This very short video shows a really old valve lapping tool - similar to the one I’ll lend you.
Note the oscillating “action” in the suction cup as it turns.
Vintage tools made of STEEL - far superior to those disposable tools made from the far east plastic trees today.
A lot of work has been happening away from DMS while I prep everything for final assembly. Beware a bit of a Mini photo dump. Too much to type so pictures will suffice for now
Before cleaning:
After cleaning with the vapor hone, some machining, then painting:
Lapped my valves the hard way (sorry @TLAR I completely forgot your offer 
):
Also blasted a bunch of other parts on the vapor hone and repainted then including my new-to-me RHD pedals from the UK and my old busted and rusty heater:
And finally began reassembling my gearbox after replacing all bearings and inspecting for wear:
This weekend at DMS I’ll be finishing my gearbox, reinstalling the crank, cam, and pistons in the block, reassembling the head, and prepping the transfer case by pressing some bearings.
Lots more fun to come yet. Doing the LHD to RHD swap at home soon in prep for getting the car trailered to DMS for motor install. Also finishing up the complete wiring loom replacement.
Did you by chance have the valve seats cut at all?
From that lone pic and seeing the pitting on the valve margin, the seats should most likely be cut.
No I didn’t get them cut. I’m scraping the barrel for funds to finish this rebuild so if it’s something that needs doing I’ll have to get by without it for now. Eventually I’d like to get new seats, valves, guides, springs, etc but I didn’t have the budget remaining. I’m hoping that a thorough lapping will keep me going for a good while so I can replenish funds to continue work.
I would strongly suggest you at least do a basic/crude leak test on the combustion chambers to test your valve to seat surfaces BEFORE putting the head on the engine.
This won’t cost you anything but time.
Something like this?
That seems easy enough to do at DMS
Yes!
A little time spent doing this simple test of how well the valve seal against the valve seats could mean the difference between being able to drive your car or not once you get the engine back together and installed.
On tonight’s agenda at DMS:
It’s going to be a good few hours of fun
Be careful during your pressing operations - make sure the bearings are going in straight. Do not rely on the pressing action to straighten out a crooked bearing - that often ends in an unsatisfactory result costing you more money and time.
Don’t be in a hurry.
Everything went into the transfer case perfectly. No extra pressure or bad angles. Next up is the gearbox mainshaft. It’s already been apart and rebuilt with new bearings, but tonight I have to remove it again… I got handsy and played with the shift control rod and accidentally caused the 3/4 synchro hub to slip past the detents
So now I’ll remove the mainshaft, reseat the detents, then install the mainshaft again. Wooo 
I almost forgot about that Arbor press! That is the way to go for absolute control!
That press is probably older than any DMS member at the Space!
Good choice for press opps!
Results from the leak test are as follows…
All valves that leaked did not leak quickly, no water ever entered the ports, and the air nozzle had to be on full blast with the tip inside the ports to even see any bubbles. There was enough air pressure coming out of the nozzle to blow some items off the table I was working on when not directing the air into the ports.
Cylinder 1: minor bubbles, very slow
Cylinder 2: intake leaked the most and could use another lap, exhaust slow
Cylinder 3: minor leak, very slow. Bubbles dissipated before picture could be taken
Cylinder 4: no leaks!
Dots were drawn with fine tip sharpie on the valves and seat edges to correspond with leak points. Chambers were dried, valves were disassembled and rotated, then rechecked for leaks. Good news is no consistency with either the valves or the seats, except maybe Intake #1. All leaks are somewhat random and likely just the result of high air pressure from having the nozzle inside the ports on full blast to even see any bubbles at all.
I am just an onlooker - and not a skilled one - but will the paint that looks like it will be inside the engine not cause issues after reassembly?
That’s the water jacket in the second photo and is the same as from factory, I see no issues with that. A little overspray in the spark plugs holes isn’t going anywhere either so shouldn’t interfere with anything except maybe provide a better seal to the new plugs.
Gotcha TIL
It’s worth noting that when they painted the original engines they just sprayed everything with minimal masking. There’s original yellow paint still in places that make me scratch my head.
Does anyone know if we have a cam timing disc? I’m at the point in my rebuild where I’ll be ready to insert the pistons and set the timing. I know we’ve got a piston ring compressor and a dial indicator.
Probably bringing the block, head, and gearbox in this weekend to do some final work on the motor and if one’s available, snag a storage pallet.
Cam timing disc sorted. Just need to get to DMS this weekend when I have use of the other car to assemble the block and set the timing, press the carrier bearings into my differential and check the preload, and get the valves back in the head. After that’s done I’ll be ready to assemble the engine and get myself a storage pallet 
Then it’s just a matter of getting the Mini to DMS in the next couple weeks to get the engine installed. I’M SO CLOSE I CAN’T WAIT TO DRIVE MY CAR AGAIN!
