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Are there any tips before I go ahead and install rings / pistons?

The ridge is removed and I honed the cylinders last year. Following the hone I scrubbed and washed the cylinders thoroughly with water and detergent.

As I understand it, the oil control ring "spirals" on, and the compression rings go on with a spreader (top up). There should be .015 to .003 ring clearance and .005 to .015 ring gap. I imagine the rings & cylinders get a liberal coat of assembly lube.

The pistons drop in with a sleeve type compressor, and the rod caps get tightened to 40 to 50 ft-lbs. The cylinder numbers on the rods face the cam.

That should be it, right?

Worst cylinder
Worst crank pin
Typical rod bearing
Piston
NOS rings

it will help with plastic tubing on the rod bolts.to help guide the rod onto thr crank,and to protect the crank from damage

I don't know how old your piston rings are but if you have any rust on the oil rails I would buy new ones. Rings generally come with detailed instructions and the top ring is usually different from the second ring.

Sounds about right. Alter the ring gabs by 1/3 so they don't line up with one another. I dip the piston and rings in a bucket of oil before installing. Its messy but I like to be sure I have lubed everything well. How long before start up? Use white motor grease if its going to be a while. Motor oil will all run off before starting.

Joe

Stove,
In order to give what I see pictured a good chance of working well all the rust is going to be gone, right?
The hone marks are way too rough.The smoothest you can make the resurfaced walls is none too smooth.400-500 Hones and 400 grit wet or dry paper are better at smoothing the walls than rings and the rings WILL be short lived if they have to do the job.
What is ring clearance? The maximum ring SIDE clearance in the grooves is .006 and less is better.
End gap should be .003 PER INCH OF BORE MINIMUM when measured in the smallest part of the bore.
Good luck and work hard on that rust.

Absolutely NO assembly lube on the skirts and rings.

I am PUMPED! The first piston went in no problem.

Bob, thanks for letting me know that the cylinders need to be finished better. You saved me from near disaster! As it turns out I had them honed to about 220 grit, so I went back and finished the cylinder to about 600 grit. And I cleaned up some more rust as per your instructions.

The ring side clearance meets specs, it measured about .004 or .005. The minimum end gap is beat by a long shot, it was about .030 instead of .015. There was about .010 between the piston and the cylinder at the top, and closer to .005 at the bottom of travel.

Thanks everyone for your kind assistance.

The little oil hole on the side of the rod points toward the cam.And the notch on top of the piston should point to the front of the motor if everything is assembled correctly.
And, as mentioned above,ring end gap is measured at the bottom of the cylinder. The cylinders usually taper by abt. 4thousandths.
Good Luck...............

Would someone please tell me the correct way to install the rod caps / dippers? I realize the dipper faces the cam, but is the hole in the rod cap towards the back of the dipper or is it centered?

Hole towards back

Hole centered

I would guess the hole goes towards the back, but if so I think the previous owner had these in wrong! If I have to reverse things, is it more important to keep the bearing cap mated, or is it better to flip the piston?

I suppose on this particular engine it won't matter much, but I'd still like to do my best to do things correctly.

The cap position must be maintained no matter what.

Stove, right now there are some FREE (no cost) 216 engines listed on the VCCA online forum. It's possible those don't have the rust issues you are dealing with.

Go for it Stove!

Thanks Frank! I'm really excited, the engine is beginning to look complete. I can almost hear it running. Here's an update:

My pistons are in! Installing the pistons was really fun, like a big improvement was being made with new rings, versus just cleaning stuff. Also it was a new experience for me using the ring spreader / compressor. I dipped the rings in oil just like Joe.

4 of the 6 rod caps were previously installed with the oil hole towards the middle of the dipper. I had to turn 4 of the 6 pistons 180 degrees to get the oil hole towards the back. It was necessary to flip the pistons to maintain mated bearings.

One of the rod caps looks like it doesn't even match the rod! I suspect these have been in and out at least twice, because the rods / caps are marked with any combination of dots, dashes and numbers.

3 of the 6 rod caps are torqued nicely to 45 ft lbs. I have 3 more caps to install. 2 of the clearances measured between .0015 and .002. The third was closer to .003! I'm not too thrilled about the generous clearance.

Bearing three looks pretty bad. The others looked OK to me. Pics:

Piston 1 installed

Bearing 3 has seen better days

Piston 3 face

I assume you're assembling the rods without shims and still getting wide clearances? Since this is a patch-up job on an engine on its last gasp, how about doing some careful filing on the rod cap to reduce the clearance a little on the wide one? That was an accepted practice 50 years ago when trying to nurse a few more miles out of a tired old engine, and it will still work today. That bearing with the Babbit metal flaking out of it will probably last as long as the rest of the engine, as long as it's not abused, over-revved, etc. On a full rebuild, I wouldn't even consider re-using it, but that's not where this job is going, obviously.
Jerry

Thanks Jerry for the good tip on the bearings.

I took about .001 off each of the caps, but it didn't seem to make a measurable difference. How much do you think can be safely removed? I wasn't too sure so I stopped at about a .001 and put it back together.

As long as there's still some Babbit left, you can keep filing. A strand of hair measures about .0015"-.002", so it's not like you're making a huge change in size, or making the big end of the rod oval by much. The hammering effect of a loosely-fitted rod top-to-bottom is what makes rods fail, not a little bit of out of round at the parting line between the rod and the cap. On reconditioned rods with plenty of Babbit, I like to use Prussian Blue and scrape the bearing to a perfect fit with the crankshaft, then add shims to get the clearance right, but yours are beyond much benefit to doing that procedure. Too bad we're not closer together- - - -I've got a couple of good-condition 216's, and I'd be happy to work with you as a mentor on a full overhaul. If I don't pass some of the tricks of the trade along, they're just going to go away when some of us oldtimers kick the bucket!
Jerry

Jerry, that would be awesome to work with you! The next best thing is the internet I suppose.

OK, the rod caps are all buckled up. I'm feeling pretty good about the rod bearings now, I worked a little harder to get the sloppy bearing tightened up.

Would you believe the previous owner had every piston in backwards? At least he was consistent. The rod caps were slapped on with no rhyme or reason.

I double checked everything, now it's all oriented correctly. Next up: oil pump.

Bottom End

Stove,
I think you'll be surprised with how well it will run... Those 216's are hard to kill. Good luck with it.