DIY Blast Gun

I ordered some rubber trim and special "glass locking" trim from McMaster Carr for the blast cabinet. If you've never ordered from McMaster Carr, you should check out their web site. The best industrial supply web site hands down.

While waiting for the trim,  I took a closer look at a cheap blast gun I bought. Its kind of clunky.

My blast cabinet is a little small so maybe I can make something better with this little blow gun.

Below is a 1/8" pipe tee fitting, a 1/8" pipe/tube adapter and the tip from the small blow gun.

Fit them all together and we've got a nice little blasting gun.

DIY Soda Blaster

Now that the engine is completely apart, I started thinking about how to clean it. At first I though that I would have to scrub and scrub with a solvent until she shined up. In the mean time, I also was learning about soda blasting. Soda blasting is probably the safest way to blast because its almost completely harmless to the engine. It doesn't remove metal and it dissolves in water so clean up is a breeze. Not only that, you can Do It Yourself.

Sounds like a plan!

The two large holes will be where my arms go. The smaller one on the side will be where my shop vac hose goes. It will simply suck out all the left over soda, dirt & dust. The plastic bin maybe a little smaller then the ideal, but I should be able to fit all the engine parts in there.



Now I'm making holes for the air hose and the media blasting hose.

I love grommets. These two fittings are snug as can be in there. The barbed fitting is for the blast media and the larger fitting is a quick connect fitting for the air hose. Doing it this way with the pass thru fittings will make this really portable and convenient to use. "Plug and play", if you will.

Air hose inside the blast "cabinet".

Blast media hose in side the blast cabinet.

Hole cut on top for the window. I need to get some nice rubber edging for these larger openings. This is gonna look really nice when its done!

DIY Valve Compressor

I tried my 4lb dead hammer to knock the valve keepers lose. Didn't work at all. Is it just me or are these kz750 valve springs really really strong? I'd whack it with the dead hammer and the spring wouldn't compress at all.

So I followed what many do to make a valve spring compressor- cut a notch in a socket and use a c-clamp.

In use. At the center, you can see one valve keeper in place. The other fell off and is sitting behind the valve stem.

I knew it would be a tight squeeze. This was the longest socket I had to spare so the notch isn't very big. Just like playing the game "Operation" as a kid. "It takes a steady hand!"

But I got them all out, and everything looks okay to me. I know later on the valves will need special attention.

Spit Across the Middle

Time to get the crank case split. But let's not get ahead of ourselves here. There 23 bolts holding it together yet.

23 bolts later, I was able to crack it open at a pry point. I was worried that this would be hard to split, but these two pieces used a liquid gasket so it was pretty easy.

I'm not in the clear yet. That damn stuck piston is a thorn in my side. The upper case was blocked because the pin was sticking out. So on goes the DIY pin puller, but now I'm packing some heat this time around.

It worked. I got the pin out just enough to remove the piston. Here's a picture of the piston with the pin still partially in it. What's the brown scarring?

Gears!

Pan Down

I'm still mostly following the shop manual (if I get stuck on something I skip ahead), and next up is the oil pan. I'm excited about this one because the inner guts of the engine will finally get exposed (from underneath anyway).

The 17 bolts came off easy, but the pan was stuck. I tapped with a hammer and prodded with a screw driver, but it wasn't going to come off that easy. The ever resourceful forums suggested (among other things) a 4 pound "dead blow hammer". This is essentially a heavy duty rubber mallet as I found out later when I purchased one. I'm trying to be a bit more careful and get the right tool when I can.

After several strong swings and whacks all around the oil pan, she just suddenly flopped straight down. 

It wasn't too bad in there. The oil was thick and black. There were also some small bits of metal and whatnot in there. I know its not a good sign to have a lot of metal bits in the oil pan, but isn't it normal to have at least some? This may have been the first time the pan came off too so maybe its just from breaking the engine in.

You can see them below. They look much bigger covered in oil than they really are after washing them off. Not all of them are metal. Some of it is just grime falling from above through the cylinders.

And cleaned up a bit. Man, I can't wait to get the rest of the engine squeaky clean! I'm getting tired of grime everywhere.

The oil pump.

Here's a shot of what's under the breather cover. I believe both the out gassing vent and the intake breather are both in here. Some bikes have them located at different spots on the engine.

Getting really close to splitting the rest of the case wide open and pulling out the gears and stuff. I can't wait!

Piston Pin Problems

A few weeks back, the left piston slipped right out with a few taps of a hammer. Not so for its sister, (or should I say evil twin). The right one didn't budge. I smacked it good with a hammer a few times. Nothing. And yes I have the circlips out.

So now I've made a piston puller and tried that. Yes! The pin is sliding out (with lots of torque applied).

But after an inch or so, she didn't want to cooperate anymore. I really cranked on the puller and she just won't move. Is this normal?

