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Jim, I did a full rebuild on my TO-20 a few years back. Learned a TON about your very questions, and will answer best I can. 1. Definitely get a kit, don't buy parts and pieces, the kits are a better deal, you will save $$$, even if you don't use all the parts in the kit. I shopped around for rebuild kits a good bit, All the engine rebuild kits I found (including here) were Tisco kits. The kit was good quality, complete, no complaints whatever. Shop around! prices vary a lot! There are a dozen combination of rebuild kits. I recommend tearing the engine ALL the way down, decide exactly what you need, THEN get the best kit combination your needs. I didn't do that and spent a lot more $$$ as a result. I started with a plan to just replace rings/pistons/sleeves, and got a lower rebuild kit from the MF dealer (didn't have to pay shipping so it was cheaper than here). After I got into it, I decided to rebuilt the head, then decided to go with new valves. So, I bought a upper rebuild kit from here, then valves (here), then decided to replace crank bearing shells, water pump, and other parts most from here... Once I got started, I couldn't stop! 2. I cleaned my own block, After I stripped it down and pulled the sleeves, I cleaned with water, degreaser, drill & wire wheel brushes. Took a solid afternoon to clean it, but it was basically free. After spending big $$$ on rebuild parts, I was looking to save some $$$ where I could. Turned out quite nice. Easy enough to do yourself. Cam rides in the block. The clearences on mine was borderline, but tolerable. I have heard of guys that have their cams welded-up and turned down to meet tolerence, costs $$$, if you don't absolutely need it, don't worry about it. 3.I rebuilt my oil pump too. Tisco rebuild kit from here, again. The kit was good quality. It can be done without special tools, unless you decide to press and ream the new bronze bushings that come in the kit. I didn't feel I needed that so didn't do it. The difficulty is that the aluminum drive gear has to be pressed on the pump shaft, then drilled 1/2 in the aluminum, 1/2 in the steel shaft, tapped, and a set screw screwed-in to hold the gear in place. Getting the gear pressed on straight is important, drilling the steel/aluminum is almost impossible by hand...I tried. They do sell a special tool to help with all that, but it can be done without it, with patience. I was able to drive the gear on by clamping the pump in a vise, using a socket as a mandel and carefully tapping the gear on the shaft with a hammer. I used the neighbors drill press to drill the set screw hole after realizing I wasn't going to be able to do a good job by hand. Tapped the hole with a regular hand tap. The rebuild kit includes new relief valve spring, plunger, etc. which you will want also. 4. I stripped my head, took to a machine shop to check for cracks, warp, polish-up the seats, and press in my new valve guides. If you take the head to a shop, don't waste a bunch of time cleaning the head first. I did, they cleaned it anyway, and did a much better job than me. Cost me 70$ to do all that, they painted it too. When I got the head back, it looked like brand new. I was thrilled! Jim, don't know where your at in the Buckeye state, the machine shop I used was the NAPA machine shop in Mt. Vernon, OH. They have a lot of experience working on AG engines, and really did a fine job for me. Since I used new valves, etc. the head rebuild was EASY. The only special tool you need is a valve spring compressor, I rented one for free from the local AutoZone store. I don't know what a shop charges to do the whole head rebuild, it might be a wash to do as I did, use new valves, and rebuild the head yourself. 5. Sounds like your crank is fine. Take a good look at your bearing shells. Mine were pitted real bad, I replaced them, that was another ~$90. Bearing shells are not part of a rebuild kit. Also, DO the plastigauge check on your crank clearences as specified in the manual. It takes time, but plastigauge is the TRUE measure of your crank tolerences as it factors in both crank and bearing wear. If the plastiguage looks good, just put'er back together with your existing parts as is. I plastigauged my crank and old shells, then again with the new shells. I gained ~.001 - .002" or so in tighter clearance, and was right in tolerence by just replacing the bearing shells and doing nothing with the crank. Hope that helps. I found in my case I had a couple cracks in my block. Very discouraging, I finally got over my initial sense of "all hope is lost", and figured out a way to fix it. I work at an adhesive manufacturer that makes industrial/commercial adhesives. Epoxies, urathanes, and Methacrylate based adhesives, with applications in the commercial fields that would shock you where metal parts are glued, rather than welded, and stonger because of it. Cast iron is a great example where the right adhesive can be better than welding/brazing. Anyway, after consulting the technical guys, I decided to patch my block with a couple different kinds of epoxies. I JUST finished my website. Here is my story!
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