Welcome to the next part of the saga !
My goal for this weekend was to clean the spare engine along the major joints of the cam cover, head and barrels. I got side-tracked.
I've been trying for ages to find a way to get the cast alloy of Kawasaki engines clean. YouTube is full of videos of guys taking alloy engines and polishing them to a mirror finish.
But that's not what I want. The cast parts were never a mirror finish. More importantly, the videos almost always involved sanding or using abrasive compounds with a buffing wheel. Unless you immediately apply a heat-resistant lacquer, that kind of finish will oxidise very rapidly, but more importantly repeated cleaning like that will thin and weaken the engine casings.
Then I heard about a method which is far less destructive. It won't give me a mirror finish, but it will give me clean alloy that is closer to the original look.
All photos in this post by me
Above is the cylinder head viewed from above. I've done quite a bit of cleaning with Autosol, but it hasn't really given me the results I've been looking for. Also, don't worry about the actual cylinder head in any of these images; I'm intending to swap it out for one which hasn't got a damaged intake flange.
Part of the cam cover in it's "before" state. Lots of oxidation and dirt !
Step 1 in the process - a small amount of WD40 squirted on. Gotta love that fish oil !
Step 2 - lots of scrubbing with a kitchen scouring pad. I cut these into strips about an inch wide, which makes it easier to control and get into small spaces. Sorry for the blurry photo, it's hard to scrub with one hand and use the other to hold the phone and take a picture !
Step 3 - the final step is to wipe the filthy WD40 off with paper kitchen towel. This is how much dirt came off after just 5 minutes of scrubbing. Each small patch takes two or three cycles of WD40, scrubbing and wiping to come really clean. But bear in mind I'm taking off 45 years of accumulated dirt, grime and corrosion !
The end result after about 3 cycles of cleaning. While it isn't perfect, it is far, far better than it was. Some of the marks that remain are salt damage. They salt the roads in winter here in the UK as a way to stop them icing up, but it's terribly harmful to alloy (and steel, and paint, and plants and... well, everything it touches).
But now I've got the cam cover to this stage, it'll just be a case of periodically doing another cleaning cycle and watching it get better as time goes on. Once the engine is in the bike, it will be a case of being careful to wipe all the WD40 off after each clean. It's not super-inflammable, but it will burn if too much is present. But while the engine is in storage, it's ideal because a thin residue of ED40 will act as a good preservative and corrosion inhibitor.
On another part of the engine, here's the side view of the fins on the barrels before cleaning. They've always been perfectly horrible to clean !
This is the same part after one cleaning cycle - again, not perfect, but far better than before ! To help get into the recesses, I wrapped the strip of scouring pad around the back of a C-spanner, because it doesn't have any points or sharp edges that could scratch the alloy.
So instead of opening up the engine and taking the cam cover and head off (which was my original plan) I kind of got carried away and just kept squirting and cleaning until I ran out of scouring pads and my fingers started to hurt too much ! There's still a lot more to do, but the engine is starting to look significantly nicer than it did a couple of days ago !
For the avoidance of any doubt, yes, I did buy my own scouring pads. Stealing my wife's ones from the kitchen might not be too good for my health.....