And once again, I chipped off some aluminum. This stuff is more brittle than a rose dipped in liquid nitrogen. The large socket dug into the piston just above the pin as seen in the picture above. At that point, I didn't really care. I just wanted the piston pin out. I can always get a new piston.

So now what?

I know some mechanics and bike enthusiasts out there are cringing. I look at at this as a learning experience. I'm not afraid to make mistakes, just as long as I learn from them. Besides, even if I turn this into a parts bike, I'll consider it the best small engine repair course that $300 can buy.

I'm going to make a running list of all the stuff I break (for fun and for motivation to be more careful).

1. Chipped piece off engine case (cosmetic)
2. Chipped piece off clutch hub (may need replacement)
3. Chipped piece off right piston (will need replacement)
4. ?

Two Steps Forward, One Step Back

OK, ready to get back to work with my new tools in hand.

I used the chain wrench to hold the flywheel and was able to get the nut off. I did scratch the fly wheel a tiny bit with the chain wrench. Next time I'll put a rag or something under it.

The Harbor Freight bolt puller set worked perfect to get the fly wheel off. The two pieces I used are in the picture below. Snap the pointed tip on the bolt puller thing, screw the bolt into the fly wheel and off it came. Finally some things are working in my favor!

Here's the bolt puller in action. Fly wheel popped right off with no effort. I read a lot of people have problems with these too.

And the fly wheel off. The sprocket is for the starter motor chain. I plan on deleting the starter and go kick start only. Can I delete the starter clutch and this sprocket too? I'll cross that bridge later.

Stater motor off.

Now finally back to the engine sprocket. I tried to dremel the stuck nut awhile ago but stopped that foolishness. I got the old chain back out and wrapped it all over the sprocket to jam it up. I used the impact wrench at first, but it didn't work. Maybe I wasn't patient enough. I never used one before and it was just spinning and making a loud "clack, clack, clack" noise. Next came out the cheater pipe. I bounced my full weight on it and the nut at last came loose.

Sh*t. The way I had the chain jammed in there put too much pressure on the aluminum case and a small piece broke off. Fortunately it shouldn't effect anything.

On the other side, I got the clutch plate off.

What's not shown is my first lame attempt to get the clutch hub off. This spins freely and it needs to be held in place. So I took just 3 of the bolts used to hold the clutch plate on and screwed them into the hub. Then I wrapped the chain wrench around the 3 bolts and went to work on the nut. Big mistake. The 3 little bolts didn't handle the torque very well and one snapped out chipping off a small piece of aluminum from the hub in the process. I may need to buy another one.

I left it at that for a few days and went back to it after my head was clear. I was going to fashion a clutch holder tool with some steel, but then I thought I could just jam the flat steel strips in there. I know, sounds like a reckless move on my part again. I made sure everything was snug and secure, and it was. I then used the impact wrench on it. Nothing at first- just that loud "clanking" sound. Kept at it a few seconds more and the nut came off with no damage to anything else. Success!

New Toys

Next up after building the engine stand was getting some better tools for the job. I went to Harbor Freight to buy some cheap China stuff with the names like "Pittsburgh" and "Chicago" branded on them. WTF? Are they really trying to fool people? I'm a bit disappointed at myself for buying China (and for our screwed up corporate cronyist economy in general), but I can't afford a $250 impact wrench. I got all the stuff below for under $90. I'm a hypocrite, I know. At least I'm aware of it so that's got to be worth something.

Feelers I know I'll need eventually.

Chain clamp for keeping moving parts from moving.

Bolt puller set. Not sure exactly how this will work, but I'm hoping it will pull out that stuck piston pin.

 Electric impact wrench for stuck nuts & bolts.

Some impact sockets.

An impact screwdriver. I used this last night to get 3 screws off the right engine cover. Worked great.

Off the Ground

Clearly I need an engine stand of some sort. I've gotten as far as I could without one. I took some measurments of the engine and drew up a design in Sketchup.

Its got 2x4's and casters for the base. Angle iron and 3/8" threaded rods for supports. I don't have many power tools so most of this was done the old fashion way as you'll see.

Making 2x4 cuts with my little table saw (one of the few power tools I've got).

Using deck mate screws. I love these things. They zip right in there and hold tight.

This would make for a nice furniture roller, wouldn't it?

Hand sawing angle iron. I tried the dremmel but that was too slow. I thought about getting a power saw or an angle grinder, but for a small job like this I figured it wasn't really worth it.

This is a regular hand drill, not a drill press. I was worried about this part. I had some drill bits but had no clue if they would bite into metal. It actually worked ok. I used the old engine oil for lubrication too. I'm gald I didn't dump it yet.

Assembly...

Finished product. Looks a lot like the sketchup model. Nice.

And mounted. I'll still have to sit on a stool to work on parts of the motor, but its 100x times better than having it (and my butt) sit on the floor.

Yeah, the angle iron drilling and cutting sucked. I love the end result though. It turned out almost better than expected.