Hey guys,
I must be off my rocker. I'm not what you would describe as mechanically inclined. I don't really know my way around an engine, but now I've decided it's time to change that. I saw the motor rebuild for dummies thread and it gave me hope that I could do it too. I read through the entire thread, but unfortunately there was never a conclusion. Bummer. So I'm going to attempt this myself. I'm going to attempt to rebuild a CB750 engine with zero experience, and try to actually finish it. I hope others can learn from my experience and be inspired to try it for themselves.
I have a CB750 in running condition. It runs a little rough, and it leaks oil, probably because it has 66k kms on the engine without ever being rebuilt. My plan is to strip it first, inspect the internals, and rebuild.
So it began this past weekend. I started by removing the exhaust from the bike. Pretty straight forward. Unfortunately, one of the mufflers looks to be welded on to the exhaust manifold. I'll have to figure out a way to remove this.
I drained the oil from the bike, then removed the oil pan. That was a little messy. I left it over night to drain out with the catch pan underneath the bike.
Next day I tried attacking the phillips screws on the case covers. These were a real pain in the ass. I had at least 10 stripped. The screw extractor bit I had bought was not doing the trick. It turned out to only be useful removing screws that were stripped but already loose. I tried different methods at removing these, and the one I found that worked 100% was to cut a slot at the edge of a screw's head with a rotary tool. Then using a flathead screwdriver and a hammer, I hit the screw at an angle forcing it to turn. Some screws were set in, so cutting them was not an option. But simply finding the right angle and hammering at them eventually loosened them out. In hind sight, buying an impact driver may have saved me some headache. Also, I don't think drilling out stripped screws is ever necessary, but that's only my experience.
I disconnected all the electricals and lines to the motor, removed the carbs, and removed the frame mounts. Next was lifting out the engine. I had to get some help with this. The trick was to lift the rear of the engine first, then raise the front slightly to clear the exhaust studs. Then with a little wiggling the engine came out the right side of the bike.
I took the valve cover off, and I made an attempt at removing the valve train. I couldn't figure out how to remove the cam chain from its sprocket. I removed the chain tensioner, the bolts on the sprocket were stuck on hard. They would not come loose. I decided to call it a day here.
What a mess.
Note the broken valve cover gasket. It came out in 3 pieces.
