This work took place over several weeks.
After getting the cylinder head and barrels back from bead blasting -
barrels:
head:
I then cleaned the vast amounts of bead remnants off with copious amounts of brake cleaner and compressed air. I had a lovely chat with a bike rebuilder extraordinaire mate and got the valves out (never removed valves before) & set them aside:
They were fairly coated in bead residue
and the valve stem oil seals were toast
but as I have a new set, I just binned the old ones. All valve sets went through the parts washer.
I decided this wasn't enough for head & barrels so after consulting the Slim Controller, one by one they went in the dishwasher
and dried in the oven - here they are just removed & cooling
. A spray with the air compressor to dry things out, then another, then an application of metalguard and into the airing cupboard they went for Xmas
.
The combustion chambers were very sooty
so I very carefully used a brass brush in my dremel to clean them up
. I was particularly careful to avoid the valve seats because the valves can't safely be lapped back in as per advice given here.
The valves were all a fair bit carbonised too
so I cleaned them up the best I could
.
Today I have been addressing the pistons. They weren't exactly clean - here they are pictured after a first, light, go over.
Right:
and left:
. I did one piston at a time to avoid mixing things up. First the rings got measured in case the gap between ring & top of gap was too much - but for both pistons it was well inside tolerance, I'm pleased to say. Then the rings came out and went in the parts washer for a taste of the old ultrasonics. Then the piston head & sides got a light going over with a scotch brite brush in my dremel. After that everything got another clean and the ring grooves got scrubbed with brake cleaner and an old toothbrush.
There's a horrid complex diagram in the manual about how the oil scraper ring gaps should line up, so I made my life easier with a picture
. I also measured the gudgeon pins to see if they were in tolerance & was pleased to find both were:
.
Last thing on the right piston was to refit the rings
and coat with metalguard before setting aside in a sealed bag for later use.
Then I repeated these actions on the other piston. They're both done and dusted now, ready for me to refit when the time is right. Before that happens I need a few warm enough days to coat the head and barrels in several coats of etch primer and several coats of silver paint. I hadn't planned to paint the engine but now the head & barrels have been blasted, they need protection.
