck the block and plane the deck if necessary. I found one stock block that had no deck warpage (well, 0.0005" - five ten-thousandths), however, there was 0.003" variation between the deck height on the front and deck height on the rear. You are allowed to machine 0.008" (eight thousandths) from the deck so we planed the deck by 0.003" on one side an 0.00 on the other to bring the deck back to levelness with respect to the crank's centerline. Have the crank inspected. You may need to have it reground or just micropolished. Whichever they do, be sure to have them measure the spec of each journal (to the tenthousandth: 0.000x") and write it on the crank. You will need this info to determine which bearing grade you should use. You'll need a piston ring install tool and a ring compressor to install the piston into the cylinder, both are inexpensive tools you can pickup from autozone or any automotive store. Torque spec for the rod endcap nuts is 28-32 ft/lbs. Some of the service manuals out there say 43-48 ft/lbs, of which the bolts will shear off at about 40ft/lbs. It is a typo. Just remember 28-32 ftlbs for the conrods. Be sure to orient the piston rings according to the SM too. At this point you are ready to put it all back together! Of course, use assembly lube on all journals/bearings.
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[ agpowers@bellsouth.net ] [ Zemulator Information Sheet ] When pigs dance, you better get it on video... "You never really learn to swear until you learn to drive."
-George Carlin
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08:49:55 12/05/02